The Workplace Hazardous Materials Information System (WHMIS) is Canada’s national standard for communicating information about hazardous workplace products. It is implemented through complementary federal, provincial and territorial laws. Originally established in 1988, the purpose of WHMIS is to ensure employers and workers receive consistent and comprehensive health and safety information about the hazardous products they may be exposed to at work. By setting standards for the type and amount of information to be given to the users of hazardous chemicals and biological agents, WHMIS is intended to reduce workplace injuries and illnesses related to such products.

The main elements of WHMIS are:

Product classification
Products intended for use in the workplace are classified based on their hazardous properties.
Labels
Provide basic information that a worker needs to know to safely use a hazardous product.
Safety data sheets (SDSs)
Supplement the label with more detailed information about a product’s physical and chemical characteristics, its hazardous properties and necessary handling precautions.
Worker education
Ensures workers understand the information on labels and safety data sheets and can apply this knowledge on the job.

This guide is intended to give workplace parties a basic understanding of WHMIS and to direct readers to more detailed information, if needed.

This guide does not replace the Occupational Health and Safety Act (OHSA) and its regulations, and should not be used as or considered legal advice. Health and safety inspectors apply the law based on the facts in the workplace.