Each year, the American Conference of Governmental Industrial Hygienists (ACGIH) publishes a list of substances for which they have set new or revised Threshold Limit Values (TLVs). A TLV is an airborne concentration of a chemical substance where it is believed that nearly all workers may be exposed over a working lifetime and experience no adverse health effects. TLVs may be expressed as an 8-hour time-weighted average (TWA), 15-minute short-term exposure limit (STEL), or ceiling limit.
Prior to the adoption of new or revised TLVs published by the ACGIH, WorkSafeBC reviews relevant data on health effects and the availability of validated sampling methods. WorkSafeBC also consults with stakeholders on potential implementation issues. WorkSafeBC’s existing B.C. Exposure Limits (ELs) continue to be in effect until the Board of Directors decides which new or revised ACGIH TLVs to adopt as B.C. ELs.
WorkSafeBC is requesting stakeholder feedback on the proposed ELs for 22 substances.
(1) WorkSafeBC is proposing new or revised B.C. ELs for the following substances:
- Chlorine (8-hour TWA only)
- Ethyl isocyanate
- Phenyl isocyanate
- Hard metals, containing Cobalt and Tungsten carbide, as Co
- Tungsten and compounds in the absence of Cobalt, as W
(2) WorkSafeBC is proposing to retain the existing B.C. ELs for the following substances:
- Chlorine (15-minute STEL only)
- Chlorine dioxide
- Chromium and inorganic compounds:
• Metallic Chromium, as Cr(0)
• Trivalent Chromium Compounds, as Cr(III)
• Hexavalent Chromium Compounds, as Cr(VI)
• Chromyl chloride
• Calcium chromate, Cr
• Strontium chromate, as Cr
• Zinc chromates, as Cr
- Ethylene glycol
- Ethylidene norbornene
- Glycerin mist
- Hexylene glycol
(3) WorkSafeBC is proposing to update the existing B.C. ELs for the following substances to align with other existing B.C. ELs:
- Chromite ore processing
- Lead chromate, as Cr(VI)
- Lead chromate, as Pb
Feedback will be accepted until 4:30 p.m., Friday, August 13, 2020.