The permissible exposure limit (PEL or OSHA PEL) is a legal limit in the United States for exposure of an employee to a chemical substance or physical agent such as high level noise.
Permissible exposure limits were established by the Occupational Safety and Health Administration (OSHA).
Most of OSHA's PELs were issued shortly after adoption of the Occupational Safety and Health (OSH) Act in 1970.
"[3] Excursion limits are enforced in some states (for example Oregon) and on the federal level for certain contaminants such as asbestos.
A ceiling limit is one that may not be exceeded for any time, and is applied to irritants and other materials that have immediate effects.
OSHA requires feasible engineering OR administrative controls, and mandatory hearing protection when the PEL is exceeded.
Like OSHA, Mine Safety and Health Administration (MSHA) also uses the same 5 decibel exchange rate and 90 dBA for an 8-hour TWA for their PEL.
[11][10] Permissible Exposure Limits are time-weighted average, meaning that a worker may be exposed to higher concentrations of the chemical at different times of the work shift.
[16] For worker's safety, OSHA mandates hearing conservation programs when noise levels are higher than 85 decibels.
One way to limit noise exposure is by wearing personal protective equipment (PPE) such as earplugs, or earmuffs.