Glossary
Action Level
The exposure threshold that triggers OSHA's requirements for medical surveillance, exposure monitoring, and training, set below the permissible exposure limit.
The action level is a substance-specific exposure concentration, set below the PEL, that triggers OSHA’s requirements for medical surveillance, exposure monitoring, and training.
For asbestos under 29 CFR 1926.1101, the action level is 0.1 fibers per cubic centimeter of air as an 8-hour time-weighted average. For lead under 29 CFR 1926.62, the action level is 30 micrograms per cubic meter of air as an 8-hour TWA.
Crossing the action level is the trigger, not the violation. The PEL is the violation threshold. Exposures at or above the action level for more than 30 days in any consecutive 12 months bring the worker into the medical-surveillance program for the substance.