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Industrial Hygiene
Industrial hygiene is defined as the recognition, evaluation, and control of workplace hazards.
Its origins are based on limiting personal exposures to chemicals, and have evolved to address the control of most other workplace hazards including over-exposure to noise, heat, vibration, and repetitive motion
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OSH Act of 1970 The purpose of the OSH Act is to
“assure so far as possible every working,
man and woman in the nation safe and
healthful working conditions and to
preserve our human resources.”
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Environmental Factors or StressesChemical hazards
gases, vapors, dusts, fumes, mists, and smoke
Physical hazards
radiation, noise, vibration, extreme temperatures and pressures
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Environmental Factors or StressesErgonomic hazards
workstation design, repetitive motion, improper lifting/reaching, poor visual conditions
Biological hazards
insects, mold, fungi, bacteria, and viruses
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Routes of EntryInhalation
airborne contaminants
Absorption
penetration through the skin
Ingestion
eating
drinking
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OSHA Hierarchy of ControlEngineering controls
Work practice controls
Administrative controls
Personal protective equipment (PPE)
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Types of ExposureAcute
Short term period between exposure and onset of symptoms
ChronicLong time period between exposure to an
agent and the onset of symptoms
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Types of Air ContaminantsParticulates
dusts, fumes, mists, and fibers
non respirable particles
> 10 m in diameter
respirable particles
< 10 m in diameter
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Types of Air ContaminantsFumes
volatilized solids condenses in cool air < 1.0 m in diameter
hot vapor + air (reaction with) = oxideMists
suspended solid dropletsgenerated by a condensation of liquids from a
vapors to a liquid state
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Types of Air ContaminantsFibers
solid, slender, elongated structureslength several times the diameter
Gasesformless fluids that expand to occupy a space
arc-welding, internal combustion engine exhaust air
Vaporsliquid changed to vapor
organic solvents
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Hearing Conservation ProgramMandatory
at an 8-hour TWA > 85 dBA
Exposure monitoring
Audiometric testing
Hearing protection
Employee training
Recordkeeping
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ProtectionThe selection of appropriate
personal protective equipment for exposure control often requires both an understanding of the limitations of the equipment, and the expected exposure parameters as determined by an industrial hygiene evaluation. Engineering controls are considered the preferred method of control, but personal protective equipment plays an important role for health, safety, and rescue. The potential for misuse or misapplication of these devices should be evaluated. 13
Industrial Hygiene
ANTICIPATION RECOGNITION EVALUTION CONTROL
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