At the December 2019 meeting, the 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:

• Calcium silicate, naturally occurring as Wollastonite;
• Calcium silicate – Synthetic nonfibrous;
• Formaldehyde;
• Furfural;
• Liquefied Petroleum Gas (L.P.G.);
• Styrene, Monomer.

Effective January 6, 2020, these substances will be removed from the Table of ELs for Excluded Substances in Policy R5.48-1, and the ACGIH TLVs will be assigned as BC ELs:

Associated ACGIH notations of “simple asphyxiant” and/or “explosion hazard” have been adopted for the following substances:

Butane, isomers; Methyl acetylene; and Methyl acetylene-propadiene mixture (MAPP) will also maintain their existing BC exposure limits. The updated Convenience Table (https://www.worksafebc.com/en/law-policy/occupational-health-safety/searchable-ohs-regulation/ohs-guidelines/guidelines-part-05#EL_Table) will reflect the respective substances’ hazards as being a simple asphyxiant and/or an explosion hazard.

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

• Acetamide;
• Boron tribromide;
• Boron trichloride;
• Cadusafos;
• Captafol;
• Cyanogen;
• 2,4-Dichlorophenoxyacetic acid (2,4,-D);
• Folpet;
• Furfuryl alcohol;
• Phthalic anhydride;
• Propoxur;
• Simazine;
• 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;
• Warfarin.

For these substances, the existing exposure limits will be maintained on the Table of ELs for Excluded Substances in Policy R5.48-1.

For Boron trifluoride, the BOD adopted the ACGIH TLV of 0.1 ppm (8-hour exposure limit), but maintained the existing exposure limit of 1 ppm (Ceiling Limit) as BC ELs due to sampling issues.

Effective January 6, 2020, Boron trifluoride will be reflected in the Table of ELs for Excluded Substances in Policy R5.48-1 as BC ELs 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.