Workplace Hazardous Materials Information System (WHMIS) requires that two types of labels be used in hazard communication: supplier labels and workplace labels.

Supplier labels are meant for controlled products manufactured in Canada or imported for use in Canada. These labels must be affixed on drums, pails, bottles and other containers. Precise specifications for supplier labels include a distinctive border, symbols for each hazard class, and the information contained must be in a strict format.

Workplace labels are meant for controlled products produced at the workplace and used at the workplace. Workplace labels can replace supplier labels if they have been removed or have become impossible to read. There are no specific graphic formats but vital hazard information is required by law. HMI-ES labels can be substituted for WHMIS workplace labels.