PEL stands for permissible exposure limits enforced by the U.S. Occupational Safety and Health Administration, to protect workers against health effects linked to exposure to hazardous substances. PELs can be regulatory limits on the amount of a substance in the air or a concentration limit of a substance in the air and are based on 8-hour time weighted average (TWA) exposure. Learn more about PELs on OSHA.gov.
Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) were developed as guidelines to assist in the control of health hazards in the practice of industrial hygiene. Visit the American Conference of Governmental Industrial Hygienists website for additional information.