Which limit specifies maximum exposure for 15 minutes with rest between exposures?

Which limit specifies maximum exposure for 15 minutes with rest between exposures?

• A. TLV/TWA
• B. TLV/C
• C. TLV/STEL
• D. PEL

Answer: (C)

Short-term exposure limit (STEL) sets the maximum concentration a worker can be exposed to for a brief period, typically 15 minutes, with a rest period between such exposures. This allows for brief peak exposures without causing cumulative harm, so there’s usually a required recovery time (often about 60 minutes) between exposures. That’s why this item points to the TLV/STEL concept. Other limits serve different purposes: TLV/TWA is the average over a full shift, TLV/Ceiling is an instantaneous limit that should never be exceeded, and PEL is the regulatory exposure limit set by OSHA.

Short-term exposure limit (STEL) sets the maximum concentration a worker can be exposed to for a brief period, typically 15 minutes, with a rest period between such exposures. This allows for brief peak exposures without causing cumulative harm, so there’s usually a required recovery time (often about 60 minutes) between exposures. That’s why this item points to the TLV/STEL concept. Other limits serve different purposes: TLV/TWA is the average over a full shift, TLV/Ceiling is an instantaneous limit that should never be exceeded, and PEL is the regulatory exposure limit set by OSHA.