Consultation on the Occupational Exposure Limit Review Period for Chemical Substances

June 12, 2017

Dear Stakeholder:

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publishes a list of substances for which they have set new or revised Threshold Limit Values (TLVs), retained TLVs, or withdrawn TLVs.

A TLV is an airborne concentration of a chemical substance from which nearly all workers are believed to experience no adverse health effects over a working lifetime. TLVs may be expressed as an 8-hour time-weighted average, a short-term exposure limit, or a ceiling limit.

Before adopting new or revised TLVs published by the ACGIH, WorkSafeBC reviews and consults stakeholders on potential implementation issues. WorkSafeBC’s existing B.C. Occupational Exposure Limits (OELs) continue to be in effect until the Board of Directors makes a decision on which new or revised ACGIH TLVs to adopt as B.C. OELs.

Background information on WorkSafeBC’s OEL review process

WorkSafeBC is requesting stakeholder feedback on a proposed increase to the ACGIH TLV review period from one to three years. A three-year OEL review period provides:

  • Additional time for the development and review of methods to assess worker exposure to new or revised ACGIH TLVs
  • Additional time for industries to prepare and adapt to forthcoming OEL changes
  • Additional time to request and obtain research related to OELs

The Policy, Regulation and Research Division is committed to proactively bringing critical OEL issues to the Board of Directors when warranted prior to the scheduled ACGIH TLV review period. To ensure the ongoing review of new or emerging chemical substance exposure risks, WorkSafeBC’s Risk Analysis Unit also has the mandate to provide ongoing review of potential exposure risks.

Instructions for providing feedback can be accessed via the link below:

Proposed increase to the ACGIH TLV period for B.C. OELs

The deadline for feedback is 4:30 p.m., Friday, September 1, 2017.

All stakeholder feedback received will be carefully reviewed, analyzed, and provided to the Board of Directors of WorkSafeBC to consider as part of their decision making process.


Lori Guiton
Director, Policy, Regulation and Research Division

Please note that COCA will be submitting comments on behalf of members. If you are making a submission on behalf of your own organization or company or would like to provide input to COCA’s response, please email to