Threshold Limit Value - Short Term Exposure Limit (TLV-STEL)

Abbreviated as "TLV-STEL". Refers to a 15 minute time-weighted average exposure which should not be exceeded at any time during a workday even if the time-weighted average is within the TLV. It supplements the 8 hour TLV-TWA for certain substances that produce acute effects on high, short term exposure.