What is the OSHA Permissible Exposure Limit (PEL) for lead?

What is the OSHA Permissible Exposure Limit (PEL) for lead?

• A. 150 ug/m3 in an hour period
• B. 100 ug/m3 in an hour period
• C. 50 ug/m3 in an hour period
• D. 50 ug/m3 in an 8-hour time-weighted average

Answer: (C)

The key idea is that OSHA sets lead exposure limits as an average over a full work shift, not for a single hour. The permissible exposure limit for lead is 50 micrograms per cubic meter of air, averaged over an 8-hour time-weighted period. This means you evaluate the worker’s exposure across the entire shift, not just one hour. So the best answer describes 50 µg/m3 over an 8-hour time-weighted average. The other phrasing—50 µg/m3 in an hour or higher hourly limits—doesn’t reflect how the PEL is defined in the standard, which is tied to an 8-hour average. If the 8-hour average approaches or exceeds 50 µg/m3, employers must pursue exposure-reduction measures and related compliance steps.

The key idea is that OSHA sets lead exposure limits as an average over a full work shift, not for a single hour. The permissible exposure limit for lead is 50 micrograms per cubic meter of air, averaged over an 8-hour time-weighted period. This means you evaluate the worker’s exposure across the entire shift, not just one hour.

So the best answer describes 50 µg/m3 over an 8-hour time-weighted average. The other phrasing—50 µg/m3 in an hour or higher hourly limits—doesn’t reflect how the PEL is defined in the standard, which is tied to an 8-hour average. If the 8-hour average approaches or exceeds 50 µg/m3, employers must pursue exposure-reduction measures and related compliance steps.