Hazard Control and Loss Prevention - Evaluate Risks

When is the highest incidence of sharp object injuries from medical devices? A.During use B.Before use C.During disposal D.After use, but before disposal

The correct answer is D The highest incidence of sharp object injuries from medical devices occurs after use, but prior to disposal. This is the most dangerous time since the sharp object is contaminated with potentially infectious bloodborne agents.

Employers that have employees who volunteer to wear respirators must comply with which of the following provisions in the respiratory protection standard? A.Written respiratory protection program B.Medical examination C.Respirator cleaning/maintenance procedures D.All of the above

The correct answer is: The written program need only cover the specific items pertinent to voluntary respirator use (medical monitoring, cleaning/maintenance procedures, et.al.). 29 CFR 1910.134 (c)(2)

A man is standing on an elevated scaffold measuring 18 ft from the top of the scaffold to the floor. The wheels of the scaffold are locked. The scaffold is 6 ft wide at the base. The height from the ceiling of the building to the floor is 24 ft. The man weighs 200 lbs. The scaffold weighs 400 lbs. The man is pushing on a bar joist at the roof to move the scaffold. What force did the man exert to upset the scaffold? A.50 lbs. B.75 lbs. C.100 lbs. D.150 lbs.

The correct answer is: B Sketch the problem. The scaffold will be upset at the point when the moment resulting from the man pushing on the joist is equal to the moment resulting from the weight of the scaffold plus the weight of the man. Assume the man is standing in the center of the scaffold platform. The total force that will be required to overturn the scaffold is equal to the 400 pounds of the scaffold plus the 200 pounds of the man multiplied by the 3 foot distance that the combined load center is from the edge of the bottom of the scaffold. (Moment = Force * Distance) The man is pushing against the bar joist a total distance of 24 feet from the point of contact between the scaffold and the floor. Therefore, the force that the man must exert to upset the scaffold is equivalent to the Moment divided by the Distance. The resultant equation is F1D1 = F2D2, from the OHST/CHST Examination Reference Handout. F1 equals the force of the man pushing D1 equals the distance to the floor F2 equals the weight of the scaffold plus the weight of the man D2 equals the distance from the center of the scaffold to the edge (F1)(24) = (600)(3) F1 = 1800/24 F1 = 75 lbs

Which of the following are symptoms of hypothermia? A.Numbness and tingling in fingers B.Frozen body parts C.Shaking, rigid muscles, low blood pressure D.Increased body core temperature, convulsions

The correct answer is: C Hypothermia results from prolonged exposure to cold temperatures, characterized by the symptoms listed in Answer C. The symptoms of Raynaud's Phenomenon are numbness and tingling in fingers from exposure to vibration and cold. Frozen body parts are symptoms of frost bite. Increased body core temperatures and convulsions are symptoms of heat stroke.

Excessive exposure to UV radiation for a short period of time can cause: A.Welder's flash B.Stoker's problem C.Hypothermia D.Pyrogenic response

The correct answer is: A Acute UV exposure can cause a characteristic eye condition called welder's flash. It is characterized by a gritty feeling in the eye and excessive tears. It is a temporary condition and rarely causes permanent damage.

Which of the following is mostly an internal hazard? A.Alpha particles B.Beta particles C.Gamma radiation D.Protons

The correct answer is: A Alpha particles travel only a few centimeters in air and up to 60 micrometers in human tissue. Energy is transferred quickly. Skin stops most alpha particles. Therefore, if inhaled or ingested, the damage to internal organs and tissues is of primary importance. The other radiation types can more easily penetrate the body from external sources.

Byssinosis is an occupational disease related to the exposure of: A.Cotton fiber dust B.Droppings of infected cattle C.Rickettsial organism D.Fumes of metals

The correct answer is: A Byssinosis is a disease occurring in those persons who experience prolonged exposure to heavy air concentrations of cotton or flax dust.

Rooms in which Class IIIb lasers are used must be labeled and have a warning sign posted on the door. Employees/visitors must wear approved protective eyewear, and interlocks must be installed. A.True B.False C.Depends upon the laser power output D.Additional information is needed

The correct answer is: A Class IIIb lasers can cause permanent eye damage from direct exposure or direct reflections. Entry ways to the laser room must be labeled with approved signs, have an activation key, and be interlocked with the laser. 21 CFR 1040.10 (f) and (g)

All of the following are proteins EXCEPT: A.Hydrocortisone B.Collagen C.Hemoglobin D.Keratin

The correct answer is: A Hydrocortisone is a hormone, generated by the adrenal cortex. Keratin is a skin/hair protein, collagen is a connective tissue protein, and hemoglobin is a blood protein.

Skin absorption causing potentially fatal systemic effects is a hazard associated with exposure to: A.HCN B.CO C.SO2 D.CCl4

The correct answer is: A Hydrogen cyanide (HCN) can be absorbed through the skin and cause cellular asphyxiation by blocking use of oxygen in the cells. CO, SO2, and CCl4 are not systemic poisons by the skin absorption route.

If an employee dons an SCBA for use in a confined space with an IDLH atmosphere, the employee must: A.Don a safety harness/lifeline B.Have a standby worker with a canister respirator C.Have an escape pack D.Not go into the area

The correct answer is: A In the event of an emergency, a safety harness and lifeline is the means of quickly removing the person from the hazardous atmosphere. 29 CFR 1910.146

What type of respiratory protection is required for Level C protection? A.NIOSH-approved full or half-face air-purifying respirator B.NIOSH-approved full face air-purifying respirator only C.NIOSH-approved SCBA D.NIOSH-approved SAR

The correct answer is: A Level C protection includes a full-face or half-face air-purifying respirator. 29 CFR 1910.120 Appendix B

Neutrons cause biological effects through: A.Ions and gamma radiation B.Fission C.Fusion with alpha particles D.X-ray formation from collisions

The correct answer is: A Neutrons cause biological damage from collisions with nuclei that produce ions and gamma radiation. Neutrons are involved in fission in nuclear reactors.

Phosgene primarily produces which of the following physiological effects? A.Mucous membrane, skin, lung, and eye irritation B.Liver and kidney damage C.Narcotic effect D.Both A and B

The correct answer is: A Phosgene is primarily a skin, respiratory, and eye irritant. Therefore, the mucous membranes, skin, lungs, and eyes will suffer irritation from exposure to phosgene. Phosgene is not a central nervous system depressant or narcotic and is not a toxin to the kidneys or liver.

Which of the following does not apply to pull-outs and sweeps? A.Pull-outs prevent the operators hands from reaching the point of operation. B.Pull-outs required periodic inspection. C.Pull-outs are an acceptable safeguard. D.Pull-outs are a universal safeguard that can allow change-out of operators (employees) without adjustment of the machinery.

The correct answer is: A Pull-outs allow an operator to reach the point of operation for feeding. CPL 2-1.24 - National Emphasis Program on Mechanical Power Presses 29 CFR 1910.217

Supplied air respirators (SAR's) MUST be used in atmospheres: A.That are not immediately dangerous to life or health B.That contain asphyxiants C.That contain explosive vapors D.In confined spaces, where SCBA may be awkward

The correct answer is: A SAR's must be used in atmospheres where the threat to life or health is not immediate.

Plutonium, when taken into the circulatory system, will deposit in what areas of the body? A.Bone B.Liver C.Kidney D.Thyroid

The correct answer is: A Soluble plutonium deposits mainly in the bones. The insoluble forms remain in the lungs.

Calculate an employee's daily 8-hour TWA exposure to trichloroethylene if, in one 8-hour period, he spends 90 min at 300 ppm, 4.5 hrs at 200 ppm, and 2 hrs at 20 ppm. A.174 ppm B.199 ppm C.290 ppm D.384 ppm

The correct answer is: A TWA = [(1.5 hrs * 300 ppm) + (4.5 hrs * 200 ppm) + (2 hrs * 20 ppm)] / 8 hrs = 173.75 ppm

The primary factors that affect the development of cumulative trauma disorder (CTD) include all of the following EXCEPT: A.Age of the worker B.Intensity of force applied C.Repetitiveness of high risk tasks D.Lack of a proper rest period between high risk tasks

The correct answer is: A The age of a worker has little effect on the development of CTD. The accumulation of micro-injuries from excessive force is compounded by the frequency of repeating these high risk tasks (this takes into account the lack of rest between high risk tasks).

Methods of minimizing rates of repetition in jobs include all of the following EXCEPT: A.Dividing jobs to reduce the number of job elements B.Allow alternate use of limbs C.Allow self-pacing D.Allow frequent rotation between jobs which use different postures and muscles

The correct answer is: A The goal is to increase the number of job elements to reduce the repetitiveness of the task. This can only be done by combining jobs, not dividing them. The other answers help to reduce repetition through allowing change and alternatives to using the same muscles continuously.

Workplace air at 120 °F was sampled, and 850 liters was found to contain 70 mg of methylchloroform. What would the concentration of methylchloroform have been at room temperature (25°C)? (The molecular weight is 133). A.15 ppm B.16 ppm C.18 ppm D.20 ppm

The correct answer is: B 850 liters = 0.85 m^3 120°F = 322°K 25°C = 298°K 70 mg / 0.85 m^3 = 82 mg/m^3 ppm = [(82 mg/m^3 * 24.45) / 133] (322°K / 298°K) = 16.36 ppm

ALARA stands for: A.As long as regulations allow B.As low as reasonably achievable C.Alarm for alpha radiation area D.As low as reasonably accepted

The correct answer is: B ALARA stands for "As low as reasonably achievable." This applies to best practice recommendations for the control of exposures to radiation and chemicals.

A type of toxic reaction common in acute high level exposure to solvents is: A.Spontaneous aborted pregnancy B.Narcosis C.Anemia D.Pneumonitis

The correct answer is: B Acute high level exposure to a variety of solvents can produce disorientation, euphoria, giddiness, confusion, and eventually unconsciousness, paralysis, convulsions and death if exposure is not discontinued.

Radium is considered to be a _______ seeker when internal to the body. A.Lung B.Bone C.Total body water D.Thyroid

The correct answer is: B All Group II elements are considered bone seekers. They have a valence of 2+.

Silicosis is a dust disease from exposure to: A.Glass B.Crystalline SiO2 C.Amorphous silica D.Aluminum silicate

The correct answer is: B All of the answers contain the element silicon. However, only crystalline silicon dioxide (SiO2) causes the disease silicosis. Dust from glass, amorphous silica, and aluminum silicate are considered nuisance dusts and have minimal long term biological effects.

When a vacuum cleaner is used to clean up asbestos containing wastes it must have _________ exhaust ports. A.Well-maintained B.HEPA-filtered C.Pressure-demand D.Demand-only

The correct answer is: B All vacuum cleaners used for asbestos-containing material MUST have HEPA filtered exhausts. If the vacuum does not have this type of control, extremely high levels of airborne asbestos will result. 29 CFR 1910.1001 (k)(4)

Cumulative trauma disorders (CTD's) are rapidly becoming a major source of workers' compensation costs. The most common form is: A.Bursitis B.Carpal tunnel syndrome C.Kaolinosis D.Tendonitis

The correct answer is: B Carpal tunnel syndrome is a common disease of workers performing repeated exertions or movements of the fingers/hand and wrist which compress the median nerve in the carpal tunnel. It is often associated with tingling, pain, or numbness in the thumb and first three fingers, frequently resulting in lost time and workers' compensation costs.

In contrast to elemental mercury, cobalt salts are ______ absorbed from the gastrointestinal tract. A.Not readily B.Readily C.Not D.Both A and C

The correct answer is: B Cobalt salts are readily absorbed from the gastrointestinal tract. Elemental mercury is NOT readily absorbed (less than 0.01% of mercury is absorbed).

Workplace air at 120°F was sampled and 850 liters were found to contain 70 mg of methylchloroform. What would the concentration have been at STP? The molecular weight of methylchloroform is 133. A.15.1 ppm B.16.3 ppm C.25.4 ppm D.30.1 ppm

The correct answer is: B Convert the sample to mg/m^3 70 mg/.85 m^3 = 82 mg/m^3 ppmNTP = (mg/m^3(24.04))/MW ppm = (82 * 24.45)/133) * 322°K/293°K = 16.3 ppm Remember at NTP, T = 20°C = 293°K 120°F = 322°K Also at NTP (20°C & 1 atm) 1 mole of an ideal gas equals 24.04 liters.

A 20-ton crane has been out of service for 8 months for structural work. It should be proof-tested to _____ before being used. A.20 tons B.25 tons C.30 tons D.40 tons

The correct answer is: B Cranes shall be proof-tested to 125% of rated capacity after structural work. 20 tons * 125% = 25 tons 29 CFR 1910.179

If employees must work in a trench, the sides of trenches in unstable or soft material require a protective system (such as shoring) when the depth of the trench exceeds: A.4 ft B.5 ft C.6 ft D.7 ft

The correct answer is: B If employees are working in a trench, a protective system is required for any trench constructed through any material other than stable rock when the depth exceeds 5 feet. 29 CFR 1926.652 (a)(1)

The higher the linear energy transfer (LET), the _______ the injury to the tissue. A.Lower B.Higher C.There is insufficient information to make a determination. D.LET is not related to tissue injury.

The correct answer is: B If the LET is higher, tissue damage will be higher (i.e., more energy will be transferred to the tissue). LET is a function of the velocity and energy of the particle.

EPA has developed levels of protection for chemical protective clothing. One ensemble includes a liquid-splash protective suit, pressure-demand full facepiece SCBA, inner chemical resistant gloves, chemical resistant safety boots, two-way radio, and hard hat. This is an example of what level of protection? A.Level A B.Level B C.Level C D.Level D

The correct answer is: B Level B is essentially splash protection with SCBA. Level A is vapor protection with SCBA.

Organophosphorus insecticides act by: A.Inhibiting acetylcholine B.Inhibiting cholinesterase C.Blood chemistry imbalance D.Clotting action changes

The correct answer is: B Organophosphorus insecticides are designed to inhibit cholinesterase. They do not interfere with clotting or blood balances.

An occupational disease which is characterized by wrist drop, anemia, and abdominal cramps is: A.Mercury poisoning B.Lead poisoning C.Asbestosis D.Insecticide poisoning

The correct answer is: B Other symptoms of lead poisoning include lassitude, insomnia, pallor, eye irritation, anorexia, low weight, malnutrition, gingival lead line, and tremors.

Inhaled dust particles over 10 microns in diameter: A.Often penetrate to the lung alveoli B.Are often filtered out by the upper respiratory tract C.Clog the terminal bronchioles D.Are considered respirable

The correct answer is: B Particles over 10 microns are usually trapped in the upper respiratory system by the mucous-covered surfaces or are filtered out by hairs. They are therefore non-respirable, since they do not penetrate into the bronchioles and alveoli.

Some proteins have very complex structures. The forces that hold proteins in their quaternary structures are: A.Salt bridges B.Hydrophobic interactions C.Hydrophilic interactions D.Ion bridges

The correct answer is: B Quaternary structure is the result of multiple protein interactions (e.g. hemoglobin has two alpha and two beta chains that come together to form functioning hemoglobin). Salt bridges, disulfide bridges, and ion interactions all play a role in keeping the hemoglobin together, but hydrophobic interactions are felt to play the biggest role in holding proteins in their quaternary structures.

The term for the interaction of two toxins where the combined effect is greater than the sum of each is called: A.Additive B.Synergistic C.Potentiation D.Antagonistic

The correct answer is: B Synergistic effects occur when two substances act together to produce a toxic effect greater than the sum of each. For example, asbestos exposure and cigarette smoking produces a cancer risk much greater than the sum of each risk. Additive effects are the sum of each substance on the body. Potentiation is where one substance has no effect unless combined with a second substance, and antagonistic effects occur when two substances interfere with each others effects, giving an overall lesser effect.

What organization publishes ventilation standards for indoor air quality? A.OSHA B.ASHRAE C.NIOSH D.ANSI

The correct answer is: B The American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) publishes standards for ventilation on a periodic basis.

The main source of fire codes in the United States is from: A.ANSI B.NFPA C.OSHA D.UL

The correct answer is: B The National Fire Protection Association (NFPA) is the main source of fire codes in the United States

The part of the ear which contains the hair-like cells that detect sounds is the: A.Semicircular canals B.Cochlea C.Stapes D.Anvil

The correct answer is: B The cochlea is the organ which contains hair-like cells. The sound waves move the hairs at specific locations in the cochlea. The sites of hair movement correspond to the sounds' frequencies.

You are asked to evaluate a procedure to address a high pressure steam fitting leak. Which of the following safety-related caution steps should you ensure are included in the procedure and performed prior to making repairs? A.Use an intrinsically safe wrench B.Ensure system is shut down, bled, locked out, and tagged out C.Wrap line with electrician's tape before making repairs D.Patch leak with non-hazardous epoxy

The correct answer is: B The correct caution steps are as follows: Verify that the system is shut down Verify that the system is bled Ensure that appropriate lockout/tagout procedures have been implemented

The critical organ for biological damage from laser exposure is the: A.Whole body B.Eye C.Skin D.Immune system

The correct answer is: B The critical organ is the eye with a secondary organ of the skin.

A duct with a 12 in. diameter has an average duct velocity of 3,200 ft/min. What is the flow rate through this duct? A.1,600 cfm B.2,500 cfm C.2,700 cfm D.2,900 cfm

The correct answer is: B The cross-sectional area of the duct is 0.785 ft2. Q = AV Q = (0.785 ft2) 3,200 ft/min = 2,513 cfm

Given the emergent beam radiation exposure and MPE of a laser, the formula for calculating the minimum optical density of protective eye wear is: A.OD = Ho/MPE B.OD = log (Ho/MPE) C.OD = log (MPE/Ho) D.OD = MPE/Ho2

The correct answer is: B The minimum optical density is given as the log of the (beam radiation/MPE). OD = log (Ho/MPE)

Which range of UV radiation is the most hazardous to the eyes? A.240 - 260 nm B.260 - 280 nm C.280 - 300 nm D.300 - 340 nm

The correct answer is: B The most important ocular effect is photokeratitis caused by ultraviolet light exposure for the non-visual region of the spectrum. The peak wavelength for this effect is 270-280 nm.

The particle size which exhibits the greatest tendency to stay in the alveoli is: A.0.5 - 1.0 micron B.1 - 5 microns C.5 - 10 microns D.0 - 0.74 micron

The correct answer is: B The size for peak retention is 1 - 5 microns. Minimum retention occurs at about 0.5 microns.

Which of the following has a higher potential for toxic effect? A.Small particles/high density B.Small particles/low density C.Large particles/low density D.Large particles/high density

The correct answer is: B The smaller the particle and the lower the density, the better the chance for deposition deep in the lung, therefore increasing potential toxicity.

A NATURAL radionuclide that contributes significantly to a humans body radiation dose is: A.Tritium (H) B.Radioactive potassium () C.Radium () D.Uranium ()

The correct answer is: B Tritium is man-made and found in nuclear effluents. Radium and uranium are natural products but do not normally contribute to a person's radiation dose. Radioactive potassium is naturally occurring and widely distributed. It contributes significantly to human internal dose.

An operator of a degreaser tank noticed that the tank solvent (trichloroethylene) was leaking onto a flame under the tank. What is among your MAIN concerns? A.Trichloroethylene exposure B.Phosgene exposure C.Explosion exposure D.All of the above

The correct answer is: B When in contact with a flame, trichloroethylene decomposes to form the highly toxic gas, phosgene. Trichloroethylene is not flammable (explosion is very unlikely). Brief exposures to trichloroethylene itself is not as hazardous as brief exposures to phosgene.

If a material has a sound absorption coefficient of 0.80 that means that ______ percent of the sound energy in the wave will be ___________ . A.20, absorbed B.10 x log (0.20/0.80), reflected C.80, absorbed D.80, reflected

The correct answer is: C A sound absorption coefficient of 0.80 means that 80% of the sound energy in the wave will be absorbed. (20% will be reflected).

Which of the following is not true regarding two-hand trip safe guards for point of operation hazards? A.Two-hand trips require two separate switches to be located, such that the operator must use both hands to activate the machine. B.Two hand trips must be located more than 6 feet from the machine. C.Two hand trips must be in a fixed location. D.Two-hand trips do not specifically require a "holding time."

The correct answer is: C Articulating or extendable bars or control mounts, clearly established floor position for portable control stands. Other administrative controls may be used when it is not possible to mechanically or electrically fix the portable stand or station in position. CPL 2-1.24 - National Emphasis Program on Mechanical Power Presses 29 CFR 1910.217

All of the following are carcinogens EXCEPT: A.Asbestos B.Beta-naphthylamine C.DDT D.Nickel carbonyl

The correct answer is: C Asbestos causes mesothelioma, beta-naphthylamine causes bladder cancer, and nickel carbonyl causes lung cancer. DDT has not been shown to cause cancer.

At what sound level does an employer have to implement engineering or administrative controls to reduce the noise level in a work environment? A.When the 8-hour TWA exceeds 85 dBA B.When the 8-hour TWA exceeds 88 dBA C.When the 8-hour TWA exceeds 90 dBA D.When the 8-hour TWA exceeds 95 dBA

The correct answer is: C At 90 dBA (8-hr TWA) the employer must implement engineering or administrative controls unless proven not to be feasible. 29 CFR 1910.95 (b)(1)

Bladder tumors are most likely caused by: A.DDT B.PVC dust C.Beta-naphthylamine D.Methyl isocyanate

The correct answer is: C Beta-naphthylamine has been found to cause bladder tumors in humans. DDT, PVC, and methyl isocyanate are not human carcinogens.

Exposure to coal tar products has been shown to increase adverse effects from which of the following? A.IR radiation B.Asbestos C.UV radiation D.Chromates

The correct answer is: C Classic photosensitization of the skin is due to the synergistic effects of sunlight (UV radiation) and coal tar products.

Which type of asbestos is considered the worst from an occupational health perspective? A.Chrysotile B.Amosite C.Crocidolite D.Cristobalite

The correct answer is: C Crocidolite is associated with mesothelioma, a normally fatal type of cancer of the pleura. Cristobalite is a form of silica.

How much acetone would have to be evaporated into a room 15 ft x 12 ft x 10 ft to give a final concentration of 10 ppm at STP? (The specific gravity is 0.79, and the molecular weight is 58). A.1.0 ml B.l.3 ml C.1.67 ml D.1.9 ml

The correct answer is: C First determine room volume. 15 ft * 12 ft * 10 ft = 1800 ft^3 1800 ft3/ 35.3 ft3/m3 = 51 m^3 mg/m^3 = (ppm * MW)/22.4 = (10 * 58)/22.4 = 25.9mg/m^3 25.9 mg/m^3 * 51 m^3 = 1320.9 mg or 1.32 g 1.32 g/0.79 g/ml = 1.67 ml Remember at STP (0 °C & 1 atm) 1 mole of an ideal gas equals 22.4 liters

Infrared (IR) radiation causes greatest damage to the: A.Iris B.Cornea C.Retina D.All are damaged equally

The correct answer is: C IR radiation is not absorbed much by the cornea. It passes through and is absorbed by the lens and retina

This technique envisions a "primitive" or unprotected system and systematically evaluates the effects of adding various controls through a brainstorming approach. A.Brainstorming B.Primitive analysis C.Naked man D.Hazard control review

The correct answer is: C Naked man is the technique that envisions a "primitive" or unprotected system and systematically evaluates the effects of adding various controls through a brainstorming approach.

Where does the exchange of carbon dioxide and oxygen take place in the human body? A.The bronchioles B.Eustachian tubes C.Alveolar portion of the lungs D.Bronchus

The correct answer is: C Oxygen/carbon dioxide exchange occurs in the alveolar walls which contain the capillaries where diffusion occurs.

The size particle which has the greatest retention in the lung is: A.0.05 to 1 micron B.0.5 to 0.75 micron C.1 to 5 microns D.5 to 10 microns

The correct answer is: C Particles in the size range of 1 to 5 microns penetrate the lungs into the alveolar area where they have less chance of being cleared from the lung. Particles less than 1 micron tend to stay in the airstream and are breathed back out, while particles greater than 5 microns are captured in the upper respiratory tract and do not usually migrate to the lower portions of the lungs.

A mine's ventilation shaft has a total flow of 2,000 cfm. The shaft entrance is 10 ft x 10 ft. What is the velocity of the air at the entrance? A.2 ft/min B.3 ft/min C.20 ft/min D.3,000 ft/min

The correct answer is: C Q = AV 2,000 ft^3 = 100 ft^2 * V V = 20 ft/min

Radon exposure in the indoor environment results in radiation exposure to what part of the body? A.Skin B.Digestive tract C.Lungs D.Brain

The correct answer is: C Radon decays to produce radioactive products such as polonium, bismuth, and lead, which are deposited in the lung and can cause lung cancer.

An employee was exposed to the following noise levels: dBA Time 110 0.5 hours 90 2.0 hours 80 3.0 hours 85 2.5 hours To what level was the permissible noise exposure exceeded for an 8 hour period? A.Not exceeded B.Exceeded by 25% C.Exceeded by 50% D.Exceeded by 100%

The correct answer is: C Refer to Table G-16 in 29 CFR 1910.95 (b). To determine whether the permissible noise exposure limits were exceeded, calculate the dosage. For each noise level, add the actual dose divided by the permissible dose at that noise level. Dose = {[(110 dBA * 0.5 hr)/(110 dBA * 0.5 hr)] + [(90 dBA * 2 hr) / (90 dBA * 8 hr)] + [(80 dBA * 3 hr) / (80 dBA * 32 hr)] + [(85 dBA * 2.5 hr) / (85 dBA * 16 hr)]} Dose = 1.5 A dose of 1.0 is the maximum permitted; therefore, a dose of 1.5 exceeds the maximum by 50%.

What is the TLV of a mixture containing 35% by weight methylchloroform (TLV = 1,900 mg/m^3), 35% chloroform (TLV = 50 mg/m^3), and 30% perchloroethylene (TLV = 335 mg/m^3)? A.96 mg/m^3 B.96 ppm C.124 mg/m^3 D.124 ppm

The correct answer is: C TLV = 1/E (f / TLV) = 1 / [(0.35 / 1,900 mg/m3) + (0.35 / 50 mg/m3) + (0.3 / 335 mg/m3)] = 1 / 0.00808 m3/mg = 123.7 mg/m3

Calculate an employee's TWA when given the following exposures: 1 hour = 150 ppm 2 hours = 75 ppm 5 hours = 10 ppm A.35 ppm B.38 ppm C.44 ppm D.53 ppm

The correct answer is: C TWA = [(1 hr * 150 ppm) + (2 hrs * 75 ppm) + (5 hrs * 10 ppm)] / 8 hrs = 43.75 ppm

Determine an employee's daily 8-hour exposure to a solvent with a TLV of 100 ppm when the employee spends 1 hour at an operation where the concentration is 250 ppm, 4 hours at 200 ppm, and 3 hours at 100 ppm. A.84 ppm B.135 ppm C.169 ppm D.1,350 ppm

The correct answer is: C TWA = [(1 hr * 250 ppm) + (4 hr * 200 ppm) + (3 hr * 100 ppm)] / (8 hours) = 169 ppm

You gathered the following measurement data when assessing an employee's exposure to a hazardous airborne chemical: 6:00 a.m. - 9:00 a.m.; 100 ppm 9:00 a.m. - 11:00 a.m.; 200 ppm 11:00 a.m. - 12:00 p.m.; 0 ppm 12:00 p.m. - 2:00 p.m.; 100 ppm What is this employee's exposure TWA to this chemical? A.106 ppm B.110 ppm C.113 ppm D.120 ppm

The correct answer is: C TWA = [(3 hr * 100 ppm) + (2 hr * 200 ppm) + (1 hr * 0 ppm) + (2 hr * 100 ppm)]/(8 hr) = 112.5 ppm

Which of the following organizations publishes the National Electric Code? A.OSHA B.ANSI C.NFPA D.ASSE

The correct answer is: C The National Fire Protection Association (NFPA) publishes the National Electric Code (NEC). OSHA references the NEC in several regulations. The NEC is also known as NFPA 70.

Pick the appropriate formula used to calculate a safety margin. A.(Minimum strength / 2) B.(Minimum strength / maximum strength) - maximum strength C.(Minimum strength - maximum stress) / expected stress D.Minimum strength / 4

The correct answer is: C The appropriate formula to calculate a safety margin is one that applies the maximum and minimum stresses with the minimum strength to determine a safety margin over the expected stress.

The most significant wavelength for producing skin cancer is: A.200 - 220 nm B.250 - 280 nm C.280 - 320 nm D.350 - 400 nm

The correct answer is: C The predominant wavelengths associated with skin cancer are those in the 280 - 320 nm range with a peak around 297 nm.

A radiation area is an area where the dose may exceed 5 mrems in any hour, or there is the possibility of a dose of _____ mrems in any consecutive 5 days. A.10 B.50 C.100 D.1,000

The correct answer is: C The requirements for the definition of a radiation area are laid out by the NRC/OSHA and are 5 mrems in any one hour or the possibility of 100 mrems in any consecutive 5 days.

Work surface height for standing work places should be designed as follows for precision work: A.Below wrist height with padded rests for elbows B.Shoulder height with a back rest C.Above elbow height with padded forearm rests D.Standing work places should be discouraged

The correct answer is: C The work should be placed above elbow height for best posture and padded forearm rests should be provided to allow resting of arms on the surface. Work surfaces below elbow height may cause arm fatigue and shoulder height work will cause back and shoulder fatigue. Standing work places can be well designed to allow for low stress work with low fatigue. Adjustability will allow the employee to determine the best height for his or her needs.

When erecting scaffolding for a construction job site, guardrails and toeboards are required for any platform over ______ above the ground. A.5 ft B.8 ft C.10 ft D.12 ft

The correct answer is: C With the exception of needle beam scaffolds and floats, guardrails and toeboards are required on platforms over 10 ft above the ground. 29 CFR 1926.451 (h)(2)

"Bonding" a flammable liquid dispensing can refers to the process of: A.Connecting it to the earth B.Attaching it to a grounding strap C.Gluing it to the floor D.Connecting it to other conductive objects

The correct answer is: D "Bonding" refers to the connection of conductive objects by means of a conductor to minimize potential electrical differences between the objects. "Grounding" is the process of connecting the conductive objective to the ground. In flammable liquid dispensing, both "bonding" and "grounding" are important.

29 CFR 1910.119 requires affected employers to involve employees. This employee participation includes all of the following EXCEPT: A.Developing an employee participation plan B.Consulting with employees on the plan C.Providing employees with access to records D.Requiring the employer to commission a safety and health committee

The correct answer is: D 29 CFR 1910.119 (process safety standard) does not require safety and health committees. The employee participation section does require a plan, employee consultation on the plan, and employee access to records. 29 CFR 1910.119 (c)

The degree to which a person responds to the action of a toxic agent is dependent upon: A.Concentration and toxicity of the material B.Route of exposure C.Duration of exposure D.All of the above

The correct answer is: D All contribute to the individual's response to a toxic agent. Other factors such as age, sex, and nutritional status can markedly affect the response to a given insult.

Which of the following is adequate when isolating equipment to comply with lockout/tagout program requirements? A.Pulling a fuse on electrical equipment to guarantee a dead circuit B.Disconnecting the main power source to fully disable most machines C.Tightly shutting a high pressure valve before commencing maintenance work D.Physically locking the main power source and labeling it

The correct answer is: D All of the selections except "Physically locking the main power source and labeling it" fail to eliminate the hazard. Additional actions require physically "locking out" the energy source(s) and labeling it with a warning tag. 29 CFR 1910.147

The room designed to recharge and replace acid batteries for forklifts requires all of the following EXCEPT: A.Eyewash/safety shower B.Ventilation C.Facilities to neutralize electrolytes D.Blow-out construction

The correct answer is: D Blow-out construction is not required. 29 CFR 1910.178 (g)(2)

Which of the following properties do n-hexane and methyl n-butyl ketone have in common? A.Carcinogenic B.Neurotoxic C.Metabolized to 2,5-hexanedione D.Both B and C

The correct answer is: D Both n-hexane and methyl n-butyl ketone are metabolized to 2,5-hexanedione, a potent neurotoxin.

The process safety standard requires employers with covered processes to conduct compliance audits that include all of the following elements EXCEPT: A.Certification of compliance with the standard elements of the process safety standard B.Verification that procedures are working C.Written report with recommendations D.Verification that audits have been conducted annually

The correct answer is: D Compliance audits are required at least every three years. 29 CFR 1910.119 (o)

If 3,500 cfm of air is drawn through an 8 inch diameter duct, what is the velocity in the duct in feet per minute? A.800 ft/min B.1,000 ft/min C.1,020 ft/min D.10,230 ft/min

The correct answer is: D Duct cross-sectional area (in ft^2) is (D^2/4) = 0.35 ft^2 Q = A V V = Q / A = (3,500 ft^3/min) / 0.35 ft^2 = 10,227 ft/min

An employee was exposed to the following airborne hazardous chemical for 8 hours: Chemical TWA-TLV Actual Exposure TWA Ethyl ether 400 ppm 376 ppm Ethyl acetate 400 ppm 400 ppm Diethyl ketone 200 ppm 267 ppm By how much did the employee exceed the threshold limit value for this exposure? A.Exceeded by 27% B.Exceeded by 33% C.Exceeded by 133% D.Exceeded by 228%

The correct answer is: D Each TWA exposure dosage must be added when determining an employee's exposure to multiple hazardous chemicals. Add the actual exposure divided by the TLV for each chemical. Dose = (376 ppm/400 ppm) + (400 ppm/400 ppm) + (267 ppm/200 ppm) = 3.275 A dose of 1.0 is the maximum permitted; therefore, a dose of 3.28 exceeds the TWA-TLV for these chemicals by 228%.

All of the following factors increase the risk of developing skin cancer EXCEPT: A.Exposure to arsenic trioxide B.Previous exposure to sunlight C.Exposure to coal tar derivatives D.Exposure to carborundum

The correct answer is: D Exposure to carborundum may result in pneumoconiosis. Coal tar derivatives, sunlight, and arsenic are associated with increased risk of skin cancer.

A STEL is defined as a ____ minute TWA exposure that should not be exceeded at any time during the workday. A.1 B.5 C.10 D.15

The correct answer is: D Exposures above the TLV-TWA up to the short-term exposure limit (STEL) should be no longer than 15 minutes. The 15 minute STEL is a time-weighted average exposure that should not be exceeded even if the 8-hour TWA is within the TLV-TWA.

A supplied-air respirator must supply a quality of breathing air which contains the normal amount of oxygen, no more than 5 mg/m3 of condensed hydrocarbons, less than 10 ppm of carbon monoxide, and other requirements. What type of breathing air does this describe? A.Grade I B.Class IV C.Type AA D.Grade D

The correct answer is: D Grade D breathing air is required by OSHA and its quality is specified in ANSI/CGA Commodity Specification for Air. In addition to those requirements previously stated, the air must also have no pronounced odor and have less than 1,000 ppm of carbon dioxide. The oxygen concentration must be between 19.5% and 23.5% by volume. ANSI/CGA G-7.1 29 CFR 1910.134 (i)(1)(ii)

Which two mechanisms work together to increase exposure to particulates? A.Respiration and inhalation B.Absorption and ingestion C.Penetration and inhalation D.Inhalation and ingestion

The correct answer is: D Inhalation contributes to exposure by ingestion. Particles caught in the upper respiratory tract are swept to the throat and swallowed.

Any of the following are major cause(s) of electrical shock EXCEPT: A.Ungrounded frames or inadequate grounding of frames on noncurrent-carrying parts of electrical machinery and tools B.Inadequate protection of exposed current-carrying parts of electrical installations C.Inadequate insulation of electrical conductors D.Ground fault circuit interrupters (GFCI's)

The correct answer is: D Listed are the three major causes of electrical shock. The National Electric Code (NEC) provides instructions for eliminating shock hazard from the workplace. GFCI's are designed to protect people from shock by quickly breaking the circuit when detecting a ground fault.

Chronic yellow phosphorous poisoning results in which of the following? A.Peripheral nerve damage B.Grey pigmentation of the gums C.Metal fume fever D.Bone necrosis

The correct answer is: D Phosphorous mainly affects the skeletal system and the liver. The classic symptom is phossy jaw, a degradation of the mandible (jaw bone).

What ventilation is required in a circular duct of 1 ft^2 to control a contaminant 5 ft from the duct? A velocity of 50 ft/min is required to entrain the contaminant, and the hood has a hood constant of 1.00. A.800 cfm B.1,300 cfm C.2,600 cfm D.13,000 cfm

The correct answer is: D Q = CV (10D^2 + A) = 1.00 * 50 ft/min * [10 (5 ft)^2 + 1 ft^2] = 12,550 cfm

Which of the following does NOT determine biological effect from radiation exposure? A.Penetration B.Ion formation C.Type of radiation D.Source of radiation

The correct answer is: D The source of the radiation does not determine effect. It does determine the type of radiation and the energy of the radiation.

Which of the following is not one of the four physical classifications of toxic substances in air? A.Solid aerosols B.Liquid aerosols C.Gases D.Asphyxiants

The correct answer is: D The term "asphyxiant" is not a physical classification. It is a toxic property of a substance. The missing physical classification is "vapors".

Respirators for use in an IDLH atmosphere must be at least: A.NIOSH-approved full face piece SCBA (pressure demand) rated for 30 minutes B.NIOSH-approved full face piece SAR (pressure demand) with a self-contained auxiliary air supply C.NIOSH-approved respirators approved for escape from the specific IDLH atmosphere that can be expected D.All of the above

The correct answer is: D These are the only respirators permitted to be used in an IDLH or potential IDLH environment. NIOSH-approved "escape only" respirators are only approved in potential IDLH environments that are not routinely IDLH. Note that oxygen-deficient atmospheres (less than 19.5% oxygen content) are considered IDLH. 29 CFR 1910.134 (d)

A container with 100 ml of methylene chloride is spilled into an unventilated room 4 m x 4 m x 10 m. Determine the airborne concentration at 25 °C after it has fully evaporated. (The specific gravity is 1.336 and the molecular weight is 85.) A.150 ppm B.100 ppm C.220 ppm D.240 ppm

The correct answer is: D Volume of room = 4 m x 4 m x 10 m = 160 m^3 100 ml * 1.336 g/ml = 133.6 g = 133,600 mg 133,600 mg/160 m^3 = 835 mg/m^3 [(835 mg/m^3 * 24.45) / 85] = 240.2 ppm

A worker is exposed to xylene (the molecular weight is 106) during her 8-hour work day in the following concentrations: 2 hours at 100 ppm 2 hours at 150 ppm 4 hours at 50 ppm. What is her TWA exposure? A.50 ppm B.56 ppm C.77 ppm D.88 ppm

The correct answer is: D ppm = [(2 hrs * 100 ppm) + (2 hrs * 150 ppm) + (4 hrs * 50 ppm)] / 8 hrs = 87.5 ppm

Sources of ozone include all of the following EXCEPT: A.Electric arc welding B.Office photocopying machines C.Ultraviolet quartz lamps D.Video display terminals (computer monitors)

The correct answer is: D Ozone can be produced by the interaction of ultraviolet light, electric arcs, and oxygen. Sources of ultraviolet light and electric arcs include arc welding, photocopy machines, laser printers, and ultraviolet lamps. Video display terminals do not produce ozone.

One risk of plasma torch welding is the possibility of developing: A.Sunburn B.Keratoconjunctivitis C.Ulcers D.Both A and B

The correct answer is: D Plasma torches can produce temperatures of 6,000°C. Intense ultraviolet radiation can result. The levels can be so high that unprotected skin and eyes can be burned. Ozone is also a concern in plasma torch operations.

ANSI A13.1 provides a scheme for the identification of piping systems. What is the standard color used to identify protective materials? A.Blue-yellow B.Bright blue C.Green D.Red

The correct answer is: B Bright blue is the standard color used to identify protective materials.

The occupation most likely to encounter metal fume fever is: A.Electroplater B.Welder C.Firefighter D.Miner

The correct answer is: B Metal fume fever is an acute condition of short duration caused by a brief high exposure to the freshly generated fumes of metals, such as zinc or magnesium or their oxides. Symptoms appear from four to twelve hours following exposure and consist of fever and shaking chills.

Ultraviolet (UV) radiation causes greatest damage to the: A.Lens B.Cornea C.Retina D.All are damaged equally

The correct answer is: B The cornea is the most sensitive to UV light. A common example of injury to the cornea is welder's flash (photokeratitis).

To what are most IAQ issues attributed? A.Indoor air contaminants B.Outdoor pollution sources C.HVAC system maintenance/operation D.Most causes are not determined

The correct answer is: C According to NIOSH, heating, ventilating, and air conditioning systems are the leading determined cause of IAQ problems. The other answers are also causes, but to a lesser degree.

A backdraft hood is especially useful, from an industrial hygiene standpoint, because it: A.Is unusually efficient B.Encloses the process C.Draws contaminants away from employee breathing zones D.Is less expensive than other types of local exhaust ventilation

The correct answer is: C The backdraft hood acts by pulling contaminants away from the workers breathing zone towards the back of the equipment.

The effects of the failure are traced through the system and the ultimate effect on task performance is evaluated. This process is called: A.Failure effects analysis B.Fault hazard analysis C.Failure modes and effects analysis D.Critical item

The correct answer is: C The effects of the failure are traced through the system and the ultimate effect on task performance is evaluated. This process is called "failure modes and effects analysis".

An experiment involving sound requires the use of an oscilloscope. On the screen, the loudness of sound should be viewed as a function of: A.Wavelength B.Frequency C.Amplitude D.Weighted sound levels

The correct answer is: C The intensity of sound is characterized by its loudness, (e.g., the louder the sound, the greater the amplitude of its wave motion). On the oscilloscope, the sound wave would appear as an alternating wave motion whose amplitude adjusts to the sound volume.

The factor which is most responsible for dust particles gaining entrance to the terminal airsacs of the lung is: A.Composition of the dust B.Concentration C.Particle size D.Condition of the lung

The correct answer is: C The most important factor is the particle size. The particle must be of the right size to reach the alveoli.

A process to identify hazards and to recommend risk reduction alternatives in procedurally controlled activities during all phases of intended use is called: A.Preliminary hazard analysis B.Risk assessment C.Operating and support hazard analysis D.Fault tree analysis

The correct answer is: C The operating and support hazard analysis technique is a process to identify hazards and to recommend risk reduction alternatives in procedurally controlled activities during all phases of intended use.

Which of the following is the preferred technique to prevent aerosol generation? A.Dry sweeping B.Wet scrubbing C.Air blowing D.Central vacuum

The correct answer is: D All mechanical cleaning techniques generate significant amounts of aerosols. A central vacuum system removes material from the area.

The principle organ(s) at risk from laser exposure is (are) the: A.Skin B.Eye C.Bone D.Both A and B

The correct answer is: D Most biological effects of laser radiation are attributable to the heating of tissue. The two organs most accessible to laser radiation are the skin and eyes. Therefore, they are the organs at risk.

OSHA approves: A.Respirators B.Safety-toed footwear C.Safety hard hats D.OSHA does not approve safety equipment

The correct answer is: D OSHA does not approve any type of personal protective equipment.

The following quantities of flammable and combustible liquids must be safely stored. Class I - 35 gal Class II - 35 gal Class III - 50 gal Which of the following is the BEST storage recommendation? A.Provide two approved metal storage cabinets. B.Disburse the materials throughout the assembly area. C.Provide one approved metal storage cabinet. D.Insist the quantities be reduced.

The correct answer is: A NFPA 30 (Flammable and Combustible Liquids Code) states that not more than 120 gallons of Class I, Class II, and Class IIIA liquids may be stored in a storage cabinet. Of this total, not more than 60 gallons may be of Class I and Class II liquids.

A tank truck has been involved in a fire. By the time you arrive, the label on the truck only indicates that the material has a pH of 12. What does this tell you? A.The material is flammable B.The material is acidic C.The material is basic D.The material is neutral

The correct answer is: C A pH of 12 is a basic solution. A pH less than 7 is acidic A pH of 7 is neutral A pH greater than 7 is basic.

A 6 in. duct 100 ft. long is carrying 200 cfm of air with a friction loss of 5.2 in. of water. If the airflow is increased to 300 cfm, what is the new friction loss? A.5.2 in. of water B.7.8 in. of water C.11.7 in. of water D.17.6 in. of water

The correct answer is: C Remember that friction loss varies directly with the square of the velocity. Friction loss = 5.2 in. of water * (300/200)^2 = 11.7 in. of water

A sound absorption coefficient of 0.6 means that ______ % of the sound energy in a wave will be reflected. A.40 B.60 C.10(log 0.6/0.4) D.0.6 * log (0.4/0.6)

The correct answer is: A A sound absorption coefficient of 0.6 means that 40% of the sound energy in the wave will be reflected and 60% will be absorbed.

A room ventilation system has been designed to provide 5 cfm of outdoor air per person. Which statement best describes the situation? A.The ventilation rate would be insufficient for most environments. B.The ventilation rate is sufficient for offices only. C.The room must be at least 10,000 ft2. D.The room cannot be occupied by more than 7 people.

The correct answer is: A According to the ASHRAE Standard 62-1989, the minimum outdoor air requirements are 20 cfm/person in an office environment. Manufacturing environments would require more outdoor air, depending on the chemicals used and local ventilation requirements. The 20 cfm/person standard is independent of room size and is based on 7 people per 1,000 ft^2 of floor space.

Drug and substance abuse is a potential problem in the work place. Organizations have a responsibility to prevent drug and substance abuse from creating a hazardous work environment. Drug and substance abuse may be an issue with an employee that: A.Experiences frequent sick days, tardiness, unusual behavior B.Is known to be experiencing family problems and using EAP services C.Works extensive and unusual hours and uses email as the primary form of communication with coworkers D.Constantly contradicts or corrects the supervisor and is constantly getting involved in other employees projects

The correct answer is: A An individual experiences frequent sick days, tardiness, repeated unsafe work practices and/or other unusual behavior, may have a drug or substance abuse problem.

Which is an example of an unfired pressure vessel? A.Boiler B.Steam jacketed kettle C.Any vessel directly experiencing flame D.Copper jacketed steam kettle

The correct answer is: B An unfired pressure vessel does not have a direct flame impacting on it. A steam jacketed kettle is such an example.

Methods to effectively control Legionnaires Disease include all of the following EXCEPT: A.Continuous feed biocide B.Locate make-up air intakes upwind from cooling towers C.Periodic cleaning of cooling water systems D.Sampling to ensure bacterial control

The correct answer is: A Continuous feed biocides can cause resistant strains of bacteria in the cooling system. It is best to alternate biocides to prevent resistance. Prevention of cooling tower aerosols into the building makeup air will prevent bacteria from entering the ventilation system. Complete periodic cleaning and sampling of the cooling water systems have proven effective.

When selecting a dispersion model it is important to consider the: A.Limitations and assumptions of the model B.Ground characteristics of the local geography C.Location of the release relative to wind speeds D.Computing resources necessary to compute the model

The correct answer is: A Dispersion models are a valuable tool for planning, risk assessment and incident investigation. The specific needs of the situation to be modeled need to be coordinated with the limitations and assumptions of the model to be used.

An inductive risk analysis technique that explores different responses to "challenges", or lines of assurances, is called: A.Event tree analysis B.Fault tree analysis C.Logic analysis D.Bottom-up assessment

The correct answer is: A Event tree analysis is an inductive technique that explores different responses to challenges.

The technique in which the failure or malfunction of each component is considered and the effects of the failure traced throughout the system is identified with: A.Failure mode and effects analysis B.Fault hazard analysis C.Fault tree analysis D.THERP

The correct answer is: A Failure mode and effects analysis (FMEA) is an analytical technique in which the failure or malfunction of each component is considered, including the mode of failures. The effects of the failure are traced through the entire system and their effects on the system performance is evaluated

A switch has 4 components. Each component has a failure rate of "a". The components are connected in series. What is the switch's failure rate? A.4a B.(4a) + 1 C.a(a + 4) D.a^4

The correct answer is: A For "n" components in series, the overall failure rate is the sum of the single components' failure rates.

The toxic chemical which caused the Bhopal disaster had the acronym MIC. This stood for: A.Methyl isocyanate B.Methyl isocarbamate C.Methyl isochromate D.Methyl isocyanurate

The correct answer is: A Methyl isocyanate was the toxic chemical released during the Bhopal disaster.

Which of the following was a commonly used insulating oil for older transformers and has been found to have severe environmental issues? A.PCB's B.PCP's C.PCV's D.TLV's

The correct answer is: A PCB's (polychlorinated biphyenls) were commonly used in transformers prior to the 1970's. They are now known to have significant adverse environmental impacts.

The geometry of the source of a release is important to the modeling process. Information about the sources that is important to try and obtain is: A.The dimensions of the pipe or tank, the size of release orifice and location of release orifice B.The size of the source, temperature, age and last inspection C.The temperature, last risk assessment, dimensions of tanks and pipes, size of the orifice D.State of materials, size and dimensions of the source container and material characteristics

The correct answer is: A The geometry of the source is related to the release rate. Source geometry factors that influence release rate are the size of the orifice, location of the orifice related to liquid level, the dimensions of the container, whether the container is partially or completely buried, if the orifice is a pipe or a breech of a tank. These factors can all greatly influence the release rate of the material and subsequently play a significant role in modeling a release.

A certain hazard exists. Arrange the following hazard control steps in the appropriate order for consideration. 1. Install physical guards to protect employees from the hazard 2. Re-design the process to eliminate the hazard 3. Educate personnel of the hazard A.2, 1, 3 B.3, 1, 2 C.2, 3, 1 D.1, 3, 2

The correct answer is: A The proper sequence in hazard control is to engineer out, guard, and educate.

The voltage on the secondary side of a step-down transformer is _______ the voltage on the primary side. A.Lower than B.Higher than C.The same as D.Not related to

The correct answer is: A The secondary side of a step-down transformer features the "stepped down" voltages; therefore, the secondary side is of lower voltage.

A construction worker operating a jackhammer would be most affected by vibrations in the: A.1 - 125 Hz range B.500 - 1,000 Hz range C.2,500 - 5,000 Hz range D.10,000 - 25,000 Hz range

The correct answer is: A The use of jack hammers without protective gloves can lead to white finger disease, or Raynaud's Phenomenon, a deadening of the nerves due to the vibration from the jack hammer. The vibration frequency that is most hazardous is between 1 - 125 Hz.

What type of emergencies would you expect to find at a TSDF? A.Those involving hazardous wastes B.Those involving trash or rubbish C.Electrical shock emergencies D.Those involving compressed gas cylinders

The correct answer is: A Treatment, storage, and disposal facilities (TSDF's) are required to have an emergency response plan for all emergencies involving hazardous substances. OSHA's hazardous waste operations and emergency response (HAZWOPER, 29 CFR 1910.120) is the standard that details program requirements.

ANSI Z35.1 provides the specifications for industrial accident prevention signs. What arrangement is appropriate to indicate caution against lesser hazards? A.Yellow background color, black lettering B.Black lettering on white background C.Light blue background color, black lettering D.Black lettering on orange background

The correct answer is: A Yellow background color with black lettering is the appropriate arrangement to indicate caution against lesser hazards.

In the application of the principles of guarding, what does Zero Mechanical State (ZMS) mean? A.All energy sources are neutralized B.All electrical energy is off C.Guards are not effective D.All electrical energy is locked and tagged out

The correct answer is: A ZMS is discussed in ANSI Z-241.1 as the state in which all energy sources are neutralized.

Which of the following designs will NOT allow equipment to operate in a failed mode? A.Fail-active B.Fail-passive C.Fail-safe D.Fail-operational

The correct answer is: B A fail-passive system shuts down the equipment.

Hazardous locations are areas where flammable liquids, gases, or vapors, combustible dusts, or other easily ignitable materials exist in sufficient quantities to produce an explosion or fire. Hazardous locations are classified as Class I, Class II, or Class III. Which one of the following statements is NOT true? A.Class I locations are those in which flammable vapors and gases may be present. B.Class II locations are those in which combustible liquids may be found. C.Class III locations are those in which there are ignitable fibers and flyings. D.Class I and Class II locations are subdivided into groups of gases, vapors, and dusts having similar properties.

The correct answer is: B Class II locations are those in which combustible DUST may be found.

Generators of between 100 and 1,000 kg of non-acutely hazardous wastes in a calendar month are commonly called: A.Conditionally exempt small quantity generators B.Small quantity generators (SQG) C.Owners/operators of TSDF's D.Large quantity generators

The correct answer is: B Conditionally exempt small quantity generators are limited to no more than 100 kg of non-acutely hazardous wastes in a calendar month. Large quantity generators are those generating more than 1,000 kg (2,200 lb) of non-acutely hazardous wastes in a calendar month.

A disposable dust mask has a protection factor of approximately: A.2 B.5 C.10 D.50

The correct answer is: B Disposable respirators such as dust masks have protection factors of around 5. The protection factor (PF) is the ratio of the contaminant concentration outside the mask to the concentration inside the mask. A PF of 2 is less than most respirators and a PF of 10 is the protection factor for half face piece cartridge respirators. A PF of 50 is the protection factor associated with demand SAR's.

At what employee noise exposure level (with a TWA over 8 hours) does OSHA require a hearing conservation program? A.85 dB B.85 dBA C.90 dB D.90 dBA

The correct answer is: B Employees whose TWA noise exposure equals or exceeds 85 dBA over 8 hours are required to be included in a hearing conservation program. The PEL for noise exposure is an average of 90 dBA for 8 hours. 29 CFR 1910.95 (c)(1)

When tested, a door hinge fails 4 times out of 1,000,000 operations. What is the hinge's failure rate? A.4 x 10^-5 failures/attempt B.4 x 10^-6 failures/attempt C.4 x 10^-7 failures/attempt D.4 x 10^-8 failures/attempt

The correct answer is: B Failure Rate = 4 failures / 1,000,000 attempts = 4 x 10-6 failures/attempt

A HEPA filter is 99.97 % effective at capturing monodisperse particles _____ microns or larger in diameter. A.0.1 B.0.3 C.0.5 D.1.0

The correct answer is: B HEPA filters are 99.97% efficient at collecting monodisperse particles 0.3 microns or larger.

The technique that selects the undesired outcome and all possible mechanisms of occurrence is: A.Failure mode and effects analysis B.Fault tree analysis C.Fault hazard analysis D.THERP

The correct answer is: B In fault tree analysis, an undesired event is selected and all possible mechanisms of occurrence of the event are diagrammed in the form of a tree. The branches of the tree are continued until independent events are reached. Probabilities are determined for the independent events and after simplifying the tree, both the probability of the undesired event and the most likely chain of events leading up to it can be computed.

Equipment that monitors leachate is used with: A.Air scrubbers B.Hazardous waste disposal C.Incinerators D.Gas fired boilers

The correct answer is: B Leachate is a combination of groundwater or surface water that has infiltrated the hazardous solid waste and suspended solid matter, microbial waste products, heavy metals, and other chemical substances in a hazardous waste landfill. Leachate comes to the surface or percolates down to the groundwater. Analysis equipment is used to determine the types of heavy metals, chemicals, or biological agents found in the leachate.

Most chain and sling failures can be avoided if: A.The chains and slings are replaced more frequently B.A proper inspection procedure is followed C.Hooks, rings, chain links, and couplings are made of wrought iron D.The angle between the legs of a chain sling and the horizontal are decreased

The correct answer is: B Most signs of chain failure can be detected before failure occurs if the proper inspection procedures are followed. A good inspection plan provides for two inspections; one daily inspection performed by personnel using the chain, and a monthly inspection with a full written, dated, and signed report by a management representative. 29 CFR 1910.179 (j)(2) (Alloy steel is the standard material used for chains and accessories and is now generally used instead of wrought iron. Decreasing the angle between the legs of a chain sling and the horizontal increases the load in the sling legs)..

A hazardous waste generator is required to obtain a permit, license, or other prior written approval from the EPA before generating waste. A.True B.False C.Depends upon the waste being generated D.Not enough information

The correct answer is: B No permit, license, or other written approval is needed from the EPA to generate a hazardous waste. However, both large and small quantity generators must obtain an EPA identification number prior to SHIPPING hazardous wastes offsite. Conditionally exempt small quantity generators (those that generate less than 100 kg/month of non-acutely hazardous wastes) are not required to obtain an EPA identification number. Generators storing hazardous wastes beyond the accumulation period (90 days for large quantity generators) are required to pursue a RCRA permit, as are generators that treat or dispose of hazardous wastes on-site in non-exempt units.

Which of the following materials is essentially opaque to the ultraviolet light in normal sunlight? A.Quartz glass B.Normal window glass C.Stratospheric oxygen D.Water vapor

The correct answer is: B Normal window glass is essentially opaque to UV less than 300 nm. Oxygen and water vapor are obviously not opaque because the UV penetrates to the surface of the earth. Quartz glass also allows UV to penetrate. These types of glass that transmit UV are needed for germicidal lamps and similar operations.

Which is the best option for waste management? A.Reclamation B.Reduction C.Recycling D.Reuse

The correct answer is: B Reduction of waste is the first and best option when determining a waste management strategy. The next best options in order are: reuse, recycle, and reclaim.

The process of determining safety goals, allowing supervisors a chance to perform, providing assistance along the way, and rewarding them according to their progress is known as which of the following? A.Management by Exception B.Safety by Objectives C.OSHA Star Program D.Motivation-Hygiene Theory

The correct answer is: B Safety by Objectives is the process of determining safety goals, allowing supervisors a chance to perform to meet these goals, providing assistance along the way, and rewarding the supervisors according to their progress in achieving the stated goals.

When tested, a door hinge fails 4 times out of 1,000,000 operations. What is the hinge's success rate? A.99.996 x 10^-2 successes/attempt B.99.9996 x 10^-2 successes/attempt C.99.996 x 10^-3 successes/attempt D.99.9996 x 10^-3 successes/attempt

The correct answer is: B Success Rate = 999,996 successes/1,000,000 attempts = 99.9996 x 10^-2

HEPA filters are individually tested with an aerosol with a mean diameter of approximately 0.3 microns. This is because: A.The 0.3 microns represents the peak retention in humans B.The HEPA filters have a maximum particle penetration of about 0.3 microns C.This is the smallest hazardous particle D.This is the smallest test aerosol

The correct answer is: B The 0.3 micron particle is the most likely particle to penetrate due to the design of the HEPA filter.

Given two independent events, the probability of their joint occurrence is the product of their independent probabilities of occurrence. What is the probability of getting two sixes when rolling a pair of dice? A.0.010 B.0.028 C.0.167 D.0.28

The correct answer is: B The probability of getting any one number on a single die is 1 out of 6; therefore the probability of getting two sixes is: (1 / 6)(1 / 6) = 1 / 36 = 0.028

What is the control terminology in common use for preventing the transmission of bloodborne pathogens? A.AIDS Quarantine B.Universal Precautions C.HIV Precautions D.HBV Protection

The correct answer is: B The term "Universal Precautions" is a set of work practices to prevent the spread of the HIV and other bloodborne pathogens.

"Hot working" of metals refers to: A.Power presses B.Foundries C.Shears D.Punches

The correct answer is: B The term "hot working" refers to foundry operations where the metals are heated to their melting points and are then poured.

Velocity pressure in a ventilation system is always: A.Negative B.Positive C.Equal to total pressure D.Equal to static pressure

The correct answer is: B Total pressure = static pressure + velocity pressure Since velocity pressure is always exerted in the direction of flow, velocity pressure is always positive.

The risk value for a given hazardous event is a measurement that combines all of the following variables EXCEPT: A.Frequency of process B.Unanticipated loss C.Exposed systems D.Likelihood

The correct answer is: B Unanticipated loss is not a variable for the risk value of a given hazardous event.

The risk associated with a given undesirable event is a measurement that combines all of the following variables EXCEPT: A.Expected frequency of the event B.Unanticipated losses C.Estimated consequence from loss of business D.Anticipated severity of the event

The correct answer is: B Unanticipated losses are those which remain unknown until AFTER the undesirable event occurs. The risk of an undesirable event combines the frequency of the loss with all of the anticipated losses.

A flammable liquid with a flash point of 63°F and a boiling point of 110°F would be classified by NFPA as a: A.Class I liquid B.Class IA liquid C.Class IB liquid D.Class II liquid

The correct answer is: C A Class IB liquid is a flammable liquid with a flash point below 73°F and a boiling point above 100°F.

A hood that surrounds the contaminant source and prevents it from ESCAPING into the workroom and entering the worker's breathing zone is a(n): A.Capturing hood B.Receiving hood C.Enclosing hood D.Canopy hood

The correct answer is: C A hood that is used to prevent the contaminant from escaping must ENCLOSE the contaminant source.

A flood destroys your company's operations facility. After the emergency management issues are addressed, your company implements several plans to: recover critical files and information that had been stored offsite, set up a temporary facility from which operations can be conducted, and inform customers of the situation and how they will be served. These plans are among examples of a comprehensive loss control activity called: A.Emergency management/emergency response B.Situational awareness C.Business interruption recovery/business continuity D.Inland marine preparedness

The correct answer is: C Business continuity planning is a key part of a loss control program. Such plans should include recovering corporate information, setting up operations, and financing temporary operations until a new facility can be commissioned. Depending upon the risk of a natural disaster, some companies purchase business interruption insurance to help finance operations.

The primary hazard associated with operating gasoline-powered industrial trucks in unventilated spaces is: A.Human exposure to explosions B.Human exposure to cardon dioxide (CO2) C.Human exposure to carbon monoxide (CO) D.Human exposure to nitrogen oxides (NOx)

The correct answer is: C Carbon monoxide is the primary human exposure hazard when operating gasoline-powered trucks within enclosed spaces.

Dispersion models are effective tools for all the following except: A.To evaluate how an incident occurred in the investigative process B.For pre-incident planning C.For risk assessment of unknown materials D.For real time management of incidents

The correct answer is: C Dispersion models are effective tools in pre-incident planning for sources of known materials, real time incident management when the material involved has been identified and in post incident investigation. Dispersion models require physical and chemical characteristics of the materials being modeled and are not effective tools for evaluation of unknown materials.

Which of the following are safety devices installed in boilers to relieve pressure? A.Blow down pipes B.Blow down valves C.Fusible plugs and safety valves D.Pressure relief pumps

The correct answer is: C Fusible plugs are designed to relieve pressure and to indicate certain conditions that contribute to low water (which causes pressure build-up). Safety valves will automatically relieve excess pressure or vacuum, that would otherwise damage equipment or result in injury to personnel. The selection, fabrication, installation, testing and replacement of safety valves and fusible plugs should be in accordance with the ASME code.

What control measures can be taken for adequate protection against external radiation hazards? A.Use lead shielding and protective equipment B.Follow the principles of the inverse square law C.Limit exposure time, work at a safe distance, and use barriers D.Use written procedures, employee training, personal protective equipment, and signage

The correct answer is: C Gamma rays, X-rays, and neutrons are the most penetrating radiations and usually constitute the major external hazards. There are three principal factors that provide the basis for radiation protection, namely: time, distance, and shielding. TIME - To control personnel exposure, the dose rate from a radiation source may be measured and appropriate limits placed on the working time for control of the dose to the individual DISTANCE - The intensity of a radiation field decreases as you move further away from the radiation source. The relation between radiation exposure rate and distance follows the inverse square law. SHIELDING - Since ionizing radiation will interact with most materials, in principle, anything can be used for shielding. Some materials, however, like lead, make more efficient shields than do others.

Compared to local exhaust ventilation, dilution ventilation: A.Is more suitable for highly toxic substances B.Is very good for ventilating point-source emissions C.Short circuiting of exhaust is less important D.Uses less air than local exhaust ventilation

The correct answer is: C General dilution ventilation is not appropriate for point-source emissions or for use with highly toxic materials. In these situations, local exhaust ventilation should be used. Because of these limitations, short circuiting of exhaust is less critical than in local exhaust ventilation.

In the cyanide electroplating of brass, which of the following components could be released into the atmosphere? A.HCl, HNO3 B.NaOH C.Cyanide salts, NH4OH D.Zn salts

The correct answer is: C HCl and HNO3 should never be used around cyanides because of potential for formation of HCN. Cyanide salts are commonly used in electroplating.

The most effective way to reduce accidents is to: A.Train employees to be more safety conscious B.Modify employee behavior C.Design inherent safety features into systems D.Rotate employees through many jobs

The correct answer is: C Hazards can be effectively mitigated or eliminated through system design, whereas hazard reduction through changing human behavior is limited and requires continuous reinforcement.

Which of the following is NOT an engineering control? A.Ventilation B.Operating procedure change C.Job rotation D.Substitution

The correct answer is: C Job rotation is an administrative control, since the people have changed, not the process. The others are engineering controls to the process.

In an assembly of 4,321 adults, 1,792 are college graduates. What is the probability (to the nearest tenth) that a person chosen at random from this group is NOT a college graduate? A.0.4 B.0.5 C.0.6 D.0.7

The correct answer is: C Of the 4,321 adults, (4,321 - 1,792) are NOT college graduates. The probability of choosing one of these people is: (4,321 - 1,792) / 4,321 = 0.6 (to the nearest tenth).

A switch has three parts connected in series. Each part has a failure rate of 0.2. Failure of any part causes the switch to fail. What is the switch's failure rate? A.0.008 B.0.4 C.0.6 D.1.0

The correct answer is: C Series Probability = 0.2 + 0.2 + 0.2 = 0.6

A microscopic dispersion of a solid in gas, where particles are usually less than 0.1 microns in diameter, is called which of the following? A.Dust B.Gas C.Smoke D.Vapor

The correct answer is: C Smoke is a microscopic dispersion of a solid in gas, particles are usually less that 0.1 microns in diameter.

A bleeder valve on a furnace fails after 20,000 days of operation. If the valve operates once per day, what is its success rate? A.0.995 successes/attempt B.0.9995 successes/attempt C.0.99995 successes/attempt D.0.999995 successes/attempt

The correct answer is: C Success Rate = No. of successes / No. of attempts = 19,999 successes / 20,000 attempts = 0.99995 successes/attempt

All of the following are true about vapor dispersion models except: A.Models valuable tools in pre-incident planning and evaluation B.Models are good risk assessment tools C.Models are all complex and difficult to use D.Each model has unique assumptions and limitations

The correct answer is: C There are a variety of dispersion models available ranging in cost from free to thousands of dollars. Some models are relatively simple to use while others require detailed information (including geographical information for the specific location to be modeled). Dispersion models should be selected based on the application and an evaluation of the specific model's assumptions and limitations to assure the model will meet the requirements of its proposed use

A key hazard associated with manufacturing polyurethane plastics is the potential for exposure to: A.Amines B.Phenolics C.Di-isocyanates D.Epoxy resins

The correct answer is: C Urethane polymers are formed by polyaddition reactions between a di-isocyanate and a polyhydroxyl compound. MDI (methylene bisphenyl-isocyanate) and TDI (toluene di-isocyanate) are the most common isocyanates used.

An air dispersion of molecules of a substance that is liquid or solid in its normal state at standard temperature and pressure is: A.Gas B.Aerosol C.Vapor D.Dust

The correct answer is: C Vapor is an air dispersion of molecules of a substance that is liquid or solid in its normal state at standard temperature and pressure. Vapor is the dispersion of a substance at its most basic level, the molecular level.

One problem associated with flux-cored arc welding of stainless steel is the production of aerosols containing: A.Nickel and chromium B.Carbon and nickel C.Fluorides, nickel, and chromium D.Copper, nickel, and acid gases

The correct answer is: C Welding fumes can contain constituents of the material being welded and the consumable materials (e.g., flux). Stainless steel welding results in fumes containing nickel and chromium. Often flux is used which contain fluorides. These fluorides are also released into the air during the welding process.

When testing or evaluating a ventilation system, a transverse measurement should be taken no less than ___ duct diameters downstream from air disturbances. A.3.5 B.5.0 C.7.5 D.10.0

The correct answer is: C When testing or evaluating a ventilation system, a transverse measurement should be taken no less than 7.5 duct diameters downstream from air disturbances, elbows, hoods, branch entries, etc. This helps to prevent error in the measurement.

MIG (metal inert gas) welding is commonly used when working with: A.Aluminum B.Stainless Steel C.Mild Steel D.Titanium

The correct answer is: C While MIG (metal inert gas) welding is capable of being used for all the listed metals, it is most effective for mild steels. TIG (tungsten inert gas) welding is more effective for aluminum, stainless steel and titanium. Fumes are a concern with both MIG and TIG welding, but MIG welding tends to produce more fumes. All forms of arc welding produce potentially hazardous Ultraviolet (UV) light.

ANSI A13.1 provides a scheme for the identification of piping systems. What standard color is used to identify dangerous materials? A.Red B.Blue-green C.Yellow D.Orange

The correct answer is: C Yellow is the standard color used to identify dangerous materials according to ANSI A 13.1.

Deaths among workers performing quenching operations on metal dross have been caused by acute exposure to: A.Beryllium B.Cadmium C.Lead D.Arsine

The correct answer is: D A dross is a byproduct of a molten metal (it is the residual "scum" that floats to the top of a molten bath and is scooped away). Arsenic is an impurity in many metals and can produce arsine gas which is an extremely toxic gas that causes death with relatively small exposures (the IDLH of arsine is 6 ppm).

Why should acetylene cylinders be stored in an upright position? A.To prevent liquid acetone from escaping B.For proper securing C.In order for the acetylene to work properly D.Both A and B

The correct answer is: D Acetylene cylinders must always be stored in an upright position to allow proper securing and to prevent the liquid acetone solvent from escaping.

Autumn has arrived at a New England office facility and with it, a rash of indoor air complaints. Which HVAC troubleshooting step should you consider performing first? A.Determine if the dampers operate properly B.Check the inside/outside temperature controls C.Determine if the interior air distribution is balanced to specifications D.Check the make-up air ratio, or make-up air damper, to ensure the appropriate seasonal setting is applied

The correct answer is: D During the summer, the office occupants welcome large volumes of air at relatively high velocities. During the cooler months, care must be taken to ensure that air blowing over the occupants is kept within acceptable comfort conditions suitable for the season.

A bleeder valve on a furnace fails after 20,000 days of operation. If the valve operates once per day, what is its failure rate? A.1 x 10^-4 failures/attempt B.5 x 10^-4 failures/attempt C.1 x 10^-5 failures/attempt D.5 x 10^-5 failures/attempt

The correct answer is: D Failure Rate = No. of failures / No. of attempts = 1 failure / 20,000 attempts = 0.00005 = 5 x 10^-5 failures/attempt

Reactive metals are usually arc welded under a shield of inert gas such as argon. Metals that are welded in this manner include aluminum and titanium. The major pollutants from this operation is (are): A.Phosgene B.Ozone C.Ultraviolet light D.Both B and C

The correct answer is: D Metal inert gas (MIG) welding produces relatively little metal fumes. It does, however, produce significant amounts of ultraviolet radiation, and as a secondary pollutant, ozone.

The most common cause of indoor air quality problems is: A.Off-gassing from building materials and furnishings B.Cigarette smoking C.Processes using volatile chemicals D.Poor ventilation

The correct answer is: D Poor ventilation is the most common cause of indoor air quality problems because air contaminants from sources such as cigarette smoke, processes, and off-gassing build-up can cause hypersensitivity in employees. The other answers contribute to the cause, but poor ventilation is usually the root of the problem.

Three half-value layers of which of the following materials will result in the greatest reduction in gamma radiation? A.Lead B.Concrete C.Water D.ANY of the above

The correct answer is: D Since a half-value layer reduces the radiation by one-half, the material is not relevant. Three half-value layers of ANYTHING will result in the same reduction of radiation.

What organization sponsors the major code(s) utilized in the design and construction of pressure vessels in the United States? A.ASME B.API Standard 620 C.NFPA D.Both A and B

The correct answer is: D The two major codes currently in use in the United States are the ASME (American Society of Mechanical Engineers) Code and the API (American Petroleum Institute) Standard 620. An earlier code, discontinued in 1956, was the API-ASME Code

The uniform hazardous waste manifest serves which of the following purposes? A.Certification of treatment/disposal B.Tracking document for delivery to designated TSDF C.Shipping document for hazardous materials per DOT regulations D.Both B and C

The correct answer is: D The uniform hazardous waste manifest serves as both a shipping document and a tracking document. It is the mandatory bill of lading format for hazardous wastes under DOT regulations, and it is the mandatory tracking document under RCRA regulations. The manifest does not serve as a certificate of destruction, nor is it a fail-safe document. Criminals can (and do) manipulate manifests to serve their own purposes.

A CO2 (carbon dioxide) laser has a wavelength in the _______ region. A.Green B.Red C.Ultraviolet D.Infrared

The correct answer is: D The wavelength for a CO2 laser is 10.6 m, is invisible, and can cause retinal damage. This wavelength is in the infrared region of the electromagnetic (EM) spectrum.

Dielectric heaters, high frequency sealers, and diathermy machines are all sources of: A.X-ray radiation B.UV radiation C.IR radiation D.RF radiation

The correct answer is: D These instruments operate within the part of the electromagnetic spectrum labeled as radio-frequency (RF).

Welding that produces ozone will also produce what type of radiation? A.Infrared B.X-ray C.Radio-frequency D.Ultraviolet

The correct answer is: D When performing some types of welding, ultraviolet radiation is produced which coverts oxygen to ozone.

Which of the following is NOT true regarding alarm signals? A.When the subject of the alarm is not stationary, use audible signals. B.When the subject of the alarm is stationary, use visual signals. C.When the message calls for immediate action, use audible signals. D.When the receiving location is noisy, use audible signals.

The correct answer is: D When the receiving location is noisy, audible signals should NOT be used by themselves. Audible alarm signals WITH visual signals should be used in noisy environments.

With what type of "gate" would you connect "heat", "fuel", and "oxygen" to the output "fire"? A.AND B.OR C.Either D.Neither

The correct answer is:A As "heat", AND "fuel", AND "oxygen" are all required for "fire", an "AND" gate is necessary.