Ontario currently has Occupational Exposure Limits (OELs) for over 725 hazardous chemical substances.

OELs are based on the 1985 limits recommended by the American Conference of Governmental Industrial Hygienists (ACGIH).

The 2008 consultation will be the fifth review under the ministry's process to keep OELs up-to-date. Commencing today, a 60-day consultation for changes to 2008 limits will be launched.

New or revised OELs and listings are proposed for 21 substances (see table). The changes include:

• Proposed OELs for two substances not previously listed in Ontario regulations:
  • Butenes, all isomers and Isobutene
  • Polyvinyl chloride (PVC)
• Consolidation of the following four separate listings for aluminum and its compounds into one listing for aluminum metal and insoluble compounds:
  • Aluminum - powder
  • Alpha-Alumina (total dust)
  • Aluminum, metal and oxide dust
  • Emery (total dust)
• The withdrawal of following three listings due to ACGIH's determination of insufficient data to support the OEL:
  • Aluminum, alkyl derivatives of
  • Aluminum, water-soluble compounds of
  • Triphenyl amine
• The withdrawal of separate exposure limits for welding fume:
  • Worker exposure to aluminum-containing fume will be regulated by the OEL for aluminum metal and insoluble compounds.
  • Worker exposure to iron-containing fume will be regulated by the OEL for iron oxide (Fe₂0₃)
  • Worker exposure to welding fume, not otherwise classified, will be regulated as Particles (insoluble or poorly soluble) Not Otherwise Specified (PNOS)
  • Revised exposure limits or listings for another 11 substances.
• The development of an OEL for a specific particle size fraction for seven substances previously regulated.

Stakeholders are invited to submit comments to the ministry on any or all of the proposed OEL changes and to nominate substances for development of an OEL where ACGIH does not list a recommended exposure limit for that substance and does not have one under development.

Once the consultation closes on September 18, 2008, MOL staff review stakeholder submissions and hold focussed meetings with concerned stakeholders, as necessary. Based on consideration and analysis of feedback from stakeholders, MOL develops recommendations for ministerial approval concerning appropriate exposure limits for the proposed substances.

Comments should be sent in writing by September 18, 2008 to:

The OEL Update Project
Ontario Ministry of Labour
400 University Ave., 12th Fl.
Toronto, ON M7A 1T7
Fax: 416-326-7650
Phone: 416-326-9299
E-mail: oelupdateproject@Ontario.ca