Designated Substances

The Ministry of Labour (MOL) has designated twelve Regulations for specific substances due to their toxicity and/or carcinogenic properties.  The Occupational Health and Safety Act (OHSA) defines a Designated Substance as:

  a biological, chemical or physical agent or combination thereof prescribed as a designated substance                                     to which the exposure of a worker is prohibited, regulated, restricted, limited or controlled.

The following materials have been rated as Designated Substances and are covered under Regulation 490/09:

The Act ensures that workers exposure is controlled, toxic substances in the workplace are clearly identified and the worker's receive sufficient information to handle toxic substances safely.  The Regulations apply to all individuals and contractors who process, use, handle or store Designated Substances in McMaster University owned facilites, areas in host institutions occupied by McMaster University staff and students or in the field.

For further information regarding the Designated Substances Regulations, please refer to the Ministry of Labour website.  Additional information may be found in the McMaster University Risk Management Manual #500 Designated Substances Control Program.

Once a Designated Substance is present in the workplace in order for the University to comply with the Act, McMaster University is required to maintain an inventory of all Designated Substances.

If you are using chemicals classified as Designated Substances, please complete an assessment form Word Document.  The Designated Substances assessment must be reviewed by your local Joint Health and Safety Committee (JHSC).  In addition, a copy of the assessment must be reserved in the area containing the Designated Substance, and a copy of the assessment must be sent to Environmental and Occupational Health Support Services (EOHSS).

Please note, if modifications are made to the process, use, handling and/or storage of Designated Substances, the assessment must be updated and reviewed with the local JHSC.

Please send all assessments to EOHSS as we maintain an inventory of all Designated Substances used at McMaster University.  Please submit your copies to EOHSS in Gilmour Hall Room 304 or electronically to .