At its November 2021 meeting, WorkSafeBC’s Board of Directors (BOD) approved the adoption of the 2016, 2017, and 2018 new and revised American Conference of Governmental Industrial Hygienists Threshold Limit Values (ACGIH TLVs) for the following select chemical substances:

• Chlorine (8-hour TWA only)
• Ethyl isocyanate
• Hard metals, containing cobalt and tungsten carbide, as Co
• Phenyl isocyanate
• Tungsten and compounds in the absence of Cobalt, as W

Effective March 1, 2022, 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:

Due to sampling issues or recent health studies, the BOD decided to not adopt the new or revised ACGIH TLVs for the following substances:

• Atrazine
• Chlorine (15-minute short-term exposure limit only)
• Chlorine dioxide
• Chromium and inorganic compounds:
  • Metallic chromium, as Cr(0), total, previously known as “Chromium, Metal, total”
  • Trivalent chromium compounds, as Cr(III), total, previously known as “Chromium, Cr(III) compounds, total”
  • Hexavalent chromium compounds, as Cr(VI), total, insoluble, previously known as “Chromium, insoluble, Cr(VI) compounds, total”
  • Hexavalent chromium compounds, as Cr(VI), total, water-soluble, previously known as “Chromium, water-soluble, Cr(VI) compounds, total”
  • Chromyl chloride, as Cr(VI), total, previously known as “Chromyl chloride, total”
  • Calcium chromate, as Cr
  • Strontium chromate, as Cr
  • Zinc chromates, as Cr
• Ethylene glycol
• Ethylidene norbornene
• Glycerin mist
• Hexylene glycol
• Phosphine

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.

For chlorine, the BOD adopted the ACGIH TLV of 0.1 ppm (8-hour exposure limit), but did not adopt the ACGIH TLV of 0.4 ppm (15-minute Short-term exposure limit) as a B.C. exposure limit due to sampling issues (as noted above).

Effective March 1, 2022, Chlorine will be reflected in the Table of Exposure Limits for Excluded Substances in Policy R5.48-1 of the Prevention Manual as B.C. exposure limits as follows:

The ACGIH has aligned the TLVs for the following substances with the existing TLVs for Trivalent chromium compounds, as Cr(III); Hexavalent chromium compounds, as Cr(VI); and Lead and inorganic compounds, as Pb:

• Chromite ore processing, previously known as “Chromite ore processing (chromate)” and “Chromite ore processing (chromate), as Cr, total”
• Lead chromate, as Cr(VI), total, previously known as “Lead chromate, as Cr, total”
• Lead chromate, as Pb

Therefore, the aforementioned substances will now be aligned with the existing B.C. exposure limits for Trivalent chromium compounds, as Cr(III); Hexavalent chromium compounds, as Cr(VI); and Lead and inorganic compounds, as Pb.

Effective March 1, 2022, Chromite ore processing; Lead chromate, as Cr(VI), total; and Lead chromate, as Pb will be reflected in the Table of Exposure Limits for Excluded Substances in Policy R5.48-1 of the Prevention Manual as B.C. exposure limits as follows:

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.