Threshold limit value-time-weighted average TLV-TWA

Threshold Limit Value-Time Weighted Average (TLV-TWA) The time-weighted arerage concentration for a coinentioiial 8-hour workday and a 40-hour workweek, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect,... 

Class A signifies refrigerants for which toxicity has not been identified at concentrations less than or equal to 400 ppm, based on data used to determine Threshold Limit Value-Time Weighted Average (TLV-TWA) or consistent indices from Section 6.1.2. ... 

Short-Term Exposure Limit (STEL)—The American Conference of Governmental Industrial Hygienists (ACGIH) maximum concentration to which workers can be exposed for up to 15 min continually. No more than four excursions are allowed per day, and there must be at least 60 min between exposure periods. The daily Threshold Limit Value - Time Weighted Average (TLV-TWA) may not be exceeded. 

There are three biological exposure indices (BEls) for exposure to trichloroethylene at the ACGIH threshold limit value time-weighted average (TLV-TWA) of 50 ppm (ACGIH 1996). When measured at the end of a 40-hour workweek, TCA in urine is approximately 100 mg/g creatinine when measured at the end of an 8-hour shift at the end of a workweek TCA and trichloroethanol in urine is approximately 300 mg/g creatinine, and free trichloroethanol in blood is approximately 4 mg/L. 

Acetic acid was not clastogenic in Chinese hamster ovary (CHO) cells in vitro when the pH of the culture medium was neutralized. The 2003 ACGIH threshold limit value-time-weighted average (TLV-TWA) for acetic acid is 10 ppm (25mg/m ) with a short-term exposure limit of 15 ppm (37mg/m ). 

The 2003 ACGIFI threshold limit value-time-weighted average (TLV-TWA) for aldrin is 0.25mg/m with a notation for skin absorption. 

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