Domain 6 - Occupational Health & Ergonomics
EPA considers the following pollutants "criteria pollutants"
- carbon monoxide - oxides of nitrogen - oxides of sulfur NOT hydrogen sulfide
Ways to evaluate the hazards of gases and vapors:
- collected on an open faced filter and weighed - collected on filter media - collected in containers or absorbed NOT collected on cloth material
Ways to evaluate the hazards of fumes and mists:
- collected on filter media - absorbed on charcoal - collected with a cyclone separator NOT analyzed using fume arrestors
Manual Material Handling tasks can be designed to avoid injuries. Modificaitons to the task may include
- installing handles or hand holds wherever possible - avoiding lopsided weights and loose contents - using hoists or other lift assists when object weight is excessive - keeping loads as close to the body as possible during lift - keeping loads off the floor by using platforms or stands - avoiding twisting, stretching, or leaning with the load - repetitive lifts should be kept between knuckle and shoulder height to reduce bending and reaching
RULA (Rapid Upper Limb Assessment)
- is a postural targeting method for estimating the risks of work-related upper limb disorders. - RULA assessment gives a quick and systematic assessment of the postural risks to a worker. - The analysis can be conducted before and after an intervention to demonstrate that the intervention has worked to lower the risk of injury. - The results of the test is a RULA score. It gives you a fair idea of where you stand with your posture.
Carpal Tunnel Syndrome (CTS)
- occurs when the median nerve becomes pressed or squeezed at the wrist. - usually occurs only in adults - women are 3x more likely than men to develop CTS, likely bc the carpal tunnel itself is smaller in women. The dominant hand is usually affected 1st and more severe. persons with diabetes or other metabolic disorders that directly affect the body's nerves and make them more susceptible to compression are also at high risk. - will NOT result in numbness in the little finger because it's not served by the median nerve.
Workstation ergonomic recommendations
- put monitor directly in front of you and at least 20" away - place monitor so top of line of screen is at or below eye level (downward angle of 15° to center of monitor) - place monitor perpendicular to window
Which frequency of vibration most adversely affects humans?
1 - 125 Hz
While many factors influence ergonomic issues in the workplace, the five PRIMARY ergonomic risk factors include:
1) Force 2) Repetition 3) Posture 4) Vibration 5) Contact stresses
5 classes of immunoglobulins (antibodies)
1. IgG 2. IgA 3. IgM 4. IgE 5. IgD
The maximum exposure to impulsive or impact noise should not exceed:
140 dB peak
What is the maximal whole body lifetime dose of ionizing radiation to a 50 yr old worker allowable under current OSHA and NRC guidelines?
160 rem
A fiber is defined as having an aspect ratio (length to diameter) greater than:
3 to 1
A sound absorption coefficient of 0.6 means that _________ of the sound energy in a wave will be reflected?
40% the "absorption coefficient" is the % of absorption. a sound absorption coefficient of 0.6 means that 40% of the sound energy in the wave will be reflected and 60% absorbed. The key word in the question was reflected, NOT absorbed.
Total dose accumulation equation
5 (N-18) rem; where N=age {190.1096(b)(2)(ii)}
What's the recommended occupational exposure of radiation to the whole body (of non-pregnant individuals) not exceed?
50 mSv per calendar year This is the effective dose averaged over the year. The average effective dose over 5 yrs should not exceed 20 mSv per year.
ACGIH Carcinogen Classifications
A1 - Confirmed human carcinogen A2 - Suspected human carcinogen A3 - Confirmed animal carcinogen with unknown relevance to humans A4 - Not classifiable as a human carcinogen A5 - Not suspected as a human carcinogen ACGIH classifies carcinogens as A1 or A2. Substances for which no human or experimental animal carcinogenic data have been reported are assigned no carcinogenicity designation
Carcinogen categories
A1 - confirmed human carcinogen A2 - suspected human carcinogen A5 - not suspected human carcinogen
RULA action levels
Action Level 1 - score 1-2 indicated that the postures is acceptable if it is not maintained or repeated for long periods. Action Level 2 - score 3-4 indicate that further investigation is needed, and changes may be required. Action Level 3 - scores 5-6 indicate that investigation and changes are required soon Action Level 4 - scores 7-8 indicates that investigation and changes are required immediately
The designation "CIH" is awarded by the:
American Board of Industrial Hygiene (ABIH)
Who accredits industrial hygiene laboratories?
American Industrial Hygiene Association (AIHA)
Biosafety levels
BSL-1: no special precautions BSL-2: lab coat, gloves, eye protection BSL-3: biosafety cabinets to prevent airborne transmission BSL-4: sealed, negative pressure Exhaust air is filtered twice
Bone marrow and eyes are very sensitive to radiation. Damage to the body may be permanent. What other tissue or organ is most sensitive to radiation?
Blood. White blood cells are the most sensitive to radiation, which reduces their number, leaving the body open to infection.
Finklestein's test is used to diagnose: A. Blood lead concentrations B. Epicondylitis C. Carpal tunnel syndrome D. DeQuervain's tenosynovitis
DeQuervain's tenosynovitis - tendonitis originating in the base of the thumb
What meters would be used most often for monitoring weekly exposure to x-rays?
Film Badge & Thermoluminescence detectors (TLD)
Shaver's Disease
From exposure to silica and aluminum dust fumes
Gas Chromotography/Mass Spectrometry (GCMS)
GC/MS is commonly performed to separate and identify compound of interest. - GC separates a mixture based on differences in boiling point and solubility. Differences in these properties produce differences in retention times in the GC column separating the mixture. - MS fractures and ionizes each compound into arecognizable patter.
What's used to detect alpha radiation?
Geiger-Mueller with very thin windows. A Geiger-Mueller detector is used for radiation survey measurement because it's capable of detecting very small amounts of radiation. With very thin windows in the probes, it can be used to detect alpha radiation. Without them, it can detect beta, gamma, and x-rays.
HAZMAT Levels of Protection
Level A - to be selected when the greatest level of skin, respiratory, and eye protection is required. - (full-facepiece SCBA) Level B - the highest level of respiratory protection is necessary but a lesser level of skin protection is needed. - (full-face piece SCBA) Level C - the concentration(s) and type(s) of airborne substances is known and the criteria for using air purifying respirators are met. - (full-face or half-mask air purifying respirators) Level D - a work uniform affording minimal protection: used for nuisance contamination only.
Illumination is defined as the amount of light on a surface from the sun, lamps, or any other light source. The unit of measurement for illumination is:
Lux
Welding
MIG (metal inert gas) welding is commonly used when working with 'mild steel' 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 UV light.
Protection Factor (PF)
PF = outside concentration/inside concentration
Which term describes the age-related tendency to lose sensitivity high-frequency noises.
Presbycusis Most people, especially the young, can hear tones within a range of 16 - 20,000 Hz. A steady loss of hearing occurs as people grow older (i.e. a 60 yr old person often cannot hear sounds with frequencies above 12,000 Hz)
RULA vs REBA
RULA = above waist REBA = entire body
wrist motions
Radial Deviation - the wrist is bent towards the thumb Ulnar Deviation - bend toward the little finger Palmar Flexion - a bend toward the palm Dorsi Flexion - an extension of the wrist towards the back part of the hand
risk-specific dose (RSD)
a dose that corresponds to a specific level of risk to an individual of contracting cancer over a 70-year lifetime due to the intake of contaminated drinking water.
beta particle
a high-speed electron or positron emitted in the decay of a radioactive isotope. if the high speed electron is positively charged the particle is a positron.
Potentiation
a substance which does not have a toxic effect upon a system or organ, but when in combination with another chemical, makes that chemical much more toxic
acclimatization
accomplished in 1 - 2 weeks. significant loss of acclimatization may be seen after 3 days
presbycusis
age related hearing loss
Maximum contaminant level (MCL)
allowable drinking water pollutant concentration under the Safe Drinking Water Act. maximum levels of contaminants allowable in public water systems
alpha emitters
atoms that undergo alpha decay are internal hazards.
Radium target organ
bone for soluble form GI tract for insoluble form
primary reservoir for lead in the body
bones
Raynaud's Syndrome (trigger finger)
closure of the digit's arteries caused by vasospasms triggered by vibrations. Smaller arteries that supply blood to the skin narrow, limiting blood circulation. The fingers and toes are commonly involved feel numb and cool when exposed to cold temps. It's often accompanied by changes in the color of the skin. associated with the use of hand held vibrating tools, results in a loss of feeling and characterized by white spots on the fingers and hands.
which of the following is not a symptom of CTS? a) numbness b) loss of feeling in grip c) loss of hand use and function d) all of the above are symptoms
d
Ionizing radiation is a general term describing charged or uncharged particles that re energetic enough to:
dislodge electrons from the materials they pass through ionizing radiation has the greatest effect on Bone Marrow. The effects of ionizing radiation on body hair is generally temporary after exposure stops.
The magnehelic gauge on a baghouse dust collector is indicating a reading that is 4 inches of water higher than the upper pressure reading specified for the dust collector. The most likely cause of the elevated reading is:
dust is building up on the bags because the reverse pulse system is malfunctioning
Guyon Tunnel Syndrome
entrapment of the ulnar nerve as it passes through the Guyon tunnel in the wrist
Industrial toxicologists use the term dose when describing how individuals response to hazardous material exposures. Dose is defined as:
exposure duration multiplied by exposure concentration
Radiation
five types of radioactivity (ionizing radiation) that are of general concern: 1) Alpha - least penetrating... will not penetrate dead cells on surface of skin. Are considered a critical internal hazard bc may be inadvertently ingested/inhaled/absorbed. 2) Beta - primarily skin exposure. preferred choice of shielding material is Plastic. 3) Gamma - penetrating; whole-body exposure 4) X-ray 5) Neutrons Microwave - form of non-ionizing radiation Infrared - form of non-ionizing radiation
Antigens
foreign substances that trigger the attack of antibodies in the immune response; and found on the surface of microbes. they are either: proteins, polysaccharides, glycoproteins, or nucleoproteins.
Histoplasmosis
fungal infection of the lungs
tendonitis
inflammation of a tendon from repeated tension, motion, bending, being in contact with a hard surface, tension
The human body:
is less capable of coping with heat loss than heat gain
sacrum
located below the lumbar vertebrae. bone formed from five vertebrae fused together near the base of the spinal column
byssinosis
lung disease resulting from inhaling cotton, flax, or hemp, also known as brown lung disease
Radon target organ
lungs for soluble and insoluble forms
Biological Exposure Indices (BEI)
medical sampling determinants for a persons exposure to occupational and non-occupational hazardous chemicals, published by ACGIH. BEI's help to measure an employees' exposure to: occupational benzene, non-occupational benzene, and hazardous gas exposure (NOT Biohazards)
motor end plate
most muscles are joined by hundreds/thousands of nerve fibers of the efferent (motor) nervous system. The contact between the end point of the axon of the motor-neuron and the sarolemma of the muscle is called the motor end plate.
hearing loss
most people can hear sounds between 16 - 20,000 Hz sound between 1,000 - 4,000 Hz frequency is most likely to result in permanent hearing damage; because the ear is most susceptible to noise in the rank that is most sensitive, which is 1,000 - 4,000 Hz. noise induced hearing loss first shows up on an audio-gram between 3,000 - 6,000 Hz.
Maximum Contaminant Level Goal (MCLG)
non-enforceable concentrations of drinking water contaminants that are protective of human health with a margin of safety MCLG's under the Safety Drinking Water Act are non-enforceable health-based standards, and are used in developing legally enforceable MCL's. Aesthetic qualities of drinking water are addressed by non-enforceable secondary MCL's.
components of a virus
nucleic acid capsid envelope NOT a 'cell wall'
Epidemiology
science that deals with frequency and distribution of diseases in a population
why are temperature inversion important in air pollution
serve to concentrate air pollutants near the ground
Food Chain
serves to concentrate heavy metals in the uppermost predators as the lower forms add to their heavy metal loading... the phenomena of 'biomagnification' of heavy metals is due to the food chain.
Deposition of liquid particles in the respiratory system is dependent on
solubility in water
Deposition of solid particles in the respiratory system is dependent on
specific gravity & particle diameter
Replacing a hazardous production chemical with one that poses less risk to a worker is an example of an
substitution control
tenosynovitis
synovial sheath swelling from repetitive motion causing the sheath to press onto the tendon
criteria pollutants
the most pervasive air pollutants and those of greatest concern in the US (particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides, ozone, lead)
Biochemical Oxygen Demand (BOD)
the quantity of oxygen used in the aerobic stabiliation of wastewaters. Amount of oxygen required by aquatic bacteria to decompose given load of organic waste; a measure of water pollution.
safety margin
to calculate safety margin is: K = (minimum strength - maximum stress)/minimum strength
in-vitro
within a glass
in-vivo
within the living