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Consultation on Proposed Occupational Exposure Limits based on the New or Revised 2016, 2017, and 2018 ACGIH TLVs for Selected Chemical Substances

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 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 (TWA), short-term exposure limit (STEL) or ceiling limit.

Prior to the adoption of new or revised TLVs published by the ACGIH, WorkSafeBC reviews and consults with 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.

WorkSafeBC is requesting stakeholder feedback on the proposed OELs for 31 substances.

(1) WorkSafeBC proposes new or revised OELs for the following substances:

Boron trifluoride (8-hour TWA only)
Calcium silicate, naturally occurring as Wollastonite
Calcium silicate - Synthetic nonfibrous
Liquefied Petroleum Gas (L.P.G.)
Styrene, monomer

(2) WorkSafeBC proposes to retain the existing OELs for the following substances:

Boron tribromide
Boron trichloride
Boron trifluoride (ceiling limit only)
2,4-Dichlorophenoxyacetic acid (2,4-D)
Furfuryl alcohol
Phthalic anhydride
Toluene diisocyanate, 2,4- or 2,6- (or as a mixture)
  • Toluene-2,4-diisocyanate (2,4-TDI)
  • Toluene-2,6-diisocyanate (2,6-TDI)
Triorthocresyl phosphate

(3) For hazard communication purposes, WorkSafeBC has automatically adopted new or revised ACGIH notations of “simple asphyxiant” and “explosion hazard” for the following substances:

Butane, isomers
Methyl acetylene
Methyl acetylene-propadiene mixture (MAPP)
Natural Gas

Providing feedback

Feedback can be provided online or via email, fax or mail as follows:

Online feedback: Consultation is now closed
Fax: 604.279.7599
or toll-free in B.C. 1.877.279.7599
Mail: Policy, Regulation and Research Division
P.O. Box 5350, Station Terminal
Vancouver BC V6B 5L5

Feedback will be accepted until 4:30 p.m., Friday, September 27, 2019.

Please include the following information in your comments:

  • Your name;
  • Whether you are submitting on your own behalf or on behalf of an organization (if on behalf of an organization, please specify the name of the organization);
  • Whether you are commenting from a worker’s perspective or an employer’s perspective;
  • Your level of support for the adoption of the proposed new or revised OELs, retention of OELs, and OEL withdrawal - whether you generally agree, are generally neutral, or generally disagree; and,
  • The reasons for your level of support for the substances you are commenting on.

WorkSafeBC will send you an acknowledgement of receipt of your feedback.

Please be advised that stakeholders will not be contacted regarding their feedback unless clarification is needed.

Online feedback option

To provide online feedback please click and open the hyperlink for the proposed OELs. Once opened, please click on the yellow "Online Feedback" button to provide your feedback.

Publication and disclosure of personal information

Please note that all comments become part of the Policy, Regulation and Research Division’s database and may be published, including the identity of organizations and those participating on behalf of organizations. The identity of those who have participated on their own behalf will be kept confidential according to the provisions of the Freedom of Information and Protection of Privacy Act. Publication by WorkSafeBC does not mean WorkSafeBC endorses the view(s) of the person making the submission.