December 19, 2011


The Ontario Ministry of Labour (MOL) is seeking input on the proposed changes to the occupational exposure limits (OELs) of nine hazardous chemical substances that are set out in Regulation 883 – Control of Exposure to Biological or Chemical Agents.


The MOL is considering adopting the changes recommended by the American Conference of Governmental Industrial Hygienists (ACGIH). Proposed changes for the substances listed below may include a reduction in OEL or changes in particle size fraction. This could impact sampling and analytical methods used by industry.The proposed substances are:


Acetic anhydride [108-24-7]
Allyl chloride [107-05-1] – Skin
Carbon black [1333-86-4]
Ethyl benzene [100-41-4]
Maleic anhydride [108-31-6]
Methyl isopropyl ketone [563-80-4]
2,4-Pentanedione [123-54-6] – Skin
4,4’-Thiobis(6-tert-butyl-m-cresol) [96-69-5]


Click here for the full press release, including information on how to submit input to the MOL.