Decision on the New and Revised B.C. Exposure Limits based on the 2019 and 2020 ACGIH TLVs for Selected Chemical Substances
At its April 2023 meeting, WorkSafeBC's Board of Directors (BOD) approved the adoption of the 2019 and 2020 new and revised American Conference of Governmental Industrial Hygienists Threshold Limit Values (ACGIH TLVs) for the following selected chemical substances:
- Cyclohexene
- Methyl isobutyl carbinol
Effective June 6, 2023, these substances will be removed from the Table of Exposure Limits for Excluded Substances in Policy R5.48-1 of the Prevention Manual and the ACGIH TLVs will be assigned as B.C. exposure limits:
|
Substance |
B.C. exposure limits |
||
|---|---|---|---|
|
8-hour time-weighted average limit |
Short-term exposure limit |
Ceiling limit |
|
|
Cyclohexene |
20 ppm |
--- |
--- |
|
Methyl isobutyl carbinol |
20 ppm |
40 ppm |
--- |
Due to sampling issues, the BOD decided to not adopt the new or revised ACGIH TLVs for the following substances:
- Cyanazine
- Hexazinone
- Sulfoxaflor
- Temephos
- Thiacloprid
- 4-tert-Butylbenzoic acid
- Chlordane
- o-Chlorobenzylidene malononitrile
- Dimethylphenol, all isomers
- Dinitrobenzene, all isomers
- Dinitro-o-cresol
- EPN
- 4,4'-Methylene bis(2-chloroaniline)
- Nitrapyrin
- 5-Nitro-o-toluidine
- Pentachloronaphthalene
- Sulfometuron methyl
- Tetramethyl succinonitrile
- Thiodicarb
- 2,4,6-Trinitrotoluene
For these substances, the existing exposure limits will be maintained on the Table of Exposure Limits for Excluded Substances in Policy R5.48-1 of the Prevention Manual.
WorkSafeBC will continue to monitor the availability of sampling methods for all of these substances, as well as to work on ongoing initiatives to develop, validate, and implement sampling methods.