Industrial hygiene is the science of anticipating, recognizing, evaluating, and controlling workplace conditions that may cause workers’ injury or illness.
The history of Industrial Hygiene recognizes that as early as the fourth century B.C., Hippocrates noted the toxicity of lead in mining and the Roman scholar, Pliny, noted the health hazards of zinc and sulfur. In the early 20th century in the U. S., Dr. Alice Hamilton, observed industrial conditions first hand noted a correlation between worker illness and their exposure to toxins. The American Conference of Governmental Industrial Hygienists (ACGIH) traces its origins to 1938. The Industrial Hygienists in ACGIH started to establish the Threshold Limit Values (TLV’s) for chemicals. In establishing a TLV, it is assumed that the human body can detoxify chemicals until a certain amount overwhelms the bodies system. This is referred to as the threshold level. Above this threshold level the chemical will be toxic to the person. The ACGIH annually republishes the TLV’s for 642 chemical substances.
In 1970, OSHA adopted the ACGIH TLV’s of 1969 and designated them as the OSHA Permissible Exposure Levels (PEL’s). Today, nearly every employer is required to implement the elements of an industrial hygiene and safety, occupational health, or hazard communication program and to be responsive to the Occupational Safety and Health Administration (OSHA) Act and its regulations.
A worksite analysis is an essential first step that helps an industrial hygienist determine what jobs are the sources of potential problems. During the worksite analysis, the industrial hygienist measures and identifies exposures, problem tasks, and risks. The most effective worksite analyses include all jobs, operations, and work activities. The industrial hygienist inspects, researches, or analyzes how the particular chemicals or physical hazards at that worksite affect worker health.
How we control hazards
Engineering, work practice, and administrative controls are the primary means of reducing employee exposure to occupational hazards.
Engineering controls minimize employee exposure by either reducing or removing the hazard at the source or isolating the worker from the hazards.
Engineering controls include eliminating toxic chemicals and replacing harmful toxic materials with less hazardous ones, enclosing work processes or confining work operations, and installing general and local ventilation systems.
Work practice controls alter the manner in which a task is performed. Some fundamental and easily implemented work practice controls include:
(1) Following proper procedures that minimize exposures while operating production and control equipment;
(2) Inspecting and maintaining process and control equipment on a regular basis;
(3) Implementing good house-keeping procedures;
(4) Providing good supervision and
(5) Mandating that eating, drinking, smoking, chewing tobacco or gum, and applying cosmetics in regulated areas be prohibited.
Administrative controls include controlling employees’ exposure by scheduling production and workers’ tasks, or both, in ways that minimize exposure levels. For example, the employer might schedule operations with the highest exposure potential during periods when the fewest employees are present.
When effective work practices and/or engineering controls are not feasible to achieve the permissible exposure limit, or while such controls are being instituted, and in emergencies, appropriate respiratory equipment must be used. In addition, personal protective equipment such as gloves, safety goggles, helmets, safety shoes, and protective clothing may also be required. To be effective, personal protective equipment must be individually selected, properly fitted and periodically refitted; conscientiously and properly worn; regularly maintained; and replaced as necessary.