At the May 2018 meeting, the Board of Directors (BOD) approved the adoption of the 2013, 2014, and 2015 new and revised American Conference of Governmental Industrial Hygienists Threshold Limit Values (ACGIH TLVs).

The BOD decided to adopt the ACGIH TLVs as BC OELs for the following substances:

• Acetone;
• Aliphatic hydrocarbon gases, Alkanes [C1 – C4];
• Barium sulfate;
• 1-Bromopropane;
• Butane, Isomers;
  • n-butane;
  • isobutane;
• Ethyl tert-butyl ether;
• 1-Methoxy-2-propanol;
• Methyl formate;
• Methyl isoamyl ketone;
• Methyl isocyanate;
• Naphthalene;
• Oxalic acid, anhydrous;
• Oxalic acid, dihydrate;
• Pentane, all isomers;
• Trichloroacetic acid;
• Triethylamine.

Effective June 1, 2018, these substances will be removed from the Table of OELs for Excluded Substances in Policy R5.48-1, and the ACGIH TLVs will be assigned as BC OELs as follows:

Associated ACGIH notations will be retained and updated for the respective individual aliphatic hydrocarbon gases (e.g. methane, ethane, propane). Butane, isomers will also have its own exposure limit. The updated Convenience Table will reflect the respective substances’ hazards as being a simple asphyxiant and/or an explosion hazard.

The BOD decided to maintain the existing exposure limits for the following substances due to sampling and/or implementation issues:

• Atrazine;
• Clopidol;
• Cyanogen bromide;
• 2,4 – Dichlorophenoxyacetic acid and its esters;
• Diethylene glycol monobutyl ether;
• N,N – Diethylhydroxylamine;
• Ethyl Isocyanate;
• Ethylidene norbornene;
• Glycerin mist;
• Lithium hydride;
• Methomyl;
• Pentachlorophenol;
• Peracetic acid;
• Phenyl isocyanate;
• Tributyl phosphate;
• 1,2,3-Trichloropropane.

For Manganese, elemental and inorganic compounds, as Mn, the BOD decided to maintain the existing 8-hour exposure limit of 0.2 mg/m³ (“total” dust), and adopt the ACGIH TLV of 0.02 mg/m³ (“respirable” fraction) as BC OELs. The BOD decided not to adopt the ACGIH TLV for manganese (“inhalable” fraction) as a BC OEL due to sampling issues.

For Nickel carbonyl, as Ni, the BOD decided to maintain the existing exposure limit of 0.001 ppm (8-hour TWA Limit), and adopt the ACGIH TLV of 0.05 ppm (Ceiling Limit) as BC OELs.

Effective June 1, 2018, these substances will be reflected in the Table of OELs for Excluded Substances in Policy R5.48-1, and will be assigned as BC OELs as follows:

WorkSafeBC will continue to monitor the availability of sampling methods for all of these substances.