CHSE0900 Module 6: Biological Hazards

What Occupations are at risk for encountering Anthrax?

1) Animal handlers 2) Those handling animal carcasses, skins, hides, or hair

What Occupations are at risk for encountering Brucellosis (undulant fever)?

1) Cattle or pig handlers 2) Those who handle the carcasses and meat in slaughterhouses

What are the 4 general forms of Bacteria?

1) Cocci 2) Bacilli 3) Spirochetes 4) Actinomycetes

What Occupations are at risk for encountering Orf (virus in sheep)?

1) Slaughterhouse workers 2) Farmers 3) Shepherds 4) Sheep shearers 5) Butchers 6) Those who cook sheep

What Occupations are at risk for encountering Tularemia?

1) Small rodent handlers 2) Rabbit hunters

Why would an inspection for Air Quality need to be conducted?

2) Inspections to assess the suitability of a building space for a particular group of workers and type of activity. 3) Inspections to identify the possible causes of complaints from building occupants.

What are Fungi?

About 70,000 species have been identified. Fungi may be unicellular or multicellular, and range in size from the visible mushrooms to microscopic species.

What are Actinomycetes?

Actinomycetes - branched filaments.

How do Amoebae cause Humidifier Fever?

Aerosolized Naegleria antigens have been associated with cases of humidifier fever in office and industrial workers.

How can Airborn exposure to Bacteria cause toxicity?

Airborne - Bacteria cause infectious diseases by entering the respiratory system. Common airborne infectious diseases include legionnaires' disease, other pneumoconiosis, and tuberculosis.

What are Antimicrobial Agents?

Antimicrobial agents prevent growth. They are incorporated into or applied onto materials or products to slow or stop bacterial and fungal growth. Usually they are incorporated into products during manufacturing.

What disease do Arenaviruses cause? Where are symptoms produced?

Arenaviruses produces Encephalomyelitis and Viral Meningitis. Symptom site: Central Nervous System.

How do Arthropods (e.g. mites), Birds and Mammals generate reservoirs of Bioaerosols?

Arthropods (e.g. mites), birds and mammals can produce effluents that become airborne and form a component of some aerosols. The organisms can act as reservoirs, amplifiers, and disseminators.

What diseases can Arthropods cause?

Arthropods, such as chiggers and mites, can cause dermatosis and sometimes act as carriers for other parasites.

What disease does Aspergillus flavus cause? What are the sources?

Aspergillus flavus causes Cancer. Human exposure results from inhaled Toxins (aflatoxin) from agricultural products.

How does Temperature affect Fungal growth?

Aspergillus fumigatus is considered a thermotolerant fungus because it grows well over a wide temperature range (i.e., 18°C to 45°C).

For personnel who work in Central Supply in Hospitals, what hazards are present?

Cleaning surgical instruments poses the greatest potential hazard in Central supply. Direct injection of microorganisms is possible if the skin is punctured with dirty instruments.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Filters?

Dirty filters that are subject to moisture provide a good growth medium for microorganisms.

What is Farmer's Lung?

Farmer's lung disease is a form of HP that has been linked to exposure to high concentrations of thermophilic actinomycetes (warm-loving gram positive bacteria). HP outbreaks have also been associated with bacteria used in the manufacture of detergents.

What diseases can Helminths cause?

Helminths are responsible for schistosomiasis, creeping eruption, and hookworm.

How do Human Sources generate Bacteria?

Human-source bacteria are generated when people talk, cough, and sneeze. Droplets from the respiratory tract and mouth may contain bacteria as well as viruses. The larger droplets can only travel a short distance before they fall out of the air.

How does Temperature affect Fungal growth?

Light may influence sporulation, but not growth. Fungi can grow well in light and complete darkness. Dark spored fungi is very resistant to ultraviolet radiation.

How are Biological Hazards transmitted?

Like chemical contaminants, biohazardous materials can be transmitted to a person by: 1) inhalation 2) ingestion 3) injection 4) physical contact Bacterial, viral, rickettsial, fungal and parasitic infections may result from exposure to infectious biological agents.

What types of Amoebae have been implicated in Building Related Illness?

Naegleria and Acanthamoeba are amoebae that have been implicated in building related illness.

What are Spirochetes?

Spirochetes - spiral rods.

What is the First Line of Defense against Microorganisms?

The mucous membranes contain secretions that inhibit bacterial growth, and the secretions flow toward the outside of the body, by way of the mucociliary escalator.

Historically, what types of Biohazards have Laboratory personnel encountered?

The occupational risk of hepatitis B and shigellosis was also greater for laboratory workers.

Fungi Table

The table below lists infectious and hypersensitivity diseases that may be caused by exposure to fungi, and sources of the fungi:

How can Semi-porous Materials be used to control Microbial Growth?

Wood studs and furniture are semi-porous. The procedure listed above may be followed, if contamination is superficial.

New York City Fungi Remediation Table

* Susceptible groups include infants less than 12 months old, persons recovering from recent surgery, immune suppressed people or people with chronic inflammatory lung disease (e.g. asthma, severe allergies, HP).

What are features of (bacterial) Endotoxins as a Bioaerosol?

1) Airborne Unit: Cell fragments 2) Health Effects: Fever, chills 3) Sources: Stagnant water reservoirs

What are features of fungal allergens, glucans, and toxins as Bioaerosols?

1) Airborne Unit: Cell fragments 2) Health Effects: Headaches, mucous membrane irritation 3) Sources: Damp surfaces

What are features of (protozoa) Acanthamoeba (allergens) as Bioaerosols?

1) Airborne Unit: Cell fragments 2) Health Effects: Hypersensitivity pneumonitis (HP) 3) Sources: Contaminated water reservoirs

What are features of (bacterial) Allergens as a Bioaerosol?

1) Airborne Unit: Cell products 2) Health Effects: Asthma 3) Sources: Industrial processes

What are features of (fungal) Volatile Organic Compounds (Microbial Volatile Organic Compounds-MVOCs) as Bioaerosols?

1) Airborne Unit: Cell products 2) Health Effects: Headaches, mucous membrane irritation 3) Sources: Damp surfaces

What are features of (mammals) dogs, rodents, and cats as Bioaerosols?

1) Airborne Unit: Dried skin scales, urine, saliva 2) Health Effects: Asthma, rhinitis 3) Sources: Animals, animal bedding

What are features of (birds) Pigeon allergens as Bioaerosols?

1) Airborne Unit: Dried skin scales, urine, saliva 2) Health Effects: Hypersensitivity pneumonitis (HP), asthma, rhinitis 3) Sources: Animals, nests, droppings

What are features of (arthropods) Dermatophagoides (allergens) as Bioaerosols?

1) Airborne Unit: Fecal pellets, body parts 2) Health Effects: Asthma, rhinitis 3) Sources: Settled dust, house dust (dust mites)

What are features of (protozoa) Naegleria fowleri as Bioaerosols?

1) Airborne Unit: Organisms 2) Health Effects: CNS infection 3) Sources: Contaminated water reservoirs

What are features of (fungal) Sporobolomyces (allergens) as a Bioaerosol?

1) Airborne Unit: Organisms 2) Health Effects: Hypersensitivity pneumonitis (HP) 3) Sources: Damp environmental surfaces

What are features of (bacterial) Legionella pneumophila as a Bioaerosol?

1) Airborne Unit: Organisms 2) Health Effects: Pneumonia, inhalation fever 3) Sources: Cooling towers

What are features of (bacterial) Mycobacterium tuberculosis as a Bioaerosol?

1) Airborne Unit: Organisms 2) Health Effects: Respiratory infection 3) Sources: Human hosts

What are features of Influenza Virus as a Bioaerosol?

1) Airborne Unit: Organisms 2) Health Effects: Respiratory infection 3) Sources: Human hosts

What are features of (algae) Chlorococcus (allergens) as Bioaerosols?

1) Airborne Unit: Organisms, cell fragments 2) Health Effects: Asthma, rhinitis 3) Sources: Outdoor air

What are features of (vascular plants) Ambrosia (ragweed) (allergens) as Bioaerosols?

1) Airborne Unit: Pollen 2) Health Effects: Asthma, rhinitis 3) Sources: Outdoor air

What are features of (fungal) Alternaria (allergens) as a Bioaerosol?

1) Airborne Unit: Spores 2) Health Effects: Asthma, rhinitis 3) Sources: Outdoor air, damp surfaces

What are features of (bacterial) Thermoactinomyces (allergen) as a Bioaerosol?

1) Airborne Unit: Spores 2) Health Effects: Hypersensitivity pneumonitis (HP) 3) Sources: Hot water systems; hot, damp surfaces

What are features of (fungal) Aspergillus toxins: aflatoxin, ochratoxin, sterigmatocystin as Bioaerosols?

1) Airborne Unit: Spores 2) Health Effects: Liver cancer 3) Sources: Damp surfaces supporting fungi growth

What are features of (fungal) Histoplasma capsulatum as a Bioaerosol?

1) Airborne Unit: Spores 2) Health Effects: Systemic infection 3) Sources: Bird droppings

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Cooling Coils?

1) Avoid using porous materials like acoustic lining in areas of the HVAC system that are subject to moisture. 2) Design and operate the cooling coils so that there is minimum carry over of moisture.

When assessing the Outdoor Air Intakes of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Bioaerosol sources near the intake. For example: plant debris, feathers and bird droppings, insect or rodent infestations, sanitary air vents (i.e. from washrooms), cooling towers, evaporative condensers, standing water. 2) Below grade outdoor air intakes, where water and debris tend to collect.

What Occupations are at risk for encountering Weil's Disease (bacillus in rats)?

1) Coal miners 2) Bargemen 3) Sewer workers 4) Research workers

When assessing Outdoor Air, what should be considered in terms of sources that could affect Air Quality?

1) Crop planting and harvesting - exposed soil, soil turning, disturbance of plant material. 2) Excavation or construction operations. 3) Wastewater treatment or irrigation. 4) Textile mill. 5) Slaughterhouses or rendering plants. 6) Composting operations.

When assessing Fan-coil and Induction Units in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Dirty heating or cooling coils or filters. 2) Excessive water in condensate pans. 3) Inadequate drainage from condensate pans. 4) Moisture and surface microbial growth in or near units.

When assessing Heat Exchangers of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Dirty heating or cooling coils. 2) Excessive water in condensate trays. 3) Inadequate drainage from condensate trays. 4) Blow-through of water droplets onto surfaces downstream from the coils. 5) Dampness and microbial growth on acoustical linings.

When assessing for Water Damage in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Evidence or history of plumbing or roof leaks, water infiltration or spills, high humidity (>70%), or musty or moldy odours. 2) Discoloured carpet, window coverings, or materials, and signs of attempts to clean or disinfect them.

When assessing Return Air Plenums of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Excessive surface deposits. 2) Dampness and surface microbial growth.

When assessing Supply Air Plenums and Ductwork of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Excessive surface deposits. 2) Dampness and surface microbial growth.

What is an example of a Level 4 Fungi (Mould) Remediation?

1) Extensive contamination (> 100 contiguous sq. ft.) 2) Examples: Multiple wallboard panels.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled?

1) Filters 2) Cooling coils 3) Drain pans 4) Humidifiers

What Occupations are at risk for encountering Erysipeloid?

1) Fishermen 2) Fish handlers 3) Sealers 4) Whalers

What is an example of a Level 5A Fungi (Mould) Remediation?

1) HVAC systems (< 10 sq. ft.)

What is an example of a Level 5B Fungi (Mould) Remediation?

1) HVAC systems (> 10 sq. ft.)

What Occupations are at risk for encountering Tetanus?

1) Handling jute (spores in soil mixed with jute) 2) Anyone in contact with horse fecal material

When assessing for Chronic Condensation in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Inadequate insulation, or infiltration of humid outdoor air that causes chronic condensation on windows, perimeter walls, or other cool surfaces.

When assessing Window Air Conditioners and Evaporative Air Coolers in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Inconvenient location for maintenance. 2) Dirty grilles. 3) Standing water in condensate pans or sumps. 4) Moisture and surface microbial growth in or near units.

How can Condensation in Hot, Humid Environments be controlled?

1) Insulation 2) Air barriers and vapour barriers 3) Pressure

What Occupations are at risk for encountering Louping-III?

1) Laboratory workers 2) Shepherds 3) Farmers 4) Veterinary officers 5) Slaughterhouse workers (sheep)

What is an example of a Level 3 Fungi (Mould) Remediation?

1) Large isolated areas (30-100 sq. ft.) 2) Examples: Several wallboard panels.

When assessing Potted Plants in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Microbial growth on leaves, soil, plant containers, or surfaces in contact with the containers. 2) Excess moisture due to over watering. 3) Discoloured carpet below the containers.

What is an example of a Level 2 Fungi (Mould) Remediation?

1) Mid-sized isolated areas (10-30 sq. ft.) 2) Examples: Individual wallboard panels.

What Occupations are at risk for encountering Hookworm?

1) Miners 2) Agricultural laborers 3) Tunnel workers 4) Farmers

What is required for Level 5B Fungi (Mould) Remediation?

1) Minimum requirements for remediation overseers: Qualified building staff. 2) Respiratory protection: Full-face respirators with HEPA cartridges. 3) Gloves: Yes 4) Eye protection: Yes 5) Protective clothing: Yes 6) Remediation while unoccupied: Yes 7) Vacation of adjacent areas: Advised if occupied by susceptible groups* 8) Containment required: Critical barriers, airlocks, decontamination room within critical barriers. 9) HEPA filtered negative air: Yes 10) Dust suppression: Misting 11) Bag contaminated materials: Yes 12) Post remediation cleaning of work area and egress: HEPA vacuum & clean with damp cloth &/or mop with a detergent solution. 13) Clearance testing: Yes

What is required for Level 4 Fungi (Mould) Remediation?

1) Minimum requirements for remediation overseers: Qualified health and safety professional. 2) Respiratory protection: Full-face respirators with HEPA cartridges. 3) Gloves: Yes 4) Eye protection: Yes 5) Protective clothing: Yes 6) Remediation while unoccupied: Yes 7) Vacation of adjacent areas: Advised if occupied by susceptible groups* 8) Containment required: Critical barriers, airlocks, decontamination room within critical barriers. 9) HEPA filtered negative air: Yes 10) Dust suppression: Misting 11) Bag contaminated materials: Yes 12) Post remediation cleaning of work area and egress: HEPA vacuum & clean with damp cloth &/or mop with a detergent solution. 13) Clearance testing: Yes

What is required for Level 3 Fungi (Mould) Remediation?

1) Minimum requirements for remediation overseers: Qualified health and safety professional. 2) Respiratory protection: N95 disposable respirator. 3) Gloves: Yes 4) Eye protection: Yes 5) Protective clothing: No 6) Remediation while unoccupied: Yes 7) Vacation of adjacent areas: Yes 8) Containment required: Critical barriers 9) HEPA filtered negative air: No 10) Dust suppression: Misting 11) Bag contaminated materials: Yes 12) Post remediation cleaning of work area and egress: HEPA vacuum & clean with damp cloth &/or mop with a detergent solution. 13) Clearance testing: No

What is required for Level 2 Fungi (Mould) Remediation?

1) Minimum requirements for remediation overseers: Trained building staff. 2) Respiratory protection: N95 disposable respirator. 3) Gloves: Yes 4) Eye protection: Yes 5) Protective clothing: No 6) Remediation while unoccupied: Yes 7) Vacation of adjacent areas: Advised if occupied by susceptible groups* 8) Containment required: Critical barriers 9) HEPA filtered negative air: No 10) Dust suppression: Misting 11) Bag contaminated materials: Yes 12) Post remediation cleaning of work area and egress: HEPA vacuum & clean with damp cloth &/or mop with a detergent solution. 13) Clearance testing: No

What is required for Level 5A Fungi (Mould) Remediation?

1) Minimum requirements for remediation overseers: Trained building staff. 2) Respiratory protection: N95 disposable respirator. 3) Gloves: Yes 4) Eye protection: Yes 5) Protective clothing: No 6) Remediation while unoccupied: Yes 7) Vacation of adjacent areas: Advised if occupied by susceptible groups* 8) Containment required: Critical barriers 9) HEPA filtered negative air: No 10) Dust suppression: Misting 11) Bag contaminated materials: Yes 12) Post remediation cleaning of work area and egress: HEPA vacuum & clean with damp cloth &/or mop with a detergent solution. 13) Clearance testing: No

What is required for Level 1 Fungi (Mould) Remediation?

1) Minimum requirements for remediation overseers: Trained building staff. 2) Respiratory protection: N95 disposable respirator. 3) Gloves: Yes 4) Eye protection: Yes 5) Protective clothing: No 6) Remediation while unoccupied: Yes 7) Vacation of adjacent areas: Advised if occupied by susceptible groups* 8) Containment required: No 9) HEPA filtered negative air: No 10) Dust suppression: Misting 11) Bag contaminated materials: Yes 12) Post remediation cleaning of work area and egress: Clean with damp cloth and/or mop with detergent solution. 13) Clearance testing: No

When assessing the Filters of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Moisture. 2) Obvious microbial growth on filters. 3) Gaps between filters and housings. 4) Low efficiency filters.

What Occupations are at risk for encountering Glanders?

1) Pathologists 2) Horse trainers 3) Veterinary surgeons 4) Anyone in contact with sick horses or mules

What Occupations are at risk for encountering Psittacosis (in birds)?

1) Pet store employees 2) Gardeners 3) Veterinary surgeons 4) Research workers 5) Bird owners

What Occupations are at risk for encountering Ringworm?

1) Pet store employees 2) Stockmen 3) Cat and dog breeders

What Occupations are at risk for encountering Typhoid, Diphtheria, Streptococcal Sore Throat, Poliomyelitis?

1) Physicians and nurses 2) Pathologists 3) Laboratory and research workers

When assessing the Building Exterior, what should be considered in terms of sources that could affect Air Quality?

1) Poor grading or water drainage. 2) Evidence of water infiltration (discoloured building materials, furnishings). 3) Blocked rain gutters. 4) Openings in siding or veneer. 5) Damage to the building envelope (e.g. deteriorated bricks and mortar, opening in moisture barrier, flashing poorly fit). 6) Wood rot in structural timbers. 7) Animal or bird infestation near the building, in the crawl space below the building, or in the attic. 8) Automatic lawn sprinklers that keep the exterior walls wet.

When assessing Humidifiers and Air Washers of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Poorly maintained air washers or humidifiers (e.g. water spray systems with plugged nozzles). 2) Stagnant water in air washers or humidifiers. 3) Inaccessible humidifiers.

When assessing Carpets in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Poorly maintained or water-damaged carpet that serves as a "dirt trap". 2) Carpet in high traffic areas or near building entrances.

When assessing Fabric Office Partitions, Wall Coverings, and Upholstered Furniture in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Poorly maintained or water-damaged fabric-covered and upholstered items that act as sources for dirt accumulations and microbial growth.

When assessing Portable Humidifiers in an Occupied Space, what should be considered in terms of sources that could affect Air Quality?

1) Poorly maintained units (e.g. units not emptied and cleaned regularly). 2) Spray or mist units.

What Occupations are at risk for encountering Tuberculosis?

1) Silica workers 2) Large crowded facilities 3) People exposed to heat and organic dusts 4) Medical personnel.

What Occupations are at risk for encountering Q Fever?

1) Slaughterhouse workers 2) Farmers, and veterinary surgeons (cow, pig, sheep)

What is an example of a Level 1 Fungi (Mould) Remediation?

1) Small isolated areas (<10 sq. ft.) 2) Examples: Ceiling tiles, small areas on wall.

When assessing Supply Air Diffusers of an HVAC System, what should be considered in terms of sources that could affect Air Quality?

1) Surface deposits, rust, or microbial growth on louvres. 2) Particulate deposits or discoloration on adjacent ceilings and walls. 3) Poor air mixing.

How can Non-porous Materials be used to control Microbial Growth?

1) Vacuum the surfaces with a cleaner equipped with high efficiency particulate air (HEPA) filters or direct air exhaust to the outside 2) Wash the area with a dilute solution of biocide and detergent 3) Clean, thoroughly dry, and repaint

What Occupations are at risk for encountering Rabies?

1) Veterinarians 2) Laboratory research workers 3) Public service workers (e.g. postal carriers) 4) General public

What are the 9 major Kingdoms of Bioaerosols?

1) Viruses 2) Bacteria 3) Fungi 4) Protozoa 5) Algae 6) Vascular plants 7) Arthropods 8) Mammals 9) Birds

What procedures can be used for Laundry workers in Hospitals?

3) Carefully bag all linen instead of placing it in an open cart or in a closet. 4) Empty the contents of the bags directly into the washing machines.

During the Walkthrough Inspection, what does the Investigation Team do?

3) Examine all areas for signs of past or current water damage, excess moisture, or condensation problems.

What procedures can be used for Housekeeping workers in Hospitals?

3) Wet mopping and vacuuming with HEPA filtered vacuum cleaners are the best methods for cleaning floors. Dry sweeping stirs up dust that may contain microorganisms, and causes it to become airborne where it can be inhaled. Vacuuming with a normal vacuum cleaner does not collect fine dust particles. Like dry sweeping, it causes them to become airborne.

What procedures can be used for Housekeeping workers in Hospitals?

4) Detergents and disinfectants may lose their antimicrobial properties when left in solution in a mop bucket. Always use solutions immediately after mixing.

During the Walkthrough Inspection, what does the Investigation Team do?

4) Record all potential sources of indoor air contaminants. Discomfort or ailments described by occupants may be in part or completely due to exposure to contaminants other than microorganisms.

What procedures can be used for Laundry workers in Hospitals?

5) All employees who handle soiled laundry must wear appropriate protective equipment and clothing. This is covered in more detail in the previous section, under Universal Precautions. Sandals and shorts should never be worn.

What procedures can be used for Housekeeping workers in Hospitals?

5) Appropriate protective clothing such as gloves and splash goggles should be worn as required. (See universal precautions in previous section).

What Control Measures can be used to Prevent Microbial Growth in Buildings?

5) As noted, the factors that affect growth are moisture, temperature, air, and nutrients. These can be controlled to some extent.

During the Walkthrough Inspection, what does the Investigation Team do?

5) If required, develop a plan for a more in-depth investigation, or for remediation of problems identified during the walkthrough inspection.

What procedures can be used for Laundry workers in Hospitals?

6) Personnel who sort and fold clean linen may also be sources of infection due to poor personal hygiene. Proper hand washing is essential for all employees who handle clean and dirty linen. Protective gloves should be worn as well.

What procedures can be used for Laundry workers in Hospitals?

7) Washers and dryers must be vented to the outside, and seals around the doors must be in good condition so that aerosols containing microorganisms are not generated into the work environment.

What is a Decontamination Room or Unit?

A decontamination unit is constructed for entry into and exit from a remediation area. The unit may consist of one or several rooms, depending on the size of the project.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Humidifiers?

A dedicated steam system is preferable to steam from a central boiler. Chemical additives that may carry through into the steam are used in boilers.

What is Legionnaires' disease?

A form of atypical pneumonia caused by any type of Legionella bacteria. Signs and symptoms include cough, shortness of breath, high fever, muscle pains, and headaches. Nausea, vomiting, and diarrhea may also occur. This often begins two to ten days after being exposed. There is no vaccine. Prevention depends on good maintenance of water systems. Treatment of Legionnaires' Disease is with antibiotics. Recommended agents include fluoroquinolones, azithromycin, or doxycycline. The fatality rate of Legionnaires' disease has ranged from 5% to 30% during various outbreaks. The illness most often affects middle-aged and older persons, particularly those who smoke cigarettes or have chronic lung disease. Legionnaires' disease is usually spread by the breathing in of aerosolized water and soil contaminated with the Legionella bacteria. caused by Legionella pneumophila which is found in warm, stagnant water, such as hot water tanks, and spread by aerosolized routes from the environmental source to the client

What are Hypersensitivity Diseases?

A hypersensitivity disease is caused by exposure to an antigen, such as a bacteria, fungus, amoeba, or pollen. The initial exposures usually result in a mild reaction or no reaction at all.

What is a Decontamination Room or Unit?

A large scale decontamination unit usually has a work room, an equipment room, and an air lock.

What is Pontiac Fever?

A mild systemic disease with symptoms resembling influenza, probably caused by a legionella infection; mild flulike symptoms with legionella

What is an Obligate Parasite?

A parasite that cannot survive away from the host animal. All viruses, some bacteria, and a few fungi are obligate parasites and cannot live long outside a living host.

What Control Measures can be used to Prevent Microbial Growth in Buildings?

A plan for resolving and controlling problems related to microbial growth in buildings consists of four basic steps: 1) Identify and control the sources. 2) Remove and/or clean existing contamination. 3) Implement a long term plan to prevent recurrence. 4) Implement a cleaning and maintenance program

Historically, what types of Biohazards have Laboratory personnel encountered?

A review of historical documents shows that laboratory-associated cases of typhoid, cholera, glanders, brucellosis, and tetanus occurred around the beginning of the 20th century.

What is a Saphrophyte?

A saprophyte or saprotroph is an organism which gets its energy from dead and decaying organic matter. This may be decaying pieces of plants or animals. This means that saprophytes are heterotrophs. They are consumers in the food chain. This is the typical life-style of fungi. Some fungi are parasites on living organisms, but most are saprophytes. Many bacteria and protozoa are also saprophytes. To put it simply, most dead organic matter is eventually broken down and used by bacteria and fungi. Lastly, slime moulds are also saprophytes, as well as consuming bacteria.Examples of saprophytic bacteria include cheese mold, lactic acid, yeast and rotting kitchen waste. Saprophytic bacteria are fungal organisms that feed off of decaying organic matter. The term "saprophyte" refers specifically to fungal and bacterial saprotrophs, but animal saprotrophs are known as saprozoites. Other terms, such as 'saprotroph' or 'saprobe' may be used instead of saprophyte. Strictly speaking, -phyte means 'plant'. The problem is that no embryophytes (land plants) are true saprotrophs, and bacteria and fungi are no longer considered plants. Nevertheless, saprophyte is such a well-known term that most writers continue to use it .

What is an example of a Parasite?

A tapeworm living in the intestine of an animal or human is an example of a parasite.

What is a Vaccination?

A vaccine is a biological preparation that provides active acquired immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins. The agent stimulates the body's immune system to recognize the agent as a threat, destroy it, and to further recognize and destroy any of the microorganisms associated with that agent that it may encounter in the future. Vaccines can be prophylactic (example: to prevent or ameliorate the effects of a future infection by a natural or "wild" pathogen), or therapeutic (e.g., vaccines against cancer are being investigated). The administration of vaccines is called vaccination. Vaccination is the most effective method of preventing infectious diseases; widespread immunity due to vaccination is largely responsible for the worldwide eradication of smallpox and the restriction of diseases such as polio, measles, and tetanus from much of the world. The effectiveness of vaccination has been widely studied and verified; for example, vaccines that have proven effective include the influenza vaccine, the HPV vaccine, and the chicken pox vaccine. The World Health Organization (WHO) reports that licensed vaccines are currently available for twenty-five different preventable infections. The terms vaccine and vaccination are derived from Variolae vaccinae (smallpox of the cow), the term devised by Edward Jenner to denote cowpox. He used it in 1798 in the long title of his Inquiry into the Variolae vaccinae known as the Cow Pox, in which he described the protective effect of cowpox against smallpox. In 1881, to honor Jenner, Louis Pasteur proposed that the terms should be extended to cover the new protective inoculations then being developed.

Why would an inspection for Air Quality need to be conducted?

A workplace inspection might be conducted for several reasons such as: 1) Routine inspections to monitor general conditions for purposes of maintenance, and health and safety. These are often conducted by teams that consist of at least one member of the joint occupational health and safety committee and the management representative of each area being inspected.

What types of Administrative Controls should be used for protection against occupational exposure to blood and certain body fluids?

Administrative controls - reduce the likelihood of exposure by changing the way a task is done. For example: 1) hand washing 2) collecting and transporting fluids and tissues 3) handling of used needles and other sharps These are tasks that require special attention to ensure that they are conducted in the safest possible manner.

What is aflatoxin?

Aflatoxin converts guanine into thymine. It is released from a fungus Causes liver cancer Aflatoxins are poisonous carcinogens that are produced by certain molds (Aspergillus flavus and Aspergillus parasiticus) which grow in soil, decaying vegetation, hay, and grains. They are regularly found in improperly stored staple commodities such as cassava, chili peppers, corn, cotton seed, millet, peanuts, rice, sesame seeds, sorghum, sunflower seeds, tree nuts, wheat, and a variety of spices. When contaminated food is processed, aflatoxins enter the general food supply where they have been found in both pet and human foods, as well as in feedstocks for agricultural animals. Animals fed contaminated food can pass aflatoxin transformation products into eggs, milk products, and meat.

How can Viruses enter through the Alimentary Tract?

Alimentary tract - Viruses can enter the body by way of food or drink that is ingested, or in mucous from the respiratory tract. Polio virus is an example of a virus that enters the body by this route.

What disease do all Airborne Fungus Spores cause? What are the sources?

All airborne fungus spores cause Allergic Asthma and Rhinitis. Human exposure results from inhaled spores from damp organic material; and outdoor air.

What factors should be considered when deciding whether to use a Biocide?

All biocides are toxic substances. They should be used only when necessary, then selected and used with the health and safety of the maintenance personnel, building occupants, and the environment in mind.

What are Fungi?

All fungi are heterotrophs, which means they must have external food sources and cannot make their own carbohydrates from water and carbon dioxide, the way plants do.

What are examples of Hypersensitivity Diseases?

Allergic bronchopulmonary mycosis, asthma, allergic bronchopulmonary aspergillosis, hypersensitivity pneumonitis, rhinitis, and sinusitis are examples.

What is an Allergy?

Allergy is an acquired hypersensitivity to a particular substance. It is an antibody-antigen response that results in cell damage. The addition of complement to the antibody-antigen complex causes cell damage and inflammatory response.

What are features of Amoeba?

Amoebae are capable of ingesting gram negative bacteria and dissolved organic material. The gram negative bacteria, including Legionella species, remain alive inside the amoeba, protected from biocides and other environmental stresses.

What are Amoebae?

Amoebae are small (8-20 µ), unicellular organisms, with asymmetric bodies that constantly change shape by forming and retracting pseudopodia.

What is Water Activity (aw)?

Amount of water available to organisms. It is a measure of the water in a substrate that can be used by the fungus for growth.

How can Superficial Fungal Infections be hazardous?

An agricultural worker who did not wear proper shoes and other protective clothing developed this fungal infection.

How can Condensation in Building Envelops be controlled using Air Barriers (in Cold Climates)?

An air barrier is located on the warm side of the building envelope. It will help prevent the moisture in air from penetrating the building envelope.

What are Arthropods?

An arthropod is an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and paired jointed appendages. Arthropods form the phylum Euarthropoda, which includes insects, arachnids, myriapods, and crustaceans.

What factors control the Growth of Microorganisms in Buildings?

An environment that is good for humans is generally acceptable to fungi and bacteria and other microbials as well.

What is a saprophyte?

An organism that feeds on dead matter. Eat dead/decaying material (organic material) a; plant, fungus, or microorganism that lives on dead or decaying organic matter.

What are Antibodies?

Antibodies are special plasma proteins that can combine chemically with specific antigens. Our bodies do not contain antibodies for every conceivable antigen that might enter them. Antibodies are formed in response to the presence of the antigens.

What defense mechanisms are used against Viruses?

Antibody formation and phagocytosis are defense mechanisms against viruses. A third mechanism involving the production of interferon also plays a significant role.

What are Antigens?

Antigens involved in infection are usually bacterial toxins or proteins from the surface of the micro-organism, although components of almost any foreign cell can act as an antigen.

When are Antimicrobial Agents useful?

Antimicrobial agents may be useful in environments where it is difficult to control moisture. However, the use of antimicrobial products and materials does not eliminate the need for moisture control and an effective preventive maintenance program.

How do Saprophitic Microorganisms generate reservoirs of Bioaerosols?

Aspergillus flavus is an example of a saprophitic organism that lives outside on dead agricultural materials, can grow and become amplified on indoor substrates such as damp carpet, and can become disseminated, or airborne, when the carpet is disturbed.

What is Aspergillus fumigatus?

Aspergillus fumigatus is another fungus that is unlikely to affect a healthy person, but may cause infection in immunosuppressed persons.

What disease do Aspergillus Fungi cause? What are the sources?

Aspergillus fungi cause Invasive Aspergillosis; Aspergilloma; Allergic Bronchopulmonary Aspergillosis (ABPA); and Hypersensitivity Pneumonitis (HP). Human exposure results from inhaled spores from self-heated compost; damp organic material; and standing water.

What are Bacilli?

Bacilli - straight or curved rods.

What are Bacteria?

Bacteria are simple, one-celled organisms, with cell membranes but no organized nucleus or mitochondria. Most bacteria are complete cells and are capable of reproducing themselves. (All unicellular prokaryotic (no nucleus) organisms with peptidoglycan in their cell walls)

What Routes of Entry may Bacteria enter from?

Bacteria can exert toxic effects by inhalation, ingestion, or direct contact.

What are Bacterial Volatile Organic Compounds (VOCs)?

Bacteria produce VOCs, some of which are distinctive and apparent by odour at very low concentrations. Disagreeable body odours originate from bacteria that reside in perspiration on the skin surface.

How do Bacterial Infections occur?

Bacterial infections may occur by several mechanisms: 1) Ingesting food or water containing bacteria 2) Direct transfer of respiratory secretions or fecal material 3) Injection by foreign bodies and animal carriers 4) Inhalation of aerosols originating from the mouth or nose of an infected person

How do Bacteria and Viruses affect circulating White Blood Cell levels?

Bacterial infections usually result in increases of circulating granulocytic cells. Viral infections increase lymphocytes and decrease other white blood cells.

What Barriers for Protection should be used in Universal Precautions?

Barriers for protection against occupational exposure to blood and certain body fluids include personal protective equipment (PPE), engineering controls, and administrative controls.

What is a Bioaerosol?

Bioaerosols are airborne particles, large molecules, or volatile compounds that are living or were released from a living organism. Most bioaerosols are complex with respect to size and composition.

What are Bioaerosols?

Bioaerosols may be complex in terms of size and composition. For example, droplets released in coughs and sneezes may carry bacteria and viruses, as well as mucous and saliva. Bioaerosols may range in size from <0.1 - 100 µm (millionths of a metre).

What is the purpose of using Biocides in Mould Remediation?

Biocides are sometimes used to control extensive contamination, such as sewer backup. They are also used in fluid reservoirs, such as cooling towers, to prevent or control microbial growth. Biocides may be effective against one or more groups of microorganisms.

What are chemical properties of Biocides?

Biocides vary in stability, reactivity with materials, and their potential health hazard.

What workplaces have Biological Hazards found?

Biohazards may be unique to a particular occupation such as nursing or farming, and others, like the common cold, are potentially harmful to the general population.

What is the purpose of this module?

Biological hazards are often referred to as "biohazards". Biohazards are infectious agents that may be harmful to people or animals. They include bacteria, fungi, viruses, and parasites, and can cause diseases like tuberculosis, anthrax, rabies, and tick fever. Some are unique to certain occupations or areas, and some, like the common cold, can pose a threat to the general population. Biological hazardous agents can be transmitted by inhalation, injection, ingestion, or physical contact. We sometimes hear the term "bioaerosols" in reference to indoor air quality. Bioaerosols are airborne particles that are living or originate from living organisms. This means that fragments, metabolites, and waste products that originate from living organisms are included. This course discusses biohazard classes, associated diseases, and at risk occupations. It also provides practical advice for those who investigate health concerns and indoor air quality problems.

What are Biological Hazards?

Biological hazards or "biohazards" refer to infectious agents that may pose a risk to the health and well-being of people or animals.

How can you control Temperature in order to prevent Microbial Growth in Buildings?

Buildings are usually maintained at temperatures from 18°C to 24° C. This is also a good temperature range for many microorganisms. Microbial growth can sometimes be controlled in water systems by maintaining a temperature that is unacceptable for growth.

What is Interferon?

Chemical released by virus-infected body cells to interfere with the viruses ability to attack other body cells.

What is Chlamydia?

Chlamydia are also obligate parasites, bacterial in nature, but smaller even than rickettsia. Chlamydia is transmitted through air, and enters the body through the respiratory tract. The primary source of human infection is birds.

Why are Chlorine compounds such as Sodium Hypochlorite (Bleach) used as Biocides?

Chlorine compounds, such as sodium hypochlorite (household bleach), are widely used because they are effective against bacteria and fungi, deodorize, and are inexpensive.

What are Cocci?

Cocci - small spheres that look like a string of beads when magnified.

What is the Complement System?

Complement and antibodies also predispose bacteria to consumption (phagocytosis) by phagocytes in the vicinity.

How does Condensation form in Cold Climates?

Condensation can occur within the building envelope when warm, moist indoor air flows outward through cracks and holes. As the air travels through the wall towards the exterior, it gets colder and since cold air can hold less moisture, water falls out of it as condensation and causes insulation and wood inside the walls to become damp.

How can Condensation in Building Envelops be controlled in Cold Climates?

Condensation in building envelopes can be controlled by: 1) Insulation 2) Air barriers 3) Vapour barriers 4) Ventilation

How can you prevent Moisture being introduced through the control of Condensation?

Condensation on surfaces can be reduced by raising surface temperatures using the following methods: 1) Increase air flow to the surface by improving air circulation (e.g. move furniture, partitions, and other objects away from walls). 2) Reduce heat loss from a surface by insulating and sealing exterior walls.

How can Viruses enter through the Conjunctiva?

Conjunctiva - The conjunctiva is the delicate mucous membrane that lines the eyelids and covers the surface of the eyeball. Adeno and herpes are examples of viruses that cause conjunctivitis.

What is a Decontamination Room or Unit?

Contaminated debris is double bagged in heavy duty polyethylene, passed through the unit, and the bags are vacuumed with a HEPA vacuum before transporting through clean parts of the building.

For personnel who conduct Housekeeping in Hospitals, what hazards are present?

Contaminated disposable equipment, hypodermic needles, intravenous catheters, and other equipment that has been in contact with the blood and body fluids of infected individuals present potential hazards that are not always possible to avoid.

What is the most important factor to control when attempting to prevent Microbial Growth?

Control of moisture in buildings is the most critical variable that will prevent or limit microbial growth.

How can you control Moisture in order to prevent Microbial Growth in Buildings?

Control of moisture in buildings is the most critical variable that will prevent or limit microbial growth. Sources of moisture in a building and suitable control measures are described in the following sections.

What is a Critical Barrier?

Critical barriers must block all openings, including fixtures and HVAC system components such as supply air diffusers and return air grilles, to prevent the spread of dust and spores.

What disease do Cryptococcus Fungi cause? What are the sources?

Cryptococcus fungi cause Cryptococcosis. Human exposure results from inhaled spores from Bird droppings.

What effects can Mycotoxins produce?

Depending on the type of mycotoxin and the route of exposure, they may exert effects including skin rashes, mucous membrane irritation, dizziness, nausea, immuno-suppression, birth defects, and cancer.

How can Bacteria exert Toxic Effects through Direct Contact and Ingestion?

Direct contact and ingestion - Bacterial infections occur when the integrity of the skin is broken. Neglected cuts and scrapes may become infected by a mix of bacteria, dominated by staphylococci and streptococci.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Drain Pans?

Drain pans are located under cooling coils and in humidifier compartments. If the pans are not sloped properly, if the drains get plugged, or the capacity of the pans is not adequate, water will accumulate in the pans and may even overflow into the mechanical room.

How can Viruses enter through the Respiratory Tract?

Droplets with a diameter of 10 μm or more are trapped by nasal hairs in the nose, but those with a diameter of less than 5 μm are able to reach the deeper parts of the lungs. The body is equipped with a strong system of defense against foreign particles that are inhaled.

What occurs during a Walkthrough Inspection?

During a preliminary inspection, the investigators usually just look and listen. They may inspect the inside and outside of the building, informally interview building occupants, and review pertinent documents including specifications, the results of previous studies, and maintenance reports.

During the Walkthrough Inspection, what does the Investigation Team do?

During the walkthrough inspection, the investigation team will: 1) Check the physical structure of the building, maintenance routines, and how the building is occupied. 2) Look for signs of biological agents (e.g. deteriorated or discoloured building materials or furnishings).

How can you control Condensation in Cold Climates?

During winter in cold climates, maintaining enough humidity in the air is usually the biggest concern. It is often a struggle to maintain relative humidity at 30%.

For personnel who collect and clean Laundry in Hospitals, what hazards are present?

Employees who collect and clean linen may be exposed to pathogenic microorganisms. Exposure results from handling the linen of infected patients. It may be fouled by wound drainage and body wastes.

Can Amoeba cause Encephalitis?

Encephalitis has also occurred after exposure to airborne amoebae from soil.

What procedures can be used for Central Supply workers in Hospitals?

Enclosed and automated cleaners are used in many hospitals. They reduce contact with the instruments and the disinfecting agents.

What are Endotoxins?

Endotoxins are a part of the cell wall of gram-negative bacteria.

What types of Engineering Controls should be used for protection against occupational exposure to blood and certain body fluids?

Engineering controls - isolate or remove the hazard. Examples of engineering controls include: 1) sharps disposal containers 2) laser scalpels, 3) ventilation including laboratory fume hoods.

How can Condensation in Building Envelops be controlled using Insulation (in Cold Climates)?

Ensure that insulation in walls is adequate to prevent large temperature differences between indoor air and surfaces, and that insulation in exterior walls is properly installed to prevent thermal bridging or cold spots on interior surfaces.

What disease do Acanthamoeba cause?

Entry of the amoebae is thought to be by inhalation of airborne agents or through a skin lesion. Disease onset is insidious and the course is prolonged.

What hazards are associated with Hospitals?

Examples include bacterial infections such as streptococcus or staphylococcus, and viral infections including hepatitis, herpes, and influenza.

What are examples of Antimicrobial Agents?

Examples include paints, coatings, sealants, carpet material, ceiling tiles, and air filters. Antimicrobial agents are "bound" products.

What are examples of Zoonoses?

Examples of zoonoses include viral, bacterial, rickettsial, fungal, protozoan, and helminth diseases such as anthrax, brucellosis, tetanus, encephalitis, leptospiroses, Q-fever, rabies, and salmonellosis.

What are Exotoxins?

Exotoxins are proteins that are secreted to the environment and have not been found airborne.

What is Farmer's Lung?

Exposure to gram negative bacteria has been linked to HP, as well as asthma and hay fever. However, the cause-effect relationship is not clearly documented and there may be other factors involved.

What are the effects of Endotoxins if inhaled?

Exposure to low level airborne endotoxin concentrations is positive; it stimulates the immune system. At higher concentrations, endotoxins have an irritant effect. At very high concentrations, they can produce flu symptoms including fever and respiratory difficulties.

What Occupations are at risk for encountering Swineherd's Disease (virus in pigs)?

Farmers

How can Bacteria exert Toxic Effects through Direct Contact and Ingestion?

Food poisoning sometimes occurs in situations of mass feeding, such as in the military or school cafeterias. It is usually the result of incorrect handling. The main types of contamination are from the bacteria of the salmonella group, Clostridiumperfringens, and Staphylococcus aureus.

How is a Bioaerosol produced?

For an organism or its parts to become aerosolized, several events have to happen. 1) First, a reservoir is necessary. 2) Then the organism has to amplify, or increase in numbers. 3) Finally, the organism is disseminated, or aerosolized.

How do Arthropods (e.g. mites), Birds and Mammals generate reservoirs of Bioaerosols?

For example, a cat produces saliva, which is the reservoir, then licks its fur on which saliva accumulates or "amplifies", and afterwards when it scratches itself, the dried saliva flakes off into the air, or "disseminates".

What is a Bioaerosol?

For example, skin scales carry bacteria. Droplets from a contaminated humidifier may contain different types of bacteria, associated endotoxins, different species of fungi, dissolved antigens, and mycotoxins.

For personnel who conduct Housekeeping in Hospitals, what hazards are present?

For example, standard practice in hospitals is the use of clearly marked, rigid plastic containers for used needles and other sharps. Unfortunately, one sometimes gets left behind in bedding or disposed of in the regular garbage.

What are examples of Biocides?

For example, there are germicides, which are used to inactivate certain disease causing microorganisms; fungicides, which inactivate fungi; bactericides, which are effective against some types of bacteria; and viricides, which are effective against only specific viruses.

Why is Water important for Fungi?

For most fungi, the optimum aw is 0.90. If the building materials and furnishings of an indoor environment can be kept dry, fungal growth is less likely to become a problem.

Biosafety in Microbiological and Biomedical Laboratories

Four BSLs are described in Section 4, which consist of combinations of laboratory practices and techniques, safety equipment, and laboratory facilities. Each combination is specifically appropriate for the operations performed, the documented or suspected routes of transmission of the infectious agents, and the laboratory function or activity. The BSLs described in this manual should be differentiated from Risk Groups, as described in the NIH Guidelines and the World Health Organization Laboratory Biosafety Manual. Risk groups are the result of a classification of microbiological agents based on their association with, and resulting severity of, disease in humans. The risk group of an agent should be one factor considered in association with mode of transmission, procedural protocols, experience of staff, and other factors in determining the BSL in which the work will be conducted. The recommended biosafety level(s) for the organisms in Section VIII (Agent Summary Statements) represent those conditions under which the agent ordinarily can be safely handled. Of course, not all of the organisms capable of causing disease are included in Section VIII and an institution must be prepared to perform risk assessments for these agents using the best available information. Detailed information regarding the conduct of biological risk assessments can be found in Section II. The laboratory director is specifically and primarily responsible for assessing the risks and applying the appropriate biosafety levels. The institution's Biological Safety Officer (BSO) and IBC can be of great assistance in performing and reviewing the required risk assessment. At one point, under the NIH Guidelines, BSOs were required only when large-scale research or production of organisms containing recombinant DNA molecules was performed or when work with recombinant DNA molecules was conducted at BSL-3 or above. IBCs were required only when an institution was performing non-exempt recombinant DNA experiments. Today, however, it is strongly suggested that an institution conducting research or otherwise working with pathogenic agents have a BSO and properly constituted and functioning IBC. The responsibilities of each now extend beyond those described in the NIH Guidelines and depend on the size and complexity of the program. Generally, work with known agents should be conducted at the biosafety level recommended in Section VIII. When information is available to suggest that virulence, pathogenicity, antibiotic resistance patterns, vaccine and treatment availability, or other factors are significantly altered, more (or less) stringent practices may be specified. Often an increased volume or a high concentration of agent may require additional containment practices. Biosafety Level 1 practices, safety equipment, and facility design and construction are appropriate for undergraduate and secondary educational training and teaching laboratories, and for other laboratories in which work is done with defined and characterized strains of viable microorganisms not known to consistently cause disease in healthy adult humans. Bacillus subtilis, Nigeria gruberi, infectious canine hepatitis virus, and exempt organisms under the NIH Guidelines are representative of microorganisms meeting these criteria. Many agents not ordinarily associated with disease processes in humans are, however, opportunistic pathogens and may cause infection in the young, the aged, and immunodeficient or immunosuppressed individuals. Vaccine strains that have undergone multiple in vivo passages should not be considered avirulent simply because they are vaccine strains. BSL-1 represents a basic level of containment that relies on standard microbiological practices with no special primary or secondary barriers recommended, other than a sink for hand washing. Biosafety Level 2 practices, equipment, and facility design and construction are applicable to clinical, diagnostic, teaching, and other laboratories in which work is done with the broad spectrum of indigenous moderate-risk agents that are present in the community and associated with human disease of varying severity. With good microbiological techniques, these agents can be used safely in activities conducted on the open bench, provided the potential for producing splashes or aerosols is low. Hepatitis B virus, HIV, the Salmonella, and Toxoplasma are representative of microorganisms assigned to this containment level. BSL-2 is appropriate when work is done with any human-derived blood, body fluids, tissues, or primary human cell lines where the presence of an infectious agent may be unknown. (Laboratory personnel working with humanderived materials should refer to the OSHA Bloodborne Pathogen Standard2 for specific required precautions). Primary hazards to personnel working with these agents relate to accidental percutaneous or mucous membrane exposures, or ingestion of infectious materials. Extreme caution should be taken with contaminated needles or sharp instruments. Even though organisms routinely manipulated at BSL-2 are not known to be transmissible by the aerosol route, procedures with aerosol or high splash potential that may increase the risk of such personnel exposure must be conducted in primary containment equipment, or in devices such as a BSC or safety centrifuge cups. Personal protective equipment should be used as appropriate, such as splash shields, face protection, gowns, and gloves. Secondary barriers, such as hand washing sinks and waste decontamination facilities, must be available to reduce potential environmental contamination. Biosafety Level 3 practices, safety equipment, and facility design and construction are applicable to clinical, diagnostic, teaching, research, or production facilities in which work is done with indigenous or exotic agents with a potential for respiratory transmission, and which may cause serious and potentially lethal infection. Mycobacterium tuberculosis, St. Louis encephalitis virus, and Coxiella burnetii are representative of the microorganisms assigned to this level. Primary hazards to personnel working with these agents relate to autoinoculation, ingestion, and exposure to infectious aerosols. At BSL-3, more emphasis is placed on primary and secondary barriers to protect personnel in contiguous areas, the community, and the environment from exposure to potentially infectious aerosols. For example, all laboratory manipulations should be performed in a BSC or other enclosed equipment, such as a gas-tight aerosol generation chamber. Secondary barriers for this level include controlled access to the laboratory and ventilation requirements that minimize the release of infectious aerosols from the laboratory. Biosafety Level 4 practices, safety equipment, and facility design and construction are applicable for work with dangerous and exotic agents that pose a high individual risk of life-threatening disease, which may be transmitted via the aerosol route and for which there is no available vaccine or therapy. Agents with a close or identical antigenic relationship to BSL-4 agents also should be handled at this level. When sufficient data are obtained, work with these agents may continue at this level or at a lower level. Viruses such as Marburg or CongoCrimean hemorrhagic fever are manipulated at BSL-4. The primary hazards to personnel working with BSL-4 agents are respiratory exposure to infectious aerosols, mucous membrane or broken skin exposure to infectious droplets, and autoinoculation. All manipulations of potentially infectious diagnostic materials, isolates, and naturally or experimentally infected animals, pose a high risk of exposure and infection to laboratory personnel, the community, and the environment. The laboratory worker's complete isolation from aerosolized infectious materials is accomplished primarily by working in a Class III BSC or in a full-body, air-supplied positive-pressure personnel suit. The BSL-4 facility itself is generally a separate building or completely isolated zone with complex, specialized ventilation requirements and waste management systems to prevent release of viable agents to the environment. The laboratory director is specifically and primarily responsible for the safe operation of the laboratory. His/her knowledge and judgment are critical in assessing risks and appropriately applying these recommendations. The recommended biosafety level represents those conditions under which the agent can ordinarily be safely handled. Special characteristics of the agents used, the training and experience of personnel, procedures being conducted and the nature or function of the laboratory may further influence the director in applying these recommendations

Where can Amoeba be found?

Free-living amoebae are widely distributed in soil, on vegetation, and in water. Warm water in industrial process fluids, swimming pools, natural hot springs, and even poorly maintained eyewash stations are inviting habitats for amoebae. Acanthamoeba species have been identified in home humidifiers.

What diseases can Amoebae cause?

Free-living amoebae, particularly of the Naegleria and Acanthamoeba species, can cause fatal central nervous system infections. Healthy individuals have developed naegleria infections.

Where are Fungal Diseases encountered?

Fungal diseases may be contracted in a number of occupations including farming, outdoor work of any type, and animal and bird husbandry.

If a Flood occurs or Water Leaks in a Building, what concerns could arise?

Fungi are capable of germinating, growing, and sporulating within 24 hours after water damage occurs.

What are Fungi?

Fungi are derived from algae. They have no chlorophyll or any other pigment capable of photosynthesis, and are unable to synthesize protein or other organic material.

Where are Fungi found?

Fungi are dispersed mainly through air, and often over long distances.

How does Temperature affect Fungal growth?

Fungi are sometimes classified according to the temperature they grow well in. For example, most fungi are mesophilic, with an optimum temperature range of 15°C to 30° C.

What are features of Fungal Volatile Organic Compounds (VOCs)?

Fungi produce VOCs during growth and while degrading substrates. Some VOCs have distinctive odours and can be detected at very low concentrations. Many people find the odours offensive and disagreeable.

How can you control Condensation in Cold Climates?

Gaps in insulation or breaks in the moisture barrier result in cold spots on interior wall surfaces. Airborne spores deposited on the damp wall, which becomes the reservoir, soon amplify if conditions are right.

What are features of Glucan toxicity from Fungi?

Glucans can exert irritant effects. Exposure to it in dust has been associated with building related symptoms (BRS).

What is Hypersensitivity Pneumonitis characterized by?

HP is characterized by: 1) Recurrent pneumonia with fever, cough, and chest tightness; 2) A progression of cough, shortness of breath, fatigue, chronic lung fibrosis; 3) A pattern of acute and chronic lung disease

What is HVAC?

Heating, ventilating, and air conditioning system. An HVAC system in a building conditions, humidifies or dehumidifies air, and cleans it for comfort, health and safety.

What are features of (fungal) Histoplasma capsulatum as a Bioaerosol?

Histoplasma capsulatum is a dimorphic fungus that grows in soil exposed to bird feces or bat feces (guano) (top left). It can change forms to survive at different temperatures. In the outdoors, it typically grows as a mycelium (as shown in the micrograph, bottom left), but when the spores are inhaled (right), it responds to the high internal temperature of the body (37 °C [98.6 °F]) by turning into a yeast that can multiply in the lungs, causing the chronic lung disease histoplasmosis.

What disease do Histoplasma Fungi cause? What are the sources?

Histoplasma fungi cause Histoplasmosis. Human exposure results from inhaled spores from Bird droppings.

What is Histoplasmosis and Cryptococcus?

Histoplasmosis and cryptococcus are examples of diseases caused by intense exposures of airborne Histoplasma capsulatum or Cryptococcus neoformans. A healthy person might experience transient flu-like symptoms in response to infection. However, immunocompromised individuals are more susceptible to severe forms of the diseases.

What Occupations are at risk for encountering Infectious Hepatitis?

Hospital medical staff

What hazards are associated with Hospitals?

Hospitals portray an image of cleanliness and sterility. In reality, there are many potential biological hazards that may affect employees, patients, and visitors.

What are House Dust Mites?

House dust mites are arachnids, of the phylum Arthropoda. There are many mite species, besides house dust mites, found indoors. Some mites are parasitic on humans and other animals. The scabies mite is an example.

How do House Dust Mites produce Hypersensitivity Diseases?

House dust mites are mainly a concern in homes, but have been identified in office buildings as well. Hypersensitivity diseases caused by allergens from mites is a health concern.

What are features of House Dust Mites?

House dust mites feed on animal or vegetable waste and live in close association with their food sources.

For personnel who conduct Housekeeping in Hospitals, what hazards are present?

Housekeeping personnel may be the highest risk group of employees in the hospital. Handling contaminated equipment and general cleaning duties put them at risk of contact with blood and body fluids.

What procedures can be used for Central Supply workers in Hospitals?

However, it is essential that these units are vented to the outside, so that aerosols containing microorganisms are not generated into the workplace air.

How do Facultative Parasites generate reservoirs of Bioaerosols?

Human hosts can serve as reservoirs for these organisms. An example is the tuberculosis bacteria.

How do Bacteria cause Humidifier Fever?

Humidifier fever is thought to be caused by intermittent, high exposure to endotoxin. Endotoxin is the name for the toxin contained in the outer membrane of gram negative bacteria. Humidifier fever is a flu-like illness, characterized by fever, chills, muscle aches, malaise, and chest symptoms.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Humidifiers?

Humidifier manufacturers specify the distance required for complete entrainment of humidifier moisture by the ventilation air stream. Ensure that insulation and filters are located in the ducts within this distance.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Humidifiers?

Humidifier systems produce moisture that can end up being a problem. A humidifier must be carefully selected, installed, used, and maintained.

What is Hypersensitivity Pneumonitis?

Hypersensitivity pneumonitis or HP is also known as extrinsic allergic alveolitis. It is an inflammatory disease of the lung due to allergic reactions in the pulmonary tissues.

How can Dust Mites be harmful to Humans?

Hypersensitivity reactions to dust mites are caused by allergens in their feces and dried body parts. Temperature and relative humidity affect the breeding cycles of mites. Temperatures may fluctuate quickly within a home or building. Mattresses and couches are warmer than floors. Dust mite populations are greater in the warmer areas. In dry climates, fewer homes contain dust mites and where they exist, the populations are low.

What is the purpose of using Biocides in Mould Remediation?

If remedial measures are thorough, they will be effective, and there should be no need for a biocide. Biocides are chemical or physical agents that kill or deactivate microorganisms. They are used to treat existing microbial growth.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Cooling Coils?

If the ducts are lined with acoustic insulation, there is an increased risk of microbial growth.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Drain Pans?

If the water is left to stand, it will become stagnant and a reservoir for microorganisms.

What diseases can Amoebae cause?

Immunosuppressed people seem to be more susceptible to acanthamoeba infections.

How can Prevention and Cleaning Management be used to control Microbial Growth?

Implementing these practices may seem costly upon first consideration, but are actually cost effective when compared to the results of allowing systems and structures to deteriorate.

Historically, what types of Biohazards have Laboratory personnel encountered?

In 1941, 74 laboratory-associated cases of brucellosis infections occurred in the United States. Some of the cases were attributed to carelessness or poor technique.

Historically, what types of Biohazards have Laboratory personnel encountered?

In 1949, many cases occurred as a result of handling infected animals and tissues. In 1951, the majority of incidents were related to mouth pipetting and the use of needle and syringe.

Historically, what types of Biohazards have Laboratory personnel encountered?

In 1967, exposure to infectious aerosols was the most common cause. Brucellosis, tularemia, typhoid, and streptococcal infection were the leading diseases.

Historically, what types of Biohazards have Laboratory personnel encountered?

In 1974, the incidence of hepatitis in Danish clinical laboratories was seven times higher than the general population. Laboratory workers in England had a five times increased risk of getting tuberculosis compared with the general population.

For personnel who conduct Housekeeping in Hospitals, what hazards are present?

In either case, it is the housekeeping person who may be stuck by it. Vigilance to safe work procedures is essential.

In the case of complaints, or specific problems that appear to be building related, what is the first step when conducting an Air Quality Inspection?

In the case of complaints, or specific problems that appear to be building related, the first step is usually a preliminary inspection, which is often referred to as a "walkthrough" inspection.

What controls can be used in Hospitals?

In this section, laundry, housekeeping, central supply, and nursing will be discussed. Universal precautions should be applied wherever there is a risk of contact with blood or other body fluids.

How do Outdoor Environments act as sources of Bacteria?

Industries that use water-based coolants or recycled wash water may exhaust bacteria to the environment through their ventilation systems. Usually airborne bacteria does not survive long outdoors.

How do Agricultural workers get exposed to Zoonoses?

Infections can be transmitted directly by contact with the flesh or body fluids (blood, feces, urine, saliva) of the infected animal.

Where do infectious Bacterial Aerosols originate from?

Infectious aerosols may originate from: 1) Humans - e.g. tuberculosis 2) Environmental reservoirs - e.g. Legionnaires' disease 3) Animals - e.g. anthrax, brucellosis, psittacosis, Q-fever, tularemia

What are Zoonoses?

Infectious diseases that may be shared by animals and humans are generally referred to as zoonoses.

How do Obligate Parasites generate reservoirs of Bioaerosols?

Influenza is an example of a disease that is spread or "disseminated" by coughing and sneezing.

How can Bacteria exert Toxic Effects through Inhalation?

Inhalation - Bacteria produces exotoxins and endotoxins.

How can Condensation in Hot, Humid Environments be controlled using Insulation?

Insulation requirements are the same. (Ensure that insulation in walls is adequate to prevent large temperature differences between indoor air and surfaces, and that insulation in exterior walls is properly installed to prevent thermal bridging or cold spots on interior surfaces.)

What is Interferon?

Interferons (IFNs) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses. IFNs belong to the large class of proteins known as cytokines, molecules used for communication between cells to trigger the protective defenses of the immune system that help eradicate pathogens. Interferons are named for their ability to "interfere" with viral replication by protecting cells from virus infections. IFNs also have various other functions: they activate immune cells, such as natural killer cells and macrophages; they increase host defenses by up-regulating antigen presentation by virtue of increasing the expression of major histocompatibility complex (MHC) antigens. Certain symptoms of infections, such as fever, muscle pain and "flu-like symptoms", are also caused by the production of IFNs and other cytokines. More than twenty distinct IFN genes and proteins have been identified in animals, including humans. They are typically divided among three classes: Type I IFN, Type II IFN, and Type III IFN. IFNs belonging to all three classes are important for fighting viral infections and for the regulation of the immune system.

What are Antimicrobial Agents?

It is therefore important that the surface to be treated is cleaned before application.

How can Superficial Fungal Infections be hazardous?

Keratin is the fibrous protein component of epidermis tissues which are found in skin, nails, and hair. These fungi cause ringworm, athletes' foot, and jock-strap itch.

What are features of Environmental Bioaerosol reservoirs?

Legionella is a facultative parasite that lives in streams and soil water, can become amplified in a cooling tower, is then disseminated in the cooling water effluent, and invades living human cells to cause disease.

How do Bacteria cause Pontiac Fever?

Legionella species of bacteria are associated with two building related illnesses: Legionnaires' disease and Pontiac fever. Pontiac fever is a flu-like illness, with symptoms including fever, chills, headache, and muscle pains.

How do Bacteria cause Legionnaires' Disease?

Legionnaires' disease is a bacterial pneumonia.

How can Condensation in Building Envelops be controlled using Ventilation (in Cold Climates)?

Local exhaust ventilation and dilution ventilation can be used to reduce indoor moisture levels.

How can Condensation in Hot, Humid Environments be controlled using Pressure?

Maintain the building under positive pressure relative to the outdoors, so that unconditioned air does not enter through doors. This can be accomplished by putting more air into a building than the amount that is taken out (i.e. supply air volume exceeds exhaust air volume).

What factors control the Growth of Microorganisms in Buildings?

Many factors affect the growth of microorganisms in buildings. The requirements for growth are moisture, temperature, air, and nutrients.

Are Bacteria toxic?

Many of the bacteria that occupy the skin, respiratory tract, intestines, and other parts of the body are essential for human health. The risk of incurring illness or disease from environmental sources increases as bacteria concentrations increase.

What is Hypersensitivity Pneumonitis?

Many types of HP may occur in workers exposed to organic dusts: farmers, pigeon breeders, cheese makers, wood processors, and mushroom growers.

What Occupations are at risk for encountering Colds, Influenza, Scarlet Fever, Diphtheria, Smallpox?

May be contracted anywhere

What procedures can be used for Housekeeping workers in Hospitals?

Measures that should be employed to reduce the risk of exposure include the following: 1) Always put used needles and other sharps in specially marked containers. 2) Check bedding and other soiled laundry carefully while removing it.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Filters?

Microbial growth can be limited by: 1) Protecting filters from environmental conditions and replacing them regularly. 2) Ensuring that humidifiers in ventilation ducts are located at least 4.5 m from final filters. 3) Discarding wet filters immediately.

How can Non-porous Materials be used to control Microbial Growth?

Microbial growth that exists in a surface layer of condensation on painted walls or non-porous surfaces (including metal ductwork, metal studs, vinyl flooring, glass, ceramic tiles) can often be removed by following these steps:

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled?

Moisture accumulation and subsequent microbial growth can easily occur within the HVAC system components if the system is poorly designed or not maintained properly.

How can Moisture be introduced into the Building Envelope?

Moisture can accumulate on or inside a building envelope by leaks, capillary movement of water through porous materials, by gravitational flow of water, by the movement of humid air, or by diffusion of water vapour.

What are Facultative Parasites?

Most bacteria and some fungi are facultative parasites and can live and grow in or on living or non-living organic material.

How do Fungi produce Hypersensitivity Diseases?

Most fungi produce allergenic proteins called glycoproteins that can cause hypersensitivity diseases in susceptible hosts. Exposure to certain fungi is clearly associated with hay fever and asthma symptoms.

What are sources of Bacteria?

Most indoor and outdoor environments contain a profusion of bacteria. In general, human-source bacteria dominate the indoor environment, while most bacteria in the outdoor environment originates from the surfaces of living plants. Water is also a significant source of bacterial aerosols near oceans, lakes, ponds, and streams.

What are the cell walls of Fungi made of?

Most of the cell walls of fungi are composed of chitin, glucans and other polymers with extensive cross-linking between components.

Where are Phagocytic Cells located?

Most phagocytic cells are in the blood stream (white blood cells) or are closely associated with the blood or lymphatic systems. They are located in the lining cells of bone marrow, liver, spleen and other lymphatic tissue.

What are Mycotoxins?

Mycotoxins are chemical compounds that are produced during the fungal digestion process. Toxigenic fungi produce a series of these compounds which may vary greatly in structure.

How do Mycotoxins produce varying health effects?

Mycotoxins can produce different health effects by ingestion, inhalation, and skin contact.

For personnel who conduct Nursing in Hospitals, what hazards are present?

Nursing personnel usually have the most contact with patients. Without implementing appropriate precautionary measures, nurses are at risk of transmission of infection from the patient, they may be a source of infection to the patient, or they may transfer infection from one patient to another.

What occupational exposures are possible for Agriculture workers?

Occupational exposure to biohazards occurs in agriculture. The table at the beginning of Topic Three lists many of the diseases that may pose a risk to workers in the agricultural industry.

Why is it so difficult to control Humidity and Condensation in order to prevent Microbial growth (in Cold Climates)?

Often the humidity level ideal for occupant comfort is not possible to maintain without encountering microbial problems, due to the condition of the building envelope. This is a common problem in older buildings that are not as tight or well insulated as most modern buildings.

What disease can Naegleria Amoeba cause?

One species of Naegleria is known to cause primary amoebic meningoencephalitis (PAM), which is almost always fatal. The infections usually occur in children or young adults when engaged in a water sport or bathing in a spa.

How do Fungi cause disease in Humans?

Only a few fungi are able to invade living cells and cause infectious disease. Exposure to certain common outdoor fungi can cause infections in normal, healthy people who have not been previously infected.

What is Orf?

Orf, a viral dermatosis, is acquired from contact with infected sheep. Although hands are most often affected, the virus can be transmitted to other body parts.

How do Bacteria cause Organic Dust Toxic Syndrome (ODTS)?

Organic dust toxic syndrome (ODTS) is a condition similar to humidifier fever. It is diagnosed when short-term reactions follow exposures to high dust concentrations in composting and agricultural operations.

What is an example of a harmful Dust Mite?

Other mites transmit infectious diseases. For example, Rickettsial disease is transmitted from mice to humans by a mite called Liponyssoides sanguineus.

What are features of Environmental Bioaerosol reservoirs?

Others are found in environmental reservoirs, which can also act as amplifiers and disseminators.

How can Semi-porous Materials be used to control Microbial Growth?

Otherwise, the surface should be refinished to remove the contaminated portion. The structural element or piece of furniture should be discarded if microbial growth has affected its soundness.

How do Bacteria cause Pontiac Fever?

Outbreaks of Pontiac fever have been associated with contaminated air-conditioning systems, whirlpool spas, steam turbine condensers, and industrial coolants.

What Parasites cause significant infections for Humans?

Parasites that cause significant infections include: 1) protozoa 2) helminths 3) arthropods.

What are Facultative Parasites?

Parasites that normally have a free-living existence and establish a parasitic relationship with a host if the opportunity presents itself.

What are Helminths?

Parasitic worms, also known as helminths, are large macroparasites, which as adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels. There is no taxonomy of parasitic worms since it is an umbrella term that includes many species of worm from different genera, having parasitism as a commonality. These include two classes of the flatworm (Platyhelminthes) phylum, namely cestodes (tapeworms) and trematodes (flukes and blood flukes), many species of nematodes (roundworms), and the acanthocephalins known as thorny-headed worms. Some other parasitic worm species from the annelids (ringed worms), including the leeches, are ectoparasites and so are not classified as helminths which are endoparasites. Parasitic worms live in and feed in living hosts. They receive nourishment and protection while disrupting their hosts' nutrient absorption. This can cause weakness and disease of the host. In their adult form, parasitic worms cannot multiply in humans. Helminths are able to survive in their mammalian hosts for many years due to their ability to manipulate the immune response by secreting immunomodulatory products. All parasitic worms produce eggs for reproduction. These eggs have a strong shell that protects them against a range of environmental conditions. The eggs can therefore survive outside their hosts, in the environment for many months or years. Many, of the worms referred to as helminths belong to the group of intestinal parasites. An infection by a helminth is known as helminthiasis, helminth infection or intestinal worm infection. There is a naming convention which applies to all helminths: the ending "-asis" (or in veterinary science: "-osis") is added at the end of the name of the worm to denote the infection with that particular worm. For example, Ascaris is the name of a type of helminth, and ascariasis is the name of the infection caused by that helminth.

How can Amoeba be harmful to Humans?

Pathogenic amoebae cause serious health problems, particularly in tropical and Third World countries. Most cause gastrointestinal diseases transmitted by ingestion (e.g. giardiasis), or hematogenous diseases caused by insect carriers (e.g. malaria).

What symptoms do Penicillium Fungi cause? What are the sources?

Penicillium fungi act as Irritants. Human exposure results from inhaled VOCs from damp organic material.

What disease do Penicillium Fungi cause? What are the sources?

Penicillium fungi cause Hypersensitivity Pneumonitis (HP). Human exposure results from inhaled spores from damp organic material; and standing water.

How can Porous Materials be used to control Microbial Growth?

People who do the renovations and cleaning, and those in the area, may be at risk for developing hypersensitivity pneumonitis (HP) or other diseases and conditions described in this module if precautionary measures are not followed. Refer to guidelines on mould remediation for proper precautions to follow.

What types of Personal Protective Equipment should be used for protection against occupational exposure to blood and certain body fluids?

Personal protective equipment (PPE) - includes: 1) gloves 2) lab coats 3) gowns 4) goggles 5) glasses with side shields 6) masks 7) resuscitation bags

What is the Complement System?

Plasma proteins known as complement are normally present in plasma. Complement helps kill bacteria after an antibody has combined with its specific antigen in the wall of a bacterium. It does this by damaging the wall at the site of the antigen-antibody complex.

How can Porous Materials be used to control Microbial Growth?

Porous materials contaminated with microbial growth must be removed. Examples of porous materials include wallboard, carpet, upholstered furniture, ceiling tiles, and insulation. Carpets and drapes that can be removed for cleaning may be saved if they can be washed and dried, and if deterioration due to microbial growth has not been extensive.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Humidifiers?

Portable humidifiers are not recommended. They require frequent cleaning and disinfection, and are difficult to keep track of for maintenance in a large workplace.

How can you prevent Moisture being introduced into the Building Envelope?

Proper design of the building envelope will prevent this from happening.

What type of Toxic Properties are common with Altenuene Mycotoxins, commonly found in house dust? What species of fungus produces this?

Properties: 1) Anti-bacterial 2) Cytotoxic Produced by Alternaria alternata.

What type of Toxic Properties are common with Gliotoxin, commonly found in house dust?

Properties: 1) Carcinogenic Produced by Aspergillus fumigatus.

What type of Toxic Properties are common with Saratoxin H, commonly found in house dust?

Properties: 1) Gastrointestinally toxic Produced by Stachybotrys atra.

What type of Toxic Properties are common with Oxalic Acid, commonly found in house dust?

Properties: 1) Immunosuppressive 2) Genotoxic Produced by Rhizopus species.

What type of Toxic Properties are common with Sterigmatocystin, commonly found in house dust?

Properties: 1) Nephrotoxic 2) Hepatotoxic 3) Genotoxic Produced by Aspergillus versicolor.

What type of Toxic Properties are common with Viridicatum Toxin, commonly found in house dust?

Properties: 1) Nephrotoxic 2) Mutagenic Produced by Penicillium viridicatum.

What type of Toxic Properties are common with Ergot Alkaloids, commonly found in house dust?

Properties: 1) Neurotoxic Produced by Aspergillus fumigatus.

What type of Toxic Properties are common with Brevianamide A Mycotoxins, commonly found in house dust?

Properties: 1) Teratogenic Produced by Penicillium brevicompactum and Penicillium viridicatum.

What are Protozoa?

Protozoa (also protozoan, plural protozoans) is an informal term for single-celled eukaryotes, either free-living or parasitic, which feed on organic matter such as other microorganisms or organic tissues and debris. Since the protozoa, as traditionally defined, can no longer be regarded as "primitive animals" the terms "protists", "Protista" or "Protoctista" are sometimes preferred.

What diseases can Protozoa cause?

Protozoa can cause malaria, amebiasis, leishmaniasis, trypanosomiasis, and many other blood and gastrointestinal infections.

What are Pseudopodia?

Pseudopodia are projections with rounded ends that help with movement and feeding.

How do House Dust Mites produce Hypersensitivity Diseases?

Reactions to mites include chronic or recurrent rhinitis, allergic asthma, dermatitis, and conjunctivitis. In Western Europe, 5-10% of the population is estimated to have dust mite allergies.

How can you prevent Moisture being introduced through the control of Relative Humidity?

Relative humidity can be controlled by: 1) Providing local exhaust ventilation in areas where moisture is generated (e.g. washrooms, kitchens). 2) Dilute humid indoor air with outdoor air that is less humid. 3) Dehumidify indoor air by operating cooling coils in the HVAC system or by using console humidifiers.

How can Porous Materials be used to control Microbial Growth?

Removal and cleaning of contaminated materials should only be undertaken when proper procedures are followed. Disturbing contaminated materials usually results in bioaerosol release. Airborne spore concentrations may increase one thousand fold during remediation.

How do Fungi produce Hypersensitivity Diseases?

Research is showing that heavy, continuous, or repeated exposure to small fungal particles is essential to the development of HP. Genetic predisposition may also control susceptibility.

How do Obligate Parasites generate reservoirs of Bioaerosols?

Reservoirs of obligate parasitic organisms are usually contained in a living organism. For these organisms, amplification and dissemination occur inside the host.

How can Viruses enter through the Respiratory Tract?

Respiratory tract - The most common viral pathogens, including influenza, enter the host through the respiratory tract. The fate of the virus when it is inhaled depends on the anatomy of the host and the size of the droplet containing the virus.

What are Rickettsia?

Rickettsia are like bacteria, but smaller. They are obligate parasites, which means they depend on their host for the necessities of food and reproduction. Rickettsia are transmitted to people through blood-sucking arthropods including ticks, fleas, and lice. Typhus and Rocky Mountain spotted fever are examples of the diseases they can cause.

What are Saprophitic Microorganisms?

Saprophitic microorganisms include most fungi and many bacteria and protozoa.

Biosafety in Microbiological and Biomedical Laboratories

Section IV—Laboratory Biosafety Level Criteria The essential elements of the four biosafety levels for activities involving infectious microorganisms and laboratory animals are summarized in Table 2 of this section and discussed in Section 2. The levels are designated in ascending order, by degree of protection provided to personnel, the environment, and the community. Standard microbiological practices are common to all laboratories. Special microbiological practices enhance worker safety, environmental protection, and address the risk of handling agents requiring increasing levels of containment. Biosafety Level 1 Biosafety Level 1 is suitable for work involving well-characterized agents not known to consistently cause disease in immunocompetent adult humans, and present minimal potential hazard to laboratory personnel and the environment. BSL-1 laboratories are not necessarily separated from the general traffic patterns in the building. Work is typically conducted on open bench tops using standard microbiological practices. Special containment equipment or facility design is not required, but may be used as determined by appropriate risk assessment. Laboratory personnel must have specific training in the procedures conducted in the laboratory and must be supervised by a scientist with training in microbiology or a related science. The following standard practices, safety equipment, and facility requirements apply to BSL-1. A. Standard Microbiological Practices 1. The laboratory supervisor must enforce the institutional policies that control access to the laboratory. 2. Persons must wash their hands after working with potentially hazardous materials and before leaving the laboratory. 3. Eating, drinking, smoking, handling contact lenses, applying cosmetics, and storing food for human consumption must not be permitted in laboratory areas. Food must be stored outside the laboratory area in cabinets or refrigerators designated and used for this purpose. 4. Mouth pipetting is prohibited; mechanical pipetting devices must be used. 5. Policies for the safe handling of sharps, such as needles, scalpels, pipettes, and broken glassware must be developed and implemented. Whenever practical, laboratory supervisors should adopt improved engineering and work practice controls that reduce risk of sharps injuries.Precautions, including those listed below, must always be taken with sharp items. These include: a. Careful management of needles and other sharps are of primary importance. Needles must not be bent, sheared, broken, recapped, removed from disposable syringes, or otherwise manipulated by hand before disposal. b. Used disposable needles and syringes must be carefully placed in conveniently located puncture-resistant containers used for sharps disposal. c. Non-disposable sharps must be placed in a hard walled container for transport to a processing area for decontamination, preferably by autoclaving. d. Broken glassware must not be handled directly. Instead, it must be removed using a brush and dustpan, tongs, or forceps. Plastic ware should be substituted for glassware whenever possible. 6. Perform all procedures to minimize the creation of splashes and/or aerosols. 7. Decontaminate work surfaces after completion of work and after any spill or splash of potentially infectious material with appropriate disinfectant. 8. Decontaminate all cultures, stocks, and other potentially infectious materials before disposal using an effective method. Depending on where the decontamination will be performed, the following methods should be used prior to transport. a. Materials to be decontaminated outside of the immediate laboratory must be placed in a durable, leak proof container and secured for transport. b. Materials to be removed from the facility for decontamination must be packed in accordance with applicable local, state, and federal regulations. 9. A sign incorporating the universal biohazard symbol must be posted at the entrance to the laboratory when infectious agents are present. The sign may include the name of the agent(s) in use, and the name and phone number of the laboratory supervisor or other responsible personnel. Agent information should be posted in accordance with the institutional policy. 10. An effective integrated pest management program is required. (See Appendix G.) 11. The laboratory supervisor must ensure that laboratory personnel receive appropriate training regarding their duties, the necessary precautions to prevent exposures, and exposure evaluation procedures. Personnel must receive annual updates or additional training when procedural or policy changes occur. Personal health status may impact an individual's susceptibility to infection, ability to receive immunizations or prophylactic interventions. Therefore, all laboratory personnel and particularly women of childbearing age should be provided with information regarding immune competence and conditions that may predispose them to infection. Individuals having these conditions should be encouraged to self-identify to the institution's healthcare provider for appropriate counseling and guidance. B. Special Practices None required. C. Safety Equipment (Primary Barriers and Personal Protective Equipment) 1. Special containment devices or equipment, such as BSCs, are not generally required. 2. Protective laboratory coats, gowns, or uniforms are recommended to prevent contamination of personal clothing. 3. Wear protective eyewear when conducting procedures that have the potential to create splashes of microorganisms or other hazardous materials. Persons who wear contact lenses in laboratories should also wear eye protection. 4. Gloves must be worn to protect hands from exposure to hazardous materials. Glove selection should be based on an appropriate risk assessment. Alternatives to latex gloves should be available. Wash hands prior to leaving the laboratory. In addition, BSL-1 workers should: a. Change gloves when contaminated, glove integrity is compromised, or when otherwise necessary. b. Remove gloves and wash hands when work with hazardous materials has been completed and before leaving the laboratory. c. Do not wash or reuse disposable gloves. Dispose of used gloves with other contaminated laboratory waste. Hand washing protocols must be rigorously followed. D. Laboratory Facilities (Secondary Barriers) 1. Laboratories should have doors for access control. 2. Laboratories must have a sink for hand washing. 3. The laboratory should be designed so that it can be easily cleaned. Carpets and rugs in laboratories are not appropriate. 4. Laboratory furniture must be capable of supporting anticipated loads and uses. Spaces between benches, cabinets, and equipment should be accessible for cleaning. a. Bench tops must be impervious to water and resistant to heat, organic solvents, acids, alkalis, and other chemicals. b. Chairs used in laboratory work must be covered with a non-porous material that can be easily cleaned and decontaminated with appropriate disinfectant. 5. Laboratories windows that open to the exterior should be fitted with screens. Biosafety Level 2 Biosafety Level 2 builds upon BSL-1. BSL-2 is suitable for work involving agents that pose moderate hazards to personnel and the environment. It differs from BSL-1 in that: 1) laboratory personnel have specific training in handling pathogenic agents and are supervised by scientists competent in handling infectious agents and associated procedures; 2) access to the laboratory is restricted when work is being conducted; and 3) all procedures in which infectious aerosols or splashes may be created are conducted in BSCs or other physical containment equipment. The following standard and special practices, safety equipment, and facility requirements apply to BSL-2. A. Standard Microbiological Practices 1. The laboratory supervisor must enforce the institutional policies that control access to the laboratory. 2. Persons must wash their hands after working with potentially hazardous materials and before leaving the laboratory. 3. Eating, drinking, smoking, handling contact lenses, applying cosmetics, and storing food for human consumption must not be permitted in laboratory areas. Food must be stored outside the laboratory area in cabinets or refrigerators designated and used for this purpose. 4. Mouth pipetting is prohibited; mechanical pipetting devices must be used. 5. Policies for the safe handling of sharps, such as needles, scalpels, pipettes, and broken glassware must be developed and implemented. Whenever practical, laboratory supervisors should adopt improved engineering and work practice controls that reduce risk of sharps injuries. Precautions, including those listed below, must always be taken with sharp items. These include: a. Careful management of needles and other sharps are of primary importance. Needles must not be bent, sheared, broken, recapped, removed from disposable syringes, or otherwise manipulated by hand before disposal. b. Used disposable needles and syringes must be carefully placed in conveniently located puncture-resistant containers used for sharps disposal. c. Non-disposable sharps must be placed in a hard walled container for transport to a processing area for decontamination, preferably by autoclaving. d. Broken glassware must not be handled directly. Instead, it must be removed using a brush and dustpan, tongs, or forceps. Plastic ware should be substituted for glassware whenever possible. 6. Perform all procedures to minimize the creation of splashes and/or aerosols. 7. Decontaminate work surfaces after completion of work and after any spill or splash of potentially infectious material with appropriate disinfectant. 8. Decontaminate all cultures, stocks, and other potentially infectious materials before disposal using an effective method. Depending on where the decontamination will be performed, the following methods should be used prior to transport: a. Materials to be decontaminated outside of the immediate laboratory must be placed in a durable, leak proof container and secured for transport. b. Materials to be removed from the facility for decontamination must be packed in accordance with applicable local, state, and federal regulations. 9. A sign incorporating the universal biohazard symbol must be posted at the entrance to the laboratory when infectious agents are present. Posted information must include: the laboratory's biosafety level, the supervisor's name (or other responsible personnel), telephone number, and required procedures for entering and exiting the laboratory. Agent information should be posted in accordance with the institutional policy. 10. An effective integrated pest management program is required. (See Appendix G.) 11. The laboratory supervisor must ensure that laboratory personnel receive appropriate training regarding their duties, the necessary precautions to prevent exposures, and exposure evaluation procedures. Personnel must receive annual updates or additional training when procedural or policy changes occur. Personal health status may impact an individual's susceptibility to infection, ability to receive immunizations or prophylactic interventions. Therefore, all laboratory personnel and particularly women of childbearing age should be provided with information regarding immune competence and conditions that may predispose them to infection. Individuals having these conditions should be encouraged to self-identify to the institution's healthcare provider for appropriate counseling and guidance. B. Special Practices 1. All persons entering the laboratory must be advised of the potential hazards and meet specific entry/exit requirements. 2. Laboratory personnel must be provided medical surveillance, as appropriate, and offered available immunizations for agents handled or potentially present in the laboratory. 3. Each institution should consider the need for collection and storage of serum samples from at-risk personnel. 4. A laboratory-specific biosafety manual must be prepared and adopted as policy. The biosafety manual must be available and accessible. 5. The laboratory supervisor must ensure that laboratory personnel demonstrate proficiency in standard and special microbiological practices before working with BSL-2 agents. 6. Potentially infectious materials must be placed in a durable, leak proof container during collection, handling, processing, storage, or transport within a facility. 7. Laboratory equipment should be routinely decontaminated, as well as, after spills, splashes, or other potential contamination. a. Spills involving infectious materials must be contained, decontaminated, and cleaned up by staff properly trained and equipped to work with infectious material. b. Equipment must be decontaminated before repair, maintenance, or removal from the laboratory. 8. Incidents that may result in exposure to infectious materials must be immediately evaluated and treated according to procedures described in the laboratory biosafety manual. All such incidents must be reported to the laboratory supervisor. Medical evaluation, surveillance, and treatment should be provided and appropriate records maintained. 9. Animal and plants not associated with the work being performed must not be permitted in the laboratory. 10. All procedures involving the manipulation of infectious materials that may generate an aerosol should be conducted within a BSC or other physical containment devices. C. Safety Equipment (Primary Barriers and Personal Protective Equipment) 1. Properly maintained BSCs, other appropriate personal protective equipment, or other physical containment devices must be used whenever: a. Procedures with a potential for creating infectious aerosols or splashes are conducted. These may include pipetting, centrifuging, grinding, blending, shaking, mixing, sonicating, opening containers of infectious materials, inoculating animals intranasally, and harvesting infected tissues from animals or eggs. b. High concentrations or large volumes of infectious agents are used. Such materials may be centrifuged in the open laboratory using sealed rotor heads or centrifuge safety cups. 2. Protective laboratory coats, gowns, smocks, or uniforms designated for laboratory use must be worn while working with hazardous materials. Remove protective clothing before leaving for non-laboratory areas, e.g., cafeteria, library, and administrative offices). Dispose of protective clothing appropriately, or deposit it for laundering by the institution. It is recommended that laboratory clothing not be taken home. 3. Eye and face protection (goggles, mask, face shield or other splatter guard) is used for anticipated splashes or sprays of infectious or other hazardous materials when the microorganisms must be handled outside the BSC or containment device. Eye and face protection must be disposed of with other contaminated laboratory waste or decontaminated before reuse. Persons who wear contact lenses in laboratories should also wear eye protection. 4. Gloves must be worn to protect hands from exposure to hazardous materials. Glove selection should be based on an appropriate risk assessment. Alternatives to latex gloves should be available. Gloves must not be worn outside the laboratory. In addition, BSL-2 laboratory workers should: a. Change gloves when contaminated, glove integrity is compromised, or when otherwise necessary. b. Remove gloves and wash hands when work with hazardous materials has been completed and before leaving the laboratory. c. Do not wash or reuse disposable gloves. Dispose of used gloves with other contaminated laboratory waste. Hand washing protocols must be rigorously followed. 5. Eye, face and respiratory protection should be used in rooms containing infected animals as determined by the risk assessment. D. Laboratory Facilities (Secondary Barriers) 1. Laboratory doors should be self-closing and have locks in accordance with the institutional policies. 2. Laboratories must have a sink for hand washing. The sink may be manually, hands-free, or automatically operated. It should be located near the exit door. 3. The laboratory should be designed so that it can be easily cleaned and decontaminated. Carpets and rugs in laboratories are not permitted. 4. Laboratory furniture must be capable of supporting anticipated loads and uses. Spaces between benches, cabinets, and equipment should be accessible for cleaning. a. Bench tops must be impervious to water and resistant to heat, organic solvents, acids, alkalis, and other chemicals. b. Chairs used in laboratory work must be covered with a non-porous material that can be easily cleaned and decontaminated with appropriate disinfectant. 5. Laboratory windows that open to the exterior are not recommended. However, if a laboratory does have windows that open to the exterior, they must be fitted with screens. 6. BSCs must be installed so that fluctuations of the room air supply and exhaust do not interfere with proper operations. BSCs should be located away from doors, windows that can be opened, heavily traveled laboratory areas, and other possible airflow disruptions. 7. Vacuum lines should be protected with liquid disinfectant traps. 8. An eyewash station must be readily available. 9. There are no specific requirements for ventilation systems. However, planning of new facilities should consider mechanical ventilation systems that provide an inward flow of air without recirculation to spaces outside of the laboratory. 10. HEPA filtered exhaust air from a Class II BSC can be safely recirculation back into the laboratory environment if the cabinet is tested and certified at least annually and operated according to manufacturer's recommendations. BSCs can also be connected to the laboratory exhaust system by either a thimble (canopy) connection or directly exhausted to the outside through a hard connection. Provisions to assure proper safety cabinet performance and air system operation must be verified. 11. A method for decontaminating all laboratory wastes should be available in the facility (e.g., autoclave, chemical disinfection, incineration, or other validated decontamination method). Biosafety Level 3 Biosafety Level 3 is applicable to clinical, diagnostic, teaching, research, or production facilities where work is performed with indigenous or exotic agents that may cause serious or potentially lethal disease through the inhalation route of exposure. Laboratory personnel must receive specific training in handling pathogenic and potentially lethal agents, and must be supervised by scientists competent in handling infectious agents and associated procedures. All procedures involving the manipulation of infectious materials must be conducted within BSCs or other physical containment devices. A BSL-3 laboratory has special engineering and design features. The following standard and special safety practices, equipment, and facility requirements apply to BSL-3. A. Standard Microbiological Practices 1. The laboratory supervisor must enforce the institutional policies that control access to the laboratory. 2. Persons must wash their hands after working with potentially hazardous materials and before leaving the laboratory. 3. Eating, drinking, smoking, handling contact lenses, applying cosmetics, and storing food for human consumption must not be permitted in laboratory areas. Food must be stored outside the laboratory area in cabinets or refrigerators designated and used for this purpose. 4. Mouth pipetting is prohibited; mechanical pipetting devices must be used. 5. Policies for the safe handling of sharps, such as needles, scalpels, pipettes, and broken glassware must be developed and implemented. Whenever practical, laboratory supervisors should adopt improved engineering and work practice controls that reduce risk of sharps injuries. Precautions, including those listed below, must always be taken with sharp items. These include: a. Careful management of needles and other sharps are of primary importance. Needles must not be bent, sheared, broken, recapped, removed from disposable syringes, or otherwise manipulated by hand before disposal. b. Used disposable needles and syringes must be carefully placed in conveniently located puncture-resistant containers used for sharps disposal. c. Non-disposable sharps must be placed in a hard walled container for transport to a processing area for decontamination, preferably by autoclaving. d. Broken glassware must not be handled directly. Instead, it must be removed using a brush and dustpan, tongs, or forceps. Plastic ware should be substituted for glassware whenever possible. 6. Perform all procedures to minimize the creation of splashes and/or aerosols. 7. Decontaminate work surfaces after completion of work and after any spill or splash of potentially infectious material with appropriate disinfectant. 8. Decontaminate all cultures, stocks, and other potentially infectious materials before disposal using an effective method. A method for decontaminating all laboratory wastes should be available in the facility, preferably within the laboratory (e.g., autoclave, chemical disinfection, incineration, or other validated decontamination method). Depending on where the decontamination will be performed, the following methods should be used prior to transport: a. Materials to be decontaminated outside of the immediate laboratory must be placed in a durable, leak proof container and secured for transport. b. Materials to be removed from the facility for decontamination must be packed in accordance with applicable local, state, and federal regulations. 9. A sign incorporating the universal biohazard symbol must be posted at the entrance to the laboratory when infectious agents are present. Posted information must include the laboratory's biosafety level, the supervisor's name (or other responsible personnel), telephone number, and required procedures for entering and exiting the laboratory. Agent information should be posted in accordance with the institutional policy. 10. An effective integrated pest management program is required. (See Appendix G.) 11. The laboratory supervisor must ensure that laboratory personnel receive appropriate training regarding their duties, the necessary precautions to prevent exposures, and exposure evaluation procedures. Personnel must receive annual updates or additional training when procedural or policy changes occur. Personal health status may impact an individual's susceptibility to infection, ability to receive immunizations or prophylactic interventions. Therefore, all laboratory personnel and particularly women of childbearing age should be provided with information regarding immune competence and conditions that may predispose them to infection. Individuals having these conditions should be encouraged to self-identify to the institution's healthcare provider for appropriate counseling and guidance. B. Special Practices 1. All persons entering the laboratory must be advised of the potential hazards and meet specific entry/exit requirements. 2. Laboratory personnel must be provided medical surveillance and offered appropriate immunizations for agents handled or potentially present in the laboratory. 3. Each institution should consider the need for collection and storage of serum samples from at-risk personnel. 4. A laboratory-specific biosafety manual must be prepared and adopted as policy. The biosafety manual must be available and accessible. 5. The laboratory supervisor must ensure that laboratory personnel demonstrate proficiency in standard and special microbiological practices before working with BSL-3 agents. 6. Potentially infectious materials must be placed in a durable, leak proof container during collection, handling, processing, storage, or transport within a facility. 7. Laboratory equipment should be routinely decontaminated, as well as, after spills, splashes, or other potential contamination. a. Spills involving infectious materials must be contained, decontaminated, and cleaned up by staff properly trained and equipped to work with infectious material. b. Equipment must be decontaminated before repair, maintenance, or removal from the laboratory. 8. Incidents that may result in exposure to infectious materials must be immediately evaluated and treated according to procedures described in the laboratory biosafety manual. All such incidents must be reported to the laboratory supervisor. Medical evaluation, surveillance, and treatment should be provided and appropriate records maintained. 9. Animals and plants not associated with the work being performed must not be permitted in the laboratory. 10. All procedures involving the manipulation of infectious materials must be conducted within a BSC, or other physical containment devices. No work with open vessels is conducted on the bench. When a procedure cannot be performed within a BSC, a combination of personal protective equipment and other containment devices, such as a centrifuge safety cup or sealed rotor must be used. C. Safety Equipment (Primary Barriers and Personal Protective Equipment) 1. All procedures involving the manipulation of infectious materials must be conducted within a BSC (preferably Class II or Class III), or other physical containment devices. 2. Workers in the laboratory where protective laboratory clothing with a solid-front, such as tie-back or wrap-around gowns, scrub suits, or coveralls. Protective clothing is not worn outside of the laboratory. Reusable clothing is decontaminated before being laundered. Clothing is changed when contaminated. 3. Eye and face protection (goggles, mask, face shield or other splash guard) is used for anticipated splashes or sprays of infectious or other hazardous materials. Eye and face protection must be disposed of with other contaminated laboratory waste or decontaminated before reuse. Persons who wear contact lenses in laboratories must also wear eye protection. 4. Gloves must be worn to protect hands from exposure to hazardous materials. Glove selection should be based on an appropriate risk assessment. Alternatives to latex gloves should be available. Gloves must not be worn outside the laboratory. In addition, BSL-3 laboratory workers: a. Changes gloves when contaminated, glove integrity is compromised, or when otherwise necessary. Wear two pairs of gloves when appropriate. b. Remove gloves and wash hands when work with hazardous materials has been completed and before leaving the laboratory. c. Do not wash or reuse disposable gloves. Dispose of used gloves with other contaminated laboratory waste. Hand washing protocols must be rigorously followed. 5. Eye, face, and respiratory protection must be used in rooms containing infected animals. D. Laboratory Facilities (Secondary Barriers) 1. Laboratory doors must be self-closing and have locks in accordance with the institutional policies. The laboratory must be separated from areas that are open to unrestricted traffic flow within the building. Laboratory access is restricted. Access to the laboratory is through two self-closing doors. A clothing change room (anteroom) may be included in the passageway between the two self-closing doors. 2. Laboratories must have a sink for hand washing. The sink must be hands-free or automatically operated. It should be located near the exit door. If the laboratory is segregated into different laboratories, a sink must also be available for hand washing in each zone. Additional sinks may be required as determined by the risk assessment. 3. The laboratory must be designed so that it can be easily cleaned and decontaminated. Carpets and rugs are not permitted. Seams, floors, walls, and ceiling surfaces should be sealed. Spaces around doors and ventilation openings should be capable of being sealed to facilitate space decontamination. a. Floors must be slip resistant, impervious to liquids, and resistant to chemicals. Consideration should be given to the installation of seamless, sealed, resilient or poured floors, with integral cove bases. b. Walls should be constructed to produce a sealed smooth finish that can be easily cleaned and decontaminated. c. Ceilings should be constructed, sealed, and finished in the same general manner as walls. Decontamination of the entire laboratory should be considered when there has been gross contamination of the space, significant changes in laboratory usage, for major renovations, or maintenance shut downs. Selection of the appropriate materials and methods used to decontaminate the laboratory must be based on the risk assessment. 4. Laboratory furniture must be capable of supporting anticipated loads and uses. Spaces between benches, cabinets, and equipment must be accessible for cleaning. a. Bench tops must be impervious to water and resistant to heat, organic solvents, acids, alkalis, and other chemicals. b. Chairs used in laboratory work must be covered with a non-porous material that can be easily cleaned and decontaminated with appropriate disinfectant. 5. All windows in the laboratory must be sealed. 6. BSCs must be installed so that fluctuations of the room air supply and exhaust do not interfere with proper operations. BSCs should be located away from doors, heavily traveled laboratory areas, and other possible airflow disruptions. 7. Vacuum lines must be protected with HEPA filters, or their equivalent. Filters must be replaced as needed. Liquid disinfectant traps may be required. 8. An eyewash station must be readily available in the laboratory. 9. A ducted air ventilation system is required. This system must provide sustained directional airflow by drawing air into the laboratory from "clean" areas toward "potentially contaminated" areas. The laboratory shall be designed such that under failure conditions the airflow will not be reversed. a. Laboratory personnel must be able to verify directional airflow. A visual monitoring device, which confirms directional airflow, must be provided at the laboratory entry. Audible alarms should be considered to notify personnel of air flow disruption. b. The laboratory exhaust air must not re-circulate to any other area of the building. c. The laboratory building exhaust air should be dispersed away from occupied areas and from building air intake locations or the exhaust air must be HEPA filtered. HEPA filter housings should have gas-tight isolation dampers, decontamination ports, and/or bag-in/bag-out (with appropriate decontamination procedures) capability. The HEPA filter housing should allow for leak testing of each filter and assembly. The filters and the housing should be certified at least annually. 10. HEPA filtered exhaust air from a Class II BSC can be safely re-circulated into the laboratory environment if the cabinet is tested and certified at least annually and operated according to manufacturer's recommendations. BSCs can also be connected to the laboratory exhaust system by either a thimble (canopy) connection or directly exhausted to the outside through a hard connection. Provisions to assure proper safety cabinet performance and air system operation must be verified. BSCs should be certified at least annually to assure correct performance. Class III BSCs must be directly (hard) connected up through the second exhaust HEPA filter of the cabinet. Supply air must be provided in such a manner that prevents positive pressurization of the cabinet. 11. A method for decontaminating all laboratory wastes should be available in the facility, preferably within the laboratory (e.g., autoclave, chemical disinfection, or other validated decontamination method). 12. Equipment that may produce infectious aerosols must be contained in primary barrier devices that exhaust air through HEPA filtration or other equivalent technology before being discharged into the laboratory. These HEPA filters should be tested and/or replaced at least annually. 13. Facility design consideration should be given to means of decontaminating large pieces of equipment before removal from the laboratory. 14. Enhanced environmental and personal protection may be required by the agent summary statement, risk assessment, or applicable local, state, or federal regulations. These laboratory enhancements may include, for example, one or more of the following: an anteroom for clean storage of equipment and supplies with dress-in, shower-out capabilities; gas tight dampers to facilitate laboratory isolation; final HEPA filtration of the laboratory exhaust air; laboratory effluent decontamination; and advanced access control devices, such as biometrics. 15. The BSL-3 facility design, operational parameters, and procedures must be verified and documented prior to operation. Facilities must be re-verified and documented at least annually. Biosafety Level 4 Biosafety Level 4 is required for work with dangerous and exotic agents that pose a high individual risk of aerosol-transmitted laboratory infections and life-threatening disease that is frequently fatal, for which there are no vaccines or treatments, or a related agent with unknown risk of transmission. Agents with a close or identical antigenic relationship to agents requiring BSL-4 containment must be handled at this level until sufficient data are obtained either to confirm continued work at this level, or re-designate the level. Laboratory staff must have specific and thorough training in handling extremely hazardous infectious agents. Laboratory staff must understand the primary and secondary containment functions of standard and special practices, containment equipment, and laboratory design characteristics. All laboratory staff and supervisors must be competent in handling agents and procedures requiring BSL-4 containment. The laboratory supervisor in accordance with institutional policies controls access to the laboratory. There are two models for BSL-4 laboratories: 1. A Cabinet Laboratory—Manipulation of agents must be performed in a Class III BSC; and 2. A Suit Laboratory—Personnel must wear a positive pressure supplied air protective suit. BSL-4 cabinet and suit laboratories have special engineering and design features to prevent microorganisms from being disseminated into the environment. The following standard and special safety practices, equipment, and facilities apply to BSL-4. A. Standard Microbiological Practices 1. The laboratory supervisor must enforce the institutional policies that control access to the laboratory. 2. Eating, drinking, smoking, handling contact lenses, applying cosmetics, and storing food for human consumption must not be permitted in laboratory areas. Food must be stored outside the laboratory area in cabinets or refrigerators designated and used for this purpose. 3. Mechanical pipetting devices must be used. 4. Policies for the safe handling of sharps, such as needles, scalpels, pipettes, and broken glassware must be developed and implemented. Precautions, including those listed below, must be taken with any sharp items. These include: a. Broken glassware must not be handled directly. Instead, it must be removed using a brush and dustpan, tongs, or forceps. Plastic ware should be substituted for glassware whenever possible. b. Use of needles and syringes or other sharp instruments should be restricted in the laboratory, except when there is no practical alternative. c. Used needles must not be bent, sheared, broken, recapped, removed from disposable syringes, or otherwise manipulated by hand before disposal or decontamination. Used disposable needles must be carefully placed in puncture-resistant containers used for sharps disposal, located as close to the point of use as possible. d. Whenever practical, laboratory supervisors should adopt improved engineering and work practice controls that reduce risk of sharps injuries. 5. Perform all procedures to minimize the creation of splashes and/or aerosols. 6. Decontaminate work surfaces with appropriate disinfectant after completion of work and after any spill or splash of potentially infectious material. 7. Decontaminate all wastes before removal from the laboratory by an effective and validated method. 8. A sign incorporating the universal biohazard symbol must be posted at the entrance to the laboratory when infectious agents are present. Posted information must include the laboratory's biosafety level, the supervisor's name (or other responsible personnel), telephone number, and required procedures for entering and exiting the laboratory. Agent information should be posted in accordance with the institutional policy. 9. An effective integrated pest management program is required. (See Appendix G.) 10. The laboratory supervisor must ensure that laboratory personnel receive appropriate training regarding their duties, the necessary precautions to prevent exposures, and exposure evaluation procedures. Personnel must receive annual updates or additional training when procedural or policy changes occur. Personal health status may impact an individual's susceptibility to infection, ability to receive immunizations or prophylactic interventions. Therefore, all laboratory personnel and particularly women of childbearing age should be provided with information regarding immune competence and conditions that may predispose them to infection. Individuals having these conditions should be encouraged to self-identify to the institution's healthcare provider for appropriate counseling and guidance. B. Special Practices 1. All persons entering the laboratory must be advised of the potential hazards and meet specific entry requirements in accordance with institutional policies. Only persons whose presence in the facility or individual laboratory rooms is required for scientific or support purposes are authorized to enter. Entry into the facility must be limited by means of secure, locked doors. A logbook, or other means of documenting the date and time of all persons entering and leaving the laboratory must be maintained. While the laboratory is operational, personnel must enter and exit the laboratory through the clothing change and shower rooms except during emergencies. All personal clothing must be removed in the outer clothing change room. All persons entering the laboratory must use laboratory clothing, including undergarments, pants, shirts, jumpsuits, shoes, and gloves (as appropriate). All persons leaving the laboratory must take a personal body shower. Used laboratory clothing must not be removed from the inner change room through the personal shower. These items must be treated as contaminated materials and decontaminated before laundering. After the laboratory has been completely decontaminated and all infectious agents are secured, necessary staff may enter and exit without following the clothing change and shower requirements described above. 2. Laboratory personnel and support staff must be provided appropriate occupational medical services including medical surveillance and available immunizations for agents handled or potentially present in the laboratory. A system must be established for reporting and documenting laboratory accidents, exposures, employee absenteeism and for the medical surveillance of potential laboratory-associated illnesses. An essential adjunct to such an occupational medical services system is the availability of a facility for the isolation and medical care of personnel with potential or known laboratory-acquired infections. 3. Each institution should consider the need for collection and storage of serum samples from at-risk personnel. 4. A laboratory-specific biosafety manual must be prepared. The biosafety manual must be available, accessible, and followed. 5. The laboratory supervisor is responsible for ensuring that laboratory personnel: a. Demonstrate high proficiency in standard and special microbiological practices, and techniques for working with agents requiring BSL-4 containment. b. Receive appropriate training in the practices and operations specific to the laboratory facility. c. Receive annual updates and additional training when procedural or policy changes occur. 6. Removal of biological materials that are to remain in a viable or intact state from the laboratory must be transferred to a non-breakable, sealed primary container and then enclosed in a non-breakable, sealed secondary container. These materials must be transferred through a disinfectant dunk tank, fumigation chamber, or decontamination shower. Once removed, packaged viable material must not be opened outside BSL-4 containment unless inactivated by a validated method. 7. Laboratory equipment musts be routinely decontaminated, as well as after spills, splashes, or other potential contamination. a. Spills involving infectious materials must be contained, decontaminated, and cleaned up by appropriate professional staff, or others properly trained and equipped to work with infectious material. A spill procedure must be developed and posted within the laboratory. b. Equipment must be decontaminated using an effective and validated method before repair, maintenance, or removal from the laboratory. The interior of the Class III cabinet as well as all contaminated plenums, fans and filters must be decontaminated using a validated gaseous or vapor method. c. Equipment or material that might be damaged by high temperatures or steam must be decontaminated using an effective and validated procedure such as a gaseous or vapor method in an airlock or chamber designed for this purpose. 8. Incidents that may result in exposure to infectious materials must be immediately evaluated and treated according to procedures described in the laboratory biosafety manual. All incidents must be reported to the laboratory supervisor, institutional management and appropriate laboratory personnel as defined in the laboratory biosafety manual. Medical evaluation, surveillance, and treatment should be provided and appropriate records maintained. 9. Animals and plants not associated with the work being performed must not be permitted in the laboratory. 10. Supplies and materials that are not brought into the BSL-4 laboratory through the change room, must be brought in through a previously decontaminated double-door autoclave, fumigation chamber, or airlock. After securing the outer doors, personnel within the laboratory retrieve the materials by opening the interior doors of the autoclave, fumigation chamber, or airlock. These doors must be secured after materials are brought into the facility. The doors of the autoclave or fumigation chamber are interlocked in a manner that prevents opening of the outer door unless the autoclave or fumigation chamber has been operated through a decontamination cycle. Only necessary equipment and supplies should be stored inside the BSL-4 laboratory. All equipment and supplies taken inside the laboratory must be decontaminated before removal from the laboratory. 11. Daily inspections of essential containment and life support systems must be completed and documented before laboratory work is initiated to ensure that the laboratory is operating according to established parameters. 12. Practical and effective protocols for emergency situations must be established. These protocols must include plans for medical emergencies, facility malfunctions, fires, escape of animals within the laboratory, and other potential emergencies. Training in emergency response procedures must be provided to emergency response personnel and other responsible staff according to institutional policies. C. Safety Equipment (Primary Barriers and Personal Protective Equipment) Cabinet Laboratory 1. All manipulations of infectious materials within the laboratory must be conducted in the Class III biological safety cabinet. Double-door, pass through autoclaves must be provided for decontaminating materials passing out of the Class III BSC(s). The autoclave doors must be interlocked so that only one can be opened at any time and be automatically controlled so that the outside door to the autoclave can only be opened after the decontamination cycle has been completed. The Class III cabinet must also have a pass-through dunk tank, fumigation chamber, or equivalent decontamination method so that materials and equipment that cannot be decontaminated in the autoclave can be safely removed from the cabinet. Containment must be maintained at all times. The Class III cabinet must have a HEPA filter on the supply air intake and two HEPA filters in series on the exhaust outlet of the unit. There must be gas tight dampers on the supply and exhaust ducts of the cabinet to permit gas or vapor decontamination of the unit. Ports for injection of test medium must be present on all HEPA filter housings. The interior of the Class III cabinet must be constructed with smooth finishes that can be easily cleaned and decontaminated. All sharp edges on cabinet finishes must be eliminated to reduce the potential for cuts and tears of gloves. Equipment to be placed in the Class III cabinet should also be free of sharp edges or other surfaces that may damage or puncture the cabinet gloves. Class III cabinet gloves must be inspected for damage prior to use and changed if necessary. Gloves should be replaced annually during cabinet re-certification. The cabinet should be designed to permit maintenance and repairs of cabinet mechanical systems (refrigeration, incubators, centrifuges, etc.) to be performed from the exterior of the cabinet whenever possible. Manipulation of high concentrations or large volumes of infectious agents within the Class III cabinet should be performed using physical containment devices inside the cabinet whenever practical. Such materials should be centrifuged inside the cabinet using sealed rotor heads or centrifuge safety cups. The Class III cabinet must be certified at least annually. 2. Workers in the laboratory must wear protective laboratory clothing with a solid-front, such as tie-back or wrap-around gowns, scrub suits, or coveralls. No personal clothing, jewelry, or other items except eyeglasses should be taken past the personal shower area. All protective clothing must be removed in the dirty side change room before showering. Reusable clothing must be autoclaved prior to removal from the laboratory for laundering. 3. Eye, face and respiratory protection should be used in rooms containing infected animals as determined by the risk assessment. Prescription eyeglasses must be decontaminated before removal through the personal body shower. 4. Disposable gloves must be worn underneath cabinet gloves to protect the worker from exposure should a break or tear occur in a cabinet glove. Gloves must not be worn outside the laboratory. Alternatives to latex gloves should be available. Do not wash or reuse disposable gloves. Dispose of used gloves with other contaminated laboratory waste. Suit Laboratory 1. All procedures must be conducted by personnel wearing a one-piece positive pressure supplied air suit. All manipulations of infectious agents must be performed within a BSC or other primary barrier system. Equipment that may produce aerosols must be contained in primary barrier devices that exhaust air through HEPA filtration before being discharged into the laboratory. These HEPA filters should be tested annually and replaced as needed. HEPA filtered exhaust air from a Class II BSC can be safely re-circulated into the laboratory environment if the cabinet is tested and certified at least annually and operated according to manufacturer's specifications. 2. Workers must wear laboratory clothing, such as scrub suits, before entering the room used for donning positive pressure suits. All laboratory clothing must be removed in the dirty side change room before entering the personal shower. 3. Inner disposable gloves must be worn to protect against break or tears in the outer suit gloves. Disposable gloves must not be worn outside the change area. Alternatives to latex gloves should be available. Do not wash or reuse disposable gloves. Inner gloves must be removed and discarded in the inner change room prior to entering the personal shower. Dispose of used gloves with other contaminated waste. 4. Decontamination of outer suit gloves is performed during laboratory operations to remove gross contamination and minimize further contamination of the laboratory. D. Laboratory Facilities (Secondary Barriers) Cabinet Laboratory 1. The BSL-4 cabinet laboratory consists of either a separate building or a clearly demarcated and isolated zone within a building. Laboratory doors must have locks in accordance with the institutional policies. Rooms in the facility must be arranged to ensure sequential passage through an inner (dirty) changing area, a personal shower and an outer (clean) change room upon exiting the room(s) containing the Class III BSC(s). An automatically activated emergency power source must be provided at a minimum for the laboratory exhaust system, life support systems, alarms, lighting, entry and exit controls, BSCs, and door gaskets. Monitoring and control systems for air supply, exhaust, life support, alarms, entry and exit controls, and security systems should be on an uninterrupted power supply (UPS). A double-door autoclave, dunk tank, fumigation chamber, or ventilated airlock must be provided at the containment barrier for the passage of materials, supplies, or equipment. 2. A hands-free sink must be provided near the door of the cabinet room(s) and the inner change room. A sink must be provided in the outer change room. All sinks in the room(s) containing the Class III BSC must be connected to the wastewater decontamination system. 3. Walls, floors, and ceilings of the laboratory must be constructed to form a sealed internal shell to facilitate fumigation and prohibit animal and insect intrusion. The internal surfaces of this shell must be resistant to chemicals used for cleaning and decontamination of the area. Floors must be monolithic, sealed and coved. All penetrations in the internal shell of the laboratory and inner change room must be sealed. Openings around doors into the cabinet room and inner change room must be minimized and capable of being sealed to facilitate decontamination. Drains in the laboratory floor (if present) must be connected directly to the liquid waste decontamination system. Services and plumbing that penetrate the laboratory walls, floors, or ceiling must be installed to ensure that no backflow from the laboratory occurs. These penetrations must be fitted with two (in series) backflow prevention devices. Consideration should be given to locating these devices outside of containment. Atmospheric venting systems must be provided with two HEPA filters in series and be sealed up to the second filter. Decontamination of the entire cabinet must be performed using a validated gaseous or vapor method when there have been significant changes in cabinet usage, before major renovations or maintenance shut downs, and in other situations, as determined by risk assessment. Selection of the appropriate materials and methods used for decontamination must be based on the risk assessment. 4. Laboratory furniture must be of simple construction, capable of supporting anticipated loading and uses. Spaces between benches, cabinets, and equipment must be accessible for cleaning and decontamination. Chairs and other furniture must be covered with a non-porous material that can be easily decontaminated. 5. Windows must be break-resistant and sealed. 6. If Class II BSCs are needed in the cabinet laboratory, they must be installed so that fluctuations of the room air supply and exhaust do not interfere with proper operations. Class II cabinets should be located away from doors, heavily traveled laboratory areas, and other possible airflow disruptions. 7. Central vacuum systems are not recommended. If, however, there is a central vacuum system, it must not serve areas outside the cabinet room. Two in-line HEPA filters must be placed near each use point. Filters must be installed to permit in-place decontamination and replacement. 8. An eyewash station must be readily available in the laboratory. 9. A dedicated non-recirculating ventilation system is provided. Only laboratories with the same HVAC requirements (i.e., other BSL-4 labs, ABSL-4, BSL-3-Ag labs) may share ventilation systems if gas-tight dampers and HEPA filters isolate each individual laboratory system. The supply and exhaust components of the ventilation system must be designed to maintain the laboratory at negative pressure to surrounding areas and provide differential pressure or directional airflow, as appropriate, between adjacent areas within the laboratory. Redundant supply fans are recommended. Redundant exhaust fans are required. Supply and exhaust fans must be interlocked to prevent positive pressurization of the laboratory. The ventilation system must be monitored and alarmed to indicate malfunction or deviation from design parameters. A visual monitoring device must be installed near the clean change room so proper differential pressures within the laboratory may be verified prior to entry. Supply air to and exhaust air from the cabinet room, inner change room, and fumigation/decontamination chambers must pass through HEPA filter(s). The air exhaust discharge must be located away from occupied spaces and building air intakes. All HEPA filters should be located as near as practicable to the cabinet and laboratory in order to minimize the length of potentially contaminated ductwork. All HEPA filters must be tested and certified annually. The HEPA filter housings should be designed to allow for in situ decontamination and validation of the filter prior to removal. The design of the HEPA filter housing must have gas-tight isolation dampers, decontamination ports, and ability to scan each filter assembly for leaks. 10. HEPA filtered exhaust air from a Class II BSC can be safely re-circulated into the laboratory environment if the cabinet is tested and certified at least annually and operated according to the manufacturer's recommendations. If BSC exhaust is to be recirculated to the outside, BSCs can also be connected to the laboratory exhaust system by either a thimble (canopy) connection or a hard ducted, direct connection ensuring that cabinet exhaust air passes through two (2) HEPA filters—including the HEPA in the BSC—prior to release outside. Provisions to assure proper safety cabinet performance and air system operation must be verified. Class III BSCs must be directly and independently exhausted through two HEPA filters in series. Supply air must be provided in such a manner that prevents positive pressurization of the cabinet. 11. Pass through dunk tanks, fumigation chambers, or equivalent decontamination methods must be provided so that materials and equipment that cannot be decontaminated in the autoclave can be safely removed from the cabinet room(s). Access to the exit side of the pass-through shall be limited to those individuals authorized to be in the BSL-4 laboratory. 12. Liquid effluents from cabinet room sinks, floor drains, autoclave chambers, and other sources within the cabinet room must be decontaminated by a proven method, preferably heat treatment, before being discharged to the sanitary sewer. Decontamination of all liquid wastes must be documented. The decontamination process for liquid wastes must be validated physically and biologically. Biological validation must be performed annually or more often if required by institutional policy. Effluents from showers and toilets may be discharged to the sanitary sewer without treatment. 13 A double-door, pass through autoclave(s) must be provided for decontaminating materials passing out of the cabinet laboratory. Autoclaves that open outside of the laboratory must be sealed to the interior wall. This bioseal must be durable and airtight and capable of expansion and contraction. Positioning the bioseal so that the equipment can be accessed and maintained from outside the laboratory is strongly recommended. The autoclave doors must be interlocked so that only one can be opened at any time and be automatically controlled so that the outside door to the autoclave can only be opened after the decontamination cycle has been completed. Gas and liquid discharge from the autoclave chamber must be decontaminated. When feasible, autoclave decontamination processes should be designed so that unfiltered air or steam exposed to infectious material cannot be released to the environment. 14. The BSL-4 facility design parameters and operational procedures must be documented. The facility must be tested to verify that the design and operational parameters have been met prior to operation. Facilities must also be re-verified annually. Verification criteria should be modified as necessary by operational experience. 15. Appropriate communication systems must be provided between the laboratory and the outside (e.g., voice, fax, and computer). Provisions for emergency communication and emergency access or egress must be developed and implemented. Suit Laboratory 1. The BSL-4 suit laboratory consists of either a separate building or a clearly demarcated and isolated zone within a building. Laboratory doors must have locks in accordance with the institutional policies. Rooms in the facility must be arranged to ensure exit by sequential passage through the chemical shower, inner (dirty) change room, personal shower, and outer (clean) changing area. Entry into the BSL-4 laboratory must be through an airlock fitted with airtight doors. Personnel who enter this area must wear a positive pressure suit supplied with HEPA filtered breathing air. The breathing air systems must have redundant compressors, failure alarms and emergency backup. A chemical shower must be provided to decontaminate the surface of the positive pressure suit before the worker leaves the laboratory. In the event of an emergency exit or failure of the chemical shower system, a method for decontaminating positive pressure suits, such as a gravity fed supply of chemical disinfectant, is needed. An automatically activated emergency power source must be provided, at a minimum, for the laboratory exhaust system, life support systems, alarms, lighting, entry and exit controls, BSCs, and door gaskets. Monitoring and control systems for air supply, exhaust, life support, alarms, entry and exit controls, and security systems should be on a UPS. A double-door autoclave, dunk tank, or fumigation chamber must be provided at the containment barrier for the passage of materials, supplies, or equipment in or out of the laboratory. 2. Sinks inside the suit laboratory should be placed near procedure areas and be connected to the wastewater decontamination system. 3. Walls, floors, and ceilings of the laboratory must be constructed to form a sealed internal shell to facilitate fumigation and prohibit animal and insect intrusion. The internal surfaces of this shell must be resistant to chemicals used for cleaning and decontamination of the area. Floors must be monolithic, sealed and coved. All penetrations in the internal shell of the laboratory, suit storage room and the inner change room must be sealed. Drains, if present, in the laboratory floor must be connected directly to the liquid waste decontamination system. Sewer vents must have protection against insect and animal intrusion. Services and plumbing that penetrate the laboratory walls, floors, or ceiling must be installed to ensure that no backflow from the laboratory occurs. These penetrations must be fitted with two (in series) backflow prevention devices. Consideration should be given to locating these devices outside of containment. Atmospheric venting systems must be provided with two HEPA filters in series and be sealed up to the second filter. 4. Laboratory furniture must be of simple construction, capable of supporting anticipated loading and uses. Sharp edges and corners should be avoided. Spaces between benches, cabinets, and equipment must be accessible for cleaning and decontamination. Chairs and other furniture must be covered with a non-porous material that can be easily decontaminated. 5. Windows must be break-resistant and sealed. 6. BSCs and other primary containment barrier systems must be installed so that fluctuations of the room air supply and exhaust do not interfere with proper operations. BSCs should be located away from doors, heavily traveled laboratory areas, and other possible airflow disruptions. 7. Central vacuum systems are not recommended. If, however, there is a central vacuum system, it must not serve areas outside the BSL-4 laboratory. Two in-line HEPA filters must be placed near each use point. Filters must be installed to permit in-place decontamination and replacement. 8. An eyewash station must be readily available in the laboratory area for use during maintenance and repair activities. 9. A dedicated, non-recirculating ventilation system is provided. Only laboratories with the same HVAC requirements (i.e., other BSL-4 labs, ABSL-4, BSL-3 Ag labs) may share ventilation systems if gas-tight dampers and HEPA filters isolate each individual laboratory system. The supply and exhaust components of the ventilation system must be designed to maintain the laboratory at negative pressure to surrounding areas and provide differential pressure or directional airflow as appropriate between adjacent areas within the laboratory. Redundant supply fans are recommended. Redundant exhaust fans are required. Supply and exhaust fans must be interlocked to prevent positive pressurization of the laboratory. The ventilation system must be monitored and alarmed to indicate malfunction or deviation from design parameters. A visual monitoring device must be installed near the clean change room so proper differential pressures within the laboratory may be verified prior to entry. Supply air to the laboratory, including the decontamination shower, must pass through a HEPA filter. All exhaust air from the suit laboratory, decontamination shower and fumigation or decontamination chambers must pass through two HEPA filters, in series, before discharge to the outside. The exhaust air discharge must be located away from occupied spaces and air intakes. All HEPA filters must be located as near as practicable to the laboratory in order to minimize the length of potentially contaminated ductwork. All HEPA filters must be tested and certified annually. The HEPA filter housings must be designed to allow for in situ decontamination and validation of the filter prior to removal. The design of the HEPA filter housing must have gas-tight isolation dampers, decontamination ports, and ability to scan each filter assembly for leaks. 10. HEPA filtered exhaust air from a Class II BSC can be safely re-circulated back into the laboratory environment if the cabinet is tested and certified at least annually and operated according to the manufacturer's recommendations. Biological safety cabinets can also be connected to the laboratory exhaust system by either a thimble (canopy) connection or a direct (hard) connection. Provisions to assure proper safety cabinet performance and air system operation must be verified. 11. Pass through dunk tanks, fumigation chambers, or equivalent decontamination methods must be provided so that materials and equipment that cannot be decontaminated in the autoclave can be safely removed from the BSL-4 laboratory. Access to the exit side of the pass-through shall be limited to those individuals authorized to be in the BSL-4 laboratory. 12. Liquid effluents from chemical showers, sinks, floor drains, autoclave chambers, and other sources within the laboratory must be decontaminated by a proven method, preferably heat treatment, before being discharged to the sanitary sewer. Decontamination of all liquid wastes must be documented. The decontamination process for liquid wastes must be validated physically and biologically. Biological validation must be performed annually or more often if required by institutional policy. Effluents from personal body showers and toilets may be discharged to the sanitary sewer without treatment. 13. A double-door, pass through autoclave(s) must be provided for decontaminating materials passing out of the cabinet laboratory. Autoclaves that open outside of the laboratory must be sealed to the interior wall. This bioseal must be durable, airtight, and capable of expansion and contraction. Positioning the bioseal so that the equipment can be accessed and maintained from outside the laboratory is strongly recommended. The autoclave doors must be interlocked so that only one can be opened at any time and be automatically controlled so that the outside door to the autoclave can only be opened after the decontamination cycle has been completed. Gas and liquid discharge from the autoclave chamber must be decontaminated. When feasible, autoclave decontamination processes should be designed so that unfiltered air or steam exposed to infectious material cannot be released to the environment. 14. The BSL-4 facility design parameters and operational procedures must be documented. The facility must be tested to verify th

What disease do Acanthamoeba cause?

Several species of Acanthamoeba also cause a serious encephalitis that is almost always fatal. It is called granulomatous amebic encephalitis (GAE).

How have Biosafety Levels 1-4 been used since the early 1980's?

Since the early 1980's, laboratories have applied the guidelines to activities involving the human immunodeficiency virus (HIV).

How can Viruses enter through the Skin?

Skin - Intact skin is a strong barrier against viral infection. However, if there are openings as a result of insect or animal bites, or from a cut or scrape, viruses can gain access to the host by this route.

How can Condensation in Hot, Humid Environments be controlled?

Some of the control measures employed to reduce moisture in air-conditioned buildings in hot, humid environments are the opposite of those used in cold climates. Some areas experience both extremes: cold winters and hot, humid summers.

How are Antibiotics used as a Mycotoxin?

Some of these secondary compounds are toxic to bacteria and are called antibiotics. Penicillin is an example.

Where can Sources of Microorganisms that Affect Building Air Quality be Found?

Sources of microorganisms that affect building air quality may be found: 1) outside the building 2) in attics, crawl spaces, and other below grade spaces 3) inside wall cavities 4) in HVAC systems 5) in the occupied spaces.

What disease do Sporobolomyces Fungi cause? What are the sources?

Sporobolomyces fungi cause Hypersensitivity Pneumonitis (HP). Human exposure results from inhaled spores from damp organic material; and standing water.

What disease does Stachybotrys atra cause? What are the sources?

Stachybotrys atra causes Acute Toxicosis. Human exposure results from inhaled Toxins (mycotoxins) from damp cellulosic material.

How have standards for Safety in Microbiology Laboratories changed?

Standards for safety in microbiology laboratories are now developed and accepted for practice. They are based on Biosafety Levels 1-4.

What is sterigmatocystin?

Sterigmatocystin is a toxic metabolite structurally closely related to the aflatoxins, and consists of a xanthone nucleus attached to a bifuran structure. Sterigmatocystin is mainly produced by the fungi Aspergillus nidulans and A. versicolor. It has been reported in mouldy grain, green coffee beans and cheese although information on its occurrence in foods is limited. It appears to occur much less frequently than the aflatoxins, although analytical methods for its determination have not been as sensitive until recently, and so it is possible that small concentrations in food commodities may not always have been detected. Although it is a potent liver carcinogen similar to aflatoxin B1, current knowledge suggests that it is nowhere near as widespread in its occurrence. If this is the true situation it would be justified to consider sterigmatocystin as no more than a risk to consumers in special or unusual circumstances. A number of closely related compounds such as o-methyl sterigmatocystin are known, and some may also occur naturally. The toxic effects of sterigmatocystin are much the same as those of aflatoxin B1. It is thus considered as a potent carcinogen, mutagen, and teratogen. It is less acutely toxic to rodents and monkeys but appears to be slightly more toxic to zebra fish. The LD50 in mice is in excess of 800 mg/kg. The 10-day LD50 in Wistar rats is 166 mg/kg in males, 120 mg/kg in females, and 60-65 mg/kg for ip. administration in males. The ip. 10-day LD50 for vervet monkeys is 32 mg/kg. Chronic symptoms include induction of hepatomas in rats, pulmonary tumours in mice, renal lesions and alterations in the liver and kidneys of African Green monkeys. Rats fed 5-10 mg/kg of sterigmatocystin for two years showed a 90% incidence of liver tumours. It has been suggested that sterigmatocystin is about 1/10 as potent a carcinogen as aflatoxin B1. Toxic effects of sterigmatocystin-fed laboratory animals have included kidney and liver damage and diarrhoea. Skin and hepatic tumours are induced in rats by dermal application. Cattle exhibiting bloody diarrhoea, loss of milk production and in some cases death were found to have ingested feed containing Aspergillus versicolor and high levels of sterigmatocystin of about 8 mg/kg. The acute toxicity, carcinogenicity, and metabolism of sterigmatocystin has been compared with those for aflatoxin and several other hepatotoxic mycotoxins. The IARC-classification of sterigmatocystin is group 2B, which means it is carcinogenic in other species and is possibly carcinogenic to humans, but that a definitive link between human exposure and cancer has not been proven.

What are Hypersensitivity Diseases?

Subsequent exposures produce a greater effect.

How can you control available Nutrients in order to prevent Microbial Growth in Buildings?

Suitable nutrients for microorganisms are found in gypsum board, wood paneling, cellulose based products such as ceiling tiles, carpets, upholstered furnishings, accumulations of dust, and acoustic linings in ventilation ducts.

How can Superficial Fungal Infections be hazardous?

Superficial fungal infections of the skin, nails, hair, and mucous membranes are more common. Dermatophytic fungi use keratin as a nutrient source.

Historically, what types of Biohazards have Laboratory personnel encountered?

Surveys conducted periodically over the years since 1949 provide information regarding the number of laboratory-associated infections, the source of infections, the diseases or infections contracted, the number of fatalities, and the suspected causes of infection or disease.

What are symptoms of Allergies?

Symptoms are often localized to the contact area. For example, the response to airborne allergens such as ragweed is in the respiratory system. Generalized allergic responses may also occur.

How do Bacteria cause Humidifier Fever?

Symptoms usually become evident within 4 to 8 hours following exposure and are gone within 24 hours, without lasting effects.

How does Temperature affect Fungal growth?

Temperature affects fungal growth but is not usually limiting. Some fungi grows well at 4° C. (This is demonstrated regularly in refrigerators everywhere!)

What disease does the Adenovirus cause? Where are symptoms produced?

The Adenovirus produces Rhinitis, Pharyngitis, and the Common Cold. Symptom site: Upper Respiratory Tract.

What disease does the Coronavirus cause? Where are symptoms produced?

The Coronavirus produces Rhinitis, Pharyngitis, and the Common Cold. Symptom site: Upper Respiratory Tract.

What disease does the Enterovirus cause? Where are symptoms produced?

The Enterovirus produces Rhinitis, Pharyngitis, and the Common Cold. Symptom site: Upper Respiratory Tract.

What disease does the Hantavirus cause? Where are symptoms produced?

The Hantavirus produces Hantavirus Pulmonary Syndrome. Symptom site: Middle and Lower Respiratory Tract.

What disease does the Influenza Virus cause? Where are symptoms produced?

The Influenza Virus produces Tracheitis, Bronchitis, and Pneumonia. Symptom site: Middle and Lower Respiratory Tract.

Who has developed and adopted Universal Precautions?

The Laboratory Centre for Disease Control, Health Canada, and the U.S. Centers for Disease Control have developed and adopted Universal Precautions.

What disease does the Measles Virus cause? Where are symptoms produced?

The Measles Virus produces Rubeola (Measles), Encephalomyelitis, Viral Meningitis. Symptom site: Skin and Central Nervous System.

What disease does the Mumps Virus cause? Where are symptoms produced?

The Mumps Virus produces Encephalomyelitis, Viral Meningitis, and Infectious Parotitis (mumps). Symptom site: Central Nervous System and Salivary Glands.

What disease does the Parainfluenza Virus cause? Where are symptoms produced?

The Parainfluenza Virus produces Tracheitis, Bronchitis, Pneumonia, Rhinitis, Pharyngitis, and the Common Cold. Symptom site: Middle and Lower Respiratory Tract, Upper Respiratory Tract.

What disease does the Respiratory Syncytial Virus cause? Where are symptoms produced?

The Respiratory Syncytial Virus produces Tracheitis, Bronchitis, and Pneumonia. Symptom site: Middle and Lower Respiratory Tract.

What disease does the Rhinovirus cause? Where are symptoms produced?

The Rhinovirus produces Rhinitis, Pharyngitis, and the Common Cold. Symptom site: Upper Respiratory Tract.

What disease does the Rubella Virus cause? Where are symptoms produced?

The Rubella Virus produces Rubella (German measles). Symptom site: Skin.

What disease does the Varicella-zoster Virus cause? Where are symptoms produced?

The Varicella-zoster Virus produces Chicken Pox and Shingles. Symptom site: Skin.

Can Antibiotics be used to treat Viral Infections?

The antibiotics used to treat bacterial infections do not work with viral infections. Sometimes antibiotics are used during viral infections to treat secondary bacterial infections.

What Defenses are present if Microorganisms gain entry into the Body?

The body fights infection by forming antibodies, the action of complement, and the activities of phagocytic cells. These processes are interrelated.

Why is it important to control Relative Humidity, Temperature and Condensation when attempting to prevent Moisture production?

The control of relative humidity and surface temperatures are important for comfort and for minimizing microbial growth. Relative humidity should not exceed 60%.

How have standards for Safety in Microbiology Laboratories changed?

The document "Biosafety in Microbiological and Biomedical Laboratories" may be referenced for descriptions of the four levels and associated control measures.

What Environmental Factors affect the distribution of Fungi?

The environmental factors that affect the distribution of fungi include 1) water 2) nutrients 3) temperature 4) light.

What is the First Line of Defense against Microorganisms?

The first line of defense against micro-organisms is the complex barriers provided by external and internal body surfaces. The skin, with its thick layers of cells and secretions, is almost impervious to micro-organisms.

Sample Checklist for Investigating Air Quality (conducted after walkthrough survey)

The following checklist template may be useful for developing a site specific checklist to identify potential microbial sources in and around a building:

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Drain Pans?

The following measures should be undertaken to prevent this from occurring: 1) Slope pans to drain completely. A drop of 0.2 cm per 10 cm of pan length is optimum. The slope should direct water towards the drain. 2) Install a water trap in the drain line. 3) Keep drain pans clean. If microbial growth occurs, physically remove it. Do not use a biocide treatment without first removing the growth.

What measures can be taken to prevent Fungi growth following flooding or water leaking in a Building?

The following measures should help to limit growth in wetted materials. 1) Drying the materials thoroughly within one to two days. 2) Discard sewage contaminated porous materials. 3) Repair structures as necessary to prevent future water infiltration.

What procedures can be used for Laundry workers in Hospitals?

The following procedures may be used as a guide to prevent exposure: 1) Place linen in plastic bags at the bedside instead of carrying it through the halls to collection bags. 2) Colour code laundry bags to alert employees to potential hazards.

Infectious Diseases and Associated "at risk" Occupations Table

The following table gives examples of infectious diseases and occupational settings where they may be contracted:

What is the purpose of using Biocides in Mould Remediation?

The goal of remedial measures is to remove all microbial growth. This can usually be accomplished by physically removing materials that support growth, or by thorough cleaning of non-porous surfaces with a detergent or cleaning solution.

What is the purpose of the Guidelines for the Assessment and Remediation of Fungi in Indoor Environments?

The guidelines are applicable to all types of fungal contamination, and the concepts would be of value when facing a clean-up project involving many types of microbial contamination. The guidelines include clean-up and removal procedures for six levels of fungal contamination.

How do Agricultural workers get exposed to Zoonoses?

The infectious agents gain entry into the body by inhalation, ingestion, or through the skin or mucous membranes.

Who should the Investigation Team be made up of?

The investigation team should be made up of management and maintenance personnel, and at least one person who is familiar with the sources and signs of microbial contamination.

What is the purpose of the Guidelines for the Assessment and Remediation of Fungi in Indoor Environments?

The levels are based on location and extent of contamination. Before beginning any microbial remediation project, the full guidelines found in this link should be referenced.

What is the purpose of conducting a Walkthrough Inspection?

The main purposes of the walkthrough inspection are to collect general information about the area of concern and determine if there is a need for a more in-depth study, which may involve various types of sampling.

What does the outcome of the Host-Parasite Relationship depend on?

The outcome of the host-parasite relationship depends on: 1) the virulence of the parasite 2) health and resistance of the host.

What procedures can be used for Nursing workers in Hospitals?

The precautionary measures including protective clothing, hand washing, and attention to proper work procedures that have been described in previous sections are applicable to nurses.

What is the Primary Transmission route of Hospital Acquired Infections?

The primary transmission route of hospital acquired infections is personal contact. Potential biological hazards exist in most hospital departments.

How have Biosafety Levels 1-4 been used since the early 1980's?

The principles for handling a bloodborne pathogen were suitable for safe laboratory work even before HIV was identified as the causative agent of acquired immunodeficiency virus (AIDS).

What is the purpose of using Personal Protective Equipment when exposed to blood and certain body fluids?

The purpose of PPE is to prevent blood and body fluids from reaching the workers' skin, mucous membranes, or personal clothing.

What is the purpose of the Guidelines for the Assessment and Remediation of Fungi in Indoor Environments?

The table below is a summary of the "Guidelines on Assessment and Remediations of Fungi in Indoor Environments", which was developed by the New York City Department of Health.

Toxic property of mycotoxins in fungi common to house dust

The table below shows some of the toxic properties of mycotoxins common to house dust. Mycotoxin (fungal species)

What are Bioaerosols?

The term "bioaerosol" refers to airborne particles composed of or derived from living organisms. Included in the group are whole organisms, fragments, toxins, and particulate waste products from all varieties of living things, including bacteria, fungi, plants, and animals.

What is a Parasite?

The term "parasite" generally refers to a plant or animal organism. It lives in or on another organism from which it derives an advantage such as nourishment, but does not reciprocate. The relationship does not necessarily cause harm or disease to the host organism.

How can Prevention and Cleaning Management be used to control Microbial Growth?

The three basic elements of a long-term plan to maintain building performance and prevent microbial contamination are: 1) Routine inspections and immediate response to problems and complaints. 2) Preventive maintenance of the building structure, the HVAC system, and the plumbing system. 3) Good housekeeping practices.

How can Remedial Measures be used to control Microbial Growth?

The three basic stages of remediation are: 1) Removal of porous materials showing extensive microbial growth. 2) Physical removal of surface microbial growth on non-porous materials. 3) Reduction of moisture to levels that will not support microbial growth. (To access the United States Environmental Protection Agencies (EPA) websites' information on Mold Remediation in Schools and Commercial Buildings https://www.epa.gov/mold)

How do Fungi cause Toxicity?

The toxic effects of exposure to fungi may be caused by exposure to: 1) the fungus itself 2) its associated volatile organic compounds 3) mycotoxins.

How can Condensation in Building Envelops be controlled using Vapour Barriers (in Cold Climates)?

The vapour barrier is also located on the warm side of the building envelope, between the insulation and the air barrier, if there is one. It also prevents penetration of water into the building envelope.

How do Viruses exert their toxic effects?

The virus particle is an inert form of the virus. When it interacts with a suitable host cell, a virus-cell complex is formed. There are two common interactions: 1) A "lytic" interaction that results in destruction (lysis) of the host cell. 2) Integration of the viral genetic material into the host cell DNA, which could result in transformation of the host cell, some changes to the host cell, or no changes to it.

Why are Antiviral Chemotherapeutic drugs not always successful at treating Viral Infections?

There are antiviral chemotherapeutic drugs that work by blocking stages of the virus replication cycle. Although they work well in the laboratory, they are not commonly used for people, either because they do not halt virus replication or because of the toxic side effects.

Where are Fungi found? Why are swab cultures not good indicators of environmental contamination?

There are few places on earth that are fungus free. Even dry environmental surfaces are not sterile, unless they have been intentionally sterilized. For this reason, swab cultures of surfaces are meaningless on their own as indicators of environmental contamination.

What are the classes of Biocides?

There are many biocide classes. They include 1) alcohols 2) aldehydes 3) halogens (e.g. chlorine, bromine, iodine) 4) hydrogen peroxide 5) phenolic compounds 6) quaternary ammonium compounds.

What are the 3 main classes of viruses?

There are three main classes of viruses: 1) Animal viruses 2) Plant viruses 3) Bacterial viruses

What are the two basic types of Humidifiers?

There are two basic types of humidifiers. One emits droplets or spray from a water reservoir. It is more prone to microbial contamination and dissemination of bioaerosols. The other injects steam into the supply air. Steam injection systems are generally safer and easier to maintain.

How do Fungi produce Hypersensitivity Diseases?

There is also evidence that indicates that sensitization and exposure to fungi increases the chances that an asthma attack will be fatal. HP may also result from exposure to fungi.

How are Biological Hazards classified?

There is more than one system for classifying life forms. The table below shows the major kingdoms used by some biologists to classify living organisms. The table is adapted from "Bioaerosols: Assessment and Control", an ACGIH publication. It describes characteristics and sources of common bioaerosols.

How can Amoeba be harmful to Humans?

These are not normally a concern in indoor air. Naegleria and Acanthamoeba are free-living amoebae that can be transmitted by air, be inhaled, and cause infectious disease or inhalation fever.

How can Condensation in Hot, Humid Environments be controlled using Air Barriers and Vapour Barriers?

These should be located on the outer portion of the building envelope.

What are Viruses?

They are completely dependent on their host for reproduction. Viruses are the smallest organism that we know of, much smaller than bacteria, rickettsia, or chlamydia.

How do Fungi cause disease?

They are made up of hyphae, which can grow to penetrate skin or the surface of plants -the tissue damage associated with fungal infections results primarily from direct invasion of tissue, with subsequent displacement and destruction of vital structures, coupled with toxic effects of the inflammatory response -masses of fungal cells can cause obstruction of bronchi in the lungs and tubules and ureters in kidneys, leading to obstruction of the flow of bodily fluids -some fungi can grow in the walls of arteries and veins, leading to occlusion and tissue necrosis resulting from a lack of oxygen

Where are House Dust Mites found?

They are most prevalent in high-use areas such as living rooms, bedrooms, and areas with carpet and upholstered furniture. Human skin scales and animal dander are primary food sources for dust mites. The skin one person sheds each day could feed several thousand mites for up to three months.

What are Fungi?

They are parasitic or saprophytic, or both. Saprophytic organisms use dead organic material for food. Some types of fungi are symbiotic, meaning they grow in close association with another living organism and both benefit from the association.

What are Antimicrobial Agents?

They bind with the fibres or material surfaces that they are applied to. The binding allows the antimicrobial agent to inhibit or prevent the growth of bacteria or fungi that come into contact with the treated surface.

When do Universal Precautions not apply?

They do not apply to feces, nasal secretions, sputum, sweat, tears, urine, vomitus, or saliva (except in dental settings where saliva may be contaminated with blood).

How do Saprophitic Microorganisms generate reservoirs of Bioaerosols?

They live in environmental reservoirs, such as non-living plant materials, and are amplified and disseminated either from these reservoirs or from indoor substrates.

How do Agricultural workers get exposed to Zoonoses?

They may also be transmitted indirectly by inhalation of spore-laden dusts. Mosquitoes, flies, fleas, and other insect vectors may also help to transmit zoonoses dwell in garbage, water, or milk.

What are Bacteria?

They multiple by simple division or fission into two parts.(microscopic single-celled organisms that have the capability of reproducing on their own without a host. Typically respond to antibiotics)

How can you control Condensation in Cold Climates?

This is often seen as dark spots on walls in corners, around windows, and behind furniture.

What are the objectives of this module?

This module was designed to familiarize you with biological hazards. After completing it, you should be able to: Define "biohazard" and "bioaerosol" List and explain the main classes of biological hazardous agents Identify potential exposures in the workplace Recognize "at risk" occupations Detect building materials and furnishings that may be contaminated Design a checklist for inspecting the workplace or home Recommend appropriate controls or remedial measures when there is contamination

What risks are present for workers who work in Biological Research Laboratories?

Those who work in biological research laboratories obviously face a potential risk of exposure to biohazardous materials. Microbiology laboratories are unique work environments that may present identifiable infectious disease risks to anyone who works in or near them.

What are Rickettsia?

Ticks present a problem for outdoor workers in wooded areas. The initial bite is painless. The worker may not notice the tick until several days later when the itching indicates its presence.

What is a Critical Barrier?

Two layers of heavy duty polyethylene sheeting are used as critical barriers to separate the clean or occupied building area from the contaminated area.

What symptoms do Ulocladium Fungi cause? What are the sources?

Ulocladium fungi cause Headache. Human exposure results from inhaled VOCs from damp organic material.

How can you control Condensation in Cold Climates?

Unfortunately, when warm moist air comes into contact with cold surfaces, water condenses out of the air and collects on surfaces. Walls may be cool due to a compromised building envelope.

What are Universal Precautions?

Universal precautions are guidelines for infection control. They are designed to protect workers from exposure to diseases spread by blood and body fluids. With universal precautions, every patient is assumed to be infectious for blood-borne diseases like AIDS and hepatitis B.

When must Universal Precautions be applied?

Universal precautions should be applied in any workplace where workers are exposed to blood and other body fluids including semen, vaginal secretions, and synovial, cerebrospinal, pleural, peritoneal, pericardial, and amniotic fluid.

What is Interferon?

Unlike antibodies, interferon is not specific. All viruses stimulate the production of the same interferon and interferon inhibits the growth and reproduction of many different viruses.

How do Human Sources generate Bacteria?

Upper respiratory viral and bacterial infections like mumps and whooping cough are droplet-borne. Influenza is also thought to be transmitted by the airborne route. Humidifiers or any equipment that generates water spray may introduce bacteria into the air, particularly if recirculated or stagnant water is used.

How can Viruses enter through the Urogenital Tract?

Urogenital tract - Viruses that cause venereal disease enter the body by this route. Herpes simplex is an example.

What factors should be considered when selecting a Biocide?

Using the correct biocide is therefore essential. Three factors are important to consider when selecting a biocide: The type and extent of microbial contamination - What are the active ingredients? What does the manufacturer claim that it will be effective against? Susceptability for the particular application - Is it compatible with the surfaces and materials it will be applied to? Is it inactivated by organic matter? What are the optimum conditions of use (temperature, humidity)? What is the required contact time? Hazards - What are the health and safety hazards? What are the protective equipment and clothing requirements? What are the environmental impacts?

How do Outdoor Environments act as sources of Bacteria?

Usually bacteria from naturally occurring plant life does not cause human illness. The bacteria that causes Legionnaires' disease reside in natural waters and soils.

What types of Vaccinations exist for Viruses?

Vaccinations are available for use in a variety of hosts, including people, to prevent virus infections from occurring. There are vaccines available for prevention of polio, influenza, rabies, measles, mumps, hepatitis, and arboviruses.

How can Porous Materials be used to control Microbial Growth?

Valuable books and papers are sometimes salvageable by fumigation, freeze-drying, and vacuum removal of particles.

What are Viruses?

Viruses are non-cellular, parasitic pathogens. They are basically nucleic acid cores in a protein coat. They do not have the ability to produce energy or make protein, and are obligate parasites, which means they cannot live without a living host.

What are Viruses?

Viruses are not easily classifiable among living organisms, because they are not really alive, except in association with a living cell.

How are Viruses able to Infect Cells?

Viruses change and adapt to changes in the environment. For example, the influenza virus regularly changes its antigenic makeup. There is evidence that this is also the case for the Human Immunodeficiency Virus (HIV), the blood-borne virus that causes Acquired Immune Deficiency Syndrome (AIDS).

What routes of entry can Viruses enter through?

Viruses may enter the host by contact with the eyes, the genitals or damaged skin, or by inhalation or ingestion.

Why is Water important for Fungi?

Water is the most important factor that controls fungal growth. Mycologists discuss water availability in terms of "water activity" or aw. It is a measure of the water in a substrate that can be used by the fungus for growth.

What is the most important factor that controls Fungal Growth?

Water or moisture

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Humidifiers?

Water spray humidifiers and air washers are not recommended because they require frequent maintenance to prevent microbial growth.

What disease can Naegleria Amoeba cause?

Waterborne amoebae enter through the nasal passages, and travel to the olfactory lobes and cerebral cortex. The infection results in high fever, severe headache, strange behavior, and usually death.

How do Viruses cause disease?

When a virus successfully invades the host, the damage may be undetected, mild, severe, fatal, teratogenic, behavioral, or it could result in the formation of tumors. The virus is not an active poison in the body. When severe cell damage occurs as a result of a viral infection, it is the immune response of the host that causes the damage.

How can Moisture in Heating, Ventilating, and Air Conditioning (HVAC) System Components be controlled by maintaining Cooling Coils?

When air is moved through cooling coils too quickly, the coils cannot remove the moisture from it. This can be a problem because droplets will then be deposited on the insides of ducts downstream from the coils.

How can Remedial Measures be used to control Microbial Growth?

When control measures have failed and there is visible microbial growth in a building, remedial measures must be undertaken using a recognized remediation protocol.

What disease do Acanthamoeba cause?

When it contacts the eyes, Acanthamoeba can cause serious infections which can be treated with antibiotics.

What Defenses are present if Microorganisms gain entry into the Body?

When micro-organisms do gain access to the body, they may multiply and produce toxins. The affected person usually notices the symptoms of infection.

During an Allergic Reaction, what happens if Histamine is released?

Widespread release of histamine may produce hives, extensive skin eruptions, bronchospasm, rapid heart rate, and hypotension. In extreme cases, death may occur from a single exposure. For example, without prompt medical attention a person who is allergic to bee stings could die from a single sting.

How are Viruses able to Infect Cells?

Within each class, a particular virus is usually able to infect only a certain species of cells, although some viruses are able to infect cells of several species, for example humans and another animal, or kidney and liver cells.

How do workers who work with animals get exposed to Anthrax?

Workers who handle animal products may be at risk of cutaneous anthrax. The most common cause is imported animal hair and raw wool contaminated with anthrax spores.

A plan for resolving and controlling problems related to microbial growth in buildings consists of ______________? a) Removing and cleaning contaminated materials and areas, and correcting the source b) Upon discovery, and frequently thereafter, thoroughly washing all affected areas with a 2% Tri-sodium Phosphate solution c) Establish clear corporate policies to ensure exposures to microbes are within established TLV's d) Identify those with sensitivities to identified microbes, and provide alternate employment in unaffected areas

a

Anthrax is an occupational disease most commonly found in _________________ workers. a) Animal handlers b) Active military personnel c) Postal workers d) Truckers

a

Hypersensitivity diseases are caused by exposure to antigens, such as bacteria, fungi and amoebae. Hypersensitivity pneumonitis (HP) is an example of a hypersensitivity disease. What are the symptoms of HP? a) Recurrent pneumonia with fever, cough, and chest tightness b) High fever, severe headache, strange behavior, and death c) Raised, red rash, with itching and burning d) Flu-like symptoms - fever, chills, muscle aches, malaise, and chest symptoms

a

What health effects are associated with exposure to endotoxins? a) Help stimulate the immune system at low concentrations. b) Can produce flu-like symptoms at low concentrations. c) Cause Legionnaires' disease. d) Can cause reproductive effects.

a

What is the body's first line of defense against microorganisms? a) Body surfaces including skin and mucous membranes b) Phagocytes c) Antibodies d) Mucociliary escalator

a

Appropriate remedial measures for treatment of cellulose ceiling tiles that have been subject to chronic leaks are as follows: a) Clean the tiles with a sodium hypochlorite solution and dry thoroughly b) Remove and discard them c) Treat the tiles with an antimicrobial agent d) Vacuum the tiles with a HEPA vacuum cleaner and paint the surfaces with an antimicrobial paint.

b

During a walkthrough inspection, the investigator concentrates on what? a) Doing sampling to measure airborne microbial concentrations. b) Collecting information about the area of concern and determining if there is a need for a more in-depth study c) Conducting a thorough building analysis d) Passing through an intact wall and coming out on the other side unscathed.

b

Free-living amoebae are found in soil, water, and on vegetation. They have been identified in home humidifiers, in swimming pools, and in industrial process fluids. What are the associated potential health effects? a) A rare form of brain inflammation, as a result of exposure to Rickettsia. b) Humidifier fever c) Anthrax d) Tuberculosis

b

Histoplasmosis is a hypersensitivity disease caused by exposure to fungi. What is the usual source of the fungi? a) Damp, mouldy hay. b) Bird droppings c) Cheese d) Ticks

b

The primary transmission route of hospital acquired infections is _______. a) Inadequate sterilization of instruments b) Personal contact c) Air quality d) Housekeeping failures

b

What are mycotoxins? a) Mycotoxins comprise the outer spore membrane of bacteria b) Chemical compounds produced during the fungal digestion process c) A chemical substance in the cell walls of fungi d) Volatile organic compounds

b

What is the most important thing to do for humidifier drain pans to prevent microbial growth in an HVAC system? a) Treat them regularly with a suitable biocide. b) Ensure they are sloped to drain properly c) Proper placement of the supply air fan immediately upstream d) Install a steam injection system

b

____________________ humidifier systems are generally safer and easier to maintain than others. a) Centrifugal b) Steam injection c) Evaporative tape d) Condensor

b

Bacteria from naturally occurring plant life is _______________ : a) Often dangerous at relatively low concentrations b) Responsible for 'correcting' human immune system imbalances c) Usually not harmful to health d) Typically a problem in work environments with no or little natural vegetation

c

What is an example of a viral infection? a) Legionnaires disease b) Organic dust toxic syndrome c) Rubella d) Pontiac fever

c

What is the difference between a biohazard and a bioaerosol? a) A biohazard is an infectious agent and a bioaerosol is airborne. b) A biohazard affects the well-being of people and animals and a bioaerosol affects only people. c) Biohazards and bioaerosols are both composed of or derived from living organisms, but bioaerosols are always airborne and are not necessarily a potent hazard to health and well-being. d) Biohazards and bioaerosols are both harmful to the health and well-being of humans and other animals, but bioaerosols are airborne.

c

___________________________ are designed to protect health care workers from exposure to diseases spread by blood and body fluids. a) Risk assessments b) PPE c) Universal precautions d) Fume hoods

c

A microorganism that produces or is capable of producing disease is known as ______. a) Parenthetic b) Para-alveolic c) Pendotoxic d) Pathogenic

d

Diptheria is a contageous disease contracted primarily in the following occupational setting: a) Agricultural b) Mining and earthwork c) Fisheries d) Anywhere

d

What is the most important environmental factor that affects fungal growth? a) Light b) Temperature c) Nutrient source d) Moisture

d

What is the smallest known organism? a) Bacteria b) Rickettsia c) Chlamydia d) Viruses

d

Which of the following is not a route of entry into the body for viruses? a) Inhalation b) Eyes c) Gut d) Intact skin

d

What is Hypersensitivity Pneumonitis?

inflammation of the lung parenchyma caused by antigen exposure. acute episodes present with cough, breathlessness, fever, and malaise that occur with 4-6hrs of antigenic exposure chronic exposure may cause weight loss, clubbing, and honeycombing of the lung. TX: avoid responsible antigen (i.e. birds) Mixed type III/IV hypersensitivity reaction to environmental antigen Signs: dyspnea, cough, chest tightness, headache Seen in farmers or those exposed to birds granulomatous reaction to inhaled organic antigens (ex: pigeon breeder's lung)

What is ochratoxin?

• Common sources include barley and wheat infected with the mold • Human and animal health significance • Immunosuppressive • Carcinogenic • Nephratoxic: causes nephritis in pigs ○ Nephritis - kidney inflammation Ochratoxins are a group of mycotoxins produced by some Aspergillus species (mainly A. ochraceus and A. carbonarius, but also by 33% of A. niger industrial strains) and some Penicillium species, especially P. verrucosum . Ochratoxin A is the most prevalent and relevant fungal toxin of this group, while ochratoxins B and C are of lesser importance. Ochratoxin A is known to occur in commodities such as cereals, coffee, dried fruit, and red wine. It is possibly a human carcinogen and is of special interest as it can be accumulated in the meat of animals. Thus, meat and meat products can be contaminated with this toxin. Exposure to ochratoxins through diet can cause acute toxicity in mammalian kidneys.