Safety usually associated with acute injuries, short-term, traumatic exposures.
Health usually directed at chronic exposures, persistent, prolonged, repeated.
Industrial Hygiene - "that science and art devoted to the anticipation, recognition, evaluation, and control of those environmental factors or stresses, arising in or from the workplace, which may cause sickness, impaired health and wellbeing, or significant discomfort, and inefficiency among workers or among the citizens of the community"
Chemical - environmental concentrations
Physical - noise, heat, ionizing, etc.
Ergonomic - man-machine interface
Biological - micro living organisms
Solids - definite shape and volume
Liquids - definite volume but no definite shape
Gases - neither definite volume nor shape
Figure: Chemical Stresses Chart (available in full paper)
Dusts - solid particles from handling, grinding, rushing, impact (1–25 microns) (cotton, grain, grinding wheels)
Smoke - carbon or soot particles less than .1 microns in size and are the products of incomplete combustion (fire, gas engines)
Fumes - solid particles generated by condensation from the gaseous state (welding, soldering, brazing)
Aerosols - solid particles or liquid droplets of fine enough size to remain dispersed in air for a prolonged period of time (powder sprays, paint sprays)
Mists - suspended liquid droplets generated by condensation of liquids, or by breaking up a liquid into a dispersed state (mixing vats, maintenance degreasers)
Vapors - volatile form of a substance normally a liquid or solid at STP(paint thinners, nail polish remover)
TLV - threshold limit value - airborne concentration under which it is believed that nearly all workers may be repeatedly exposed day after day without adverse effect (ACGIH)
PEL - permissible exposure limit (OSHA)
TWA - time weighted average - average exposure over a workday
C - ceiling - level not to be exceeded at any time
STEL - short term exposure limit (15 minute exposure not producing harm)
REL - recommended exposure limit, NIOSH term to designate agency's maximum concentration
BEI - biological exposure index; advisory levels adopted for some substances by ACGIH based on blood, urine, or expired air - TLV-TWA for eight hours
ppm - parts per million
mg/m3 - milligrams per cubic meter
Inhalation - breathing, most common
Ingestion - swallowing
Absorption - penetration through the skin
Injection - forcing by mechanical means
Concentration of substance
Probability of substance to produce injury
Rate of generation of material
Control measures
Capacity of a material to produce injury or harm; Depends on dose, rate, method, site of entry, general health of individual, diet, temperature
Irritants - inflame surfaces of the body
Systemic poisons - attack organs or system
Depressants - affect the central nervous system
Asphyxiants - prevent oxygen from reaching body cells (simple - nitrogen; chemical - carbon monoxide)
Carcinogens - cancer causing (benzene)
Teratogens - affect the fetus (lead)
Mutagens - affect the species (radiation)
Noise
Temperature extremes
Ionizing radiation
Non-ionizing radiation
Noise -
