Which OSHA regulatory exposure limit is the maximum allowable concentration over a 40 hour work week?

The permissible exposure limit (PEL) is the correct answer because it represents the maximum concentration of a hazardous substance that a worker can be exposed to over a standard 40-hour workweek. PELs are established by the Occupational Safety and Health Administration (OSHA) to protect workers from health hazards associated with long-term exposure to chemical substances. These limits are designed to prevent adverse health effects that could arise from continuous exposure over the typical duration of a work shift.

In contrast, other terms such as the threshold limit value (TLV) and the action level serve different purposes. TLVs are recommended limits developed by the American Conference of Governmental and Industrial Hygienists (ACGIH) but are not enforceable standards like PELs. The action level refers to a specific concentration that, if exceeded, requires employers to implement certain protective measures, but it is not necessarily the maximum allowable concentration. Short-term exposure limits (STELs) apply to exposure limits over shorter periods, typically 15 minutes, to safeguard against acute effects from occasional spikes in concentration rather than over the standard work week.