Prevention System Updates

MOL proposes changes to occupational exposure limits

Release Date:  Jan 28, 2013

Ontario’s Ministry of Labour has proposed new or revised occupational exposure limits (OELs) for nine hazardous chemicals listed under the Occupational Health and Safety Act. The list includes:

  • five new substances - allyl bromide, carbonyl sulfide, diacetyl, o-phthalodinitrile, and piperazine and its salts
  • revisions to exposure limits or listings for 3 substances currently regulated — ethyl formate, nitrogen dioxide and nonane.

The ministry also proposes withdrawing the listing and specific exposure limit for piperazine dihydrochloride, and regulating it under the new listing for piperazine and its salts.

OELs restrict the amount and duration of worker exposure to specific hazardous workplace substances. Ontario has updated OELs for 200 hazardous substances since 2004. These limits are based on recommendations by the American Conference of Governmental Industrial Hygienists (ACGIH).

The ministry invites public comment on the proposed changes. For more information, visit the ministry’s web page.