Employer obligations under WHMIS: a practical guide for Canadian organizations
Maintaining SDS libraries, ensuring proper labelling, delivering workplace-specific training, and keeping accurate records — a practical walkthrough of what WHMIS actually requires from Canadian employers.
Key takeaways
- Under WHMIS, every Canadian employer whose workers use, handle, store or may be exposed to a hazardous product must meet five ongoing obligations: label every hazardous product, keep a current SDS readily accessible for each one, educate and train workers, set workplace-specific safe-work and emergency procedures, and review the program regularly.
- Suppliers classify products and provide labels and SDS; once a product enters the workplace, responsibility for labelling, SDS access and training passes to the employer.
- WHMIS training must cover the specific hazardous products and procedures of that workplace. A generic online course alone does not satisfy the employer's legal obligation.
- Workers who only may be exposed — cleaners, maintenance staff, supervisors, temporary workers and contractors — need WHMIS training too, and the host employer is responsible for it, not the staffing agency.
- Enforcement is split: Health Canada regulates suppliers under the Hazardous Products Act, while each province or territory's occupational health and safety regulator inspects employers.
WHMIS — the Workplace Hazardous Materials Information System — is Canada’s national system for communicating the hazards of chemicals used, stored, and handled in Canadian workplaces. It sets out what suppliers, employers, and workers each need to do to keep hazardous products identified, labelled, and understood. For employers, the obligations are specific, ongoing, and enforceable. This guide covers what they are in practice.
The three pillars every employer program rests on
WHMIS applies to any hazardous product used, stored, handled, or disposed of in a Canadian workplace, and it is built around three pillars: hazard classification, labelling, and Safety Data Sheets. Suppliers classify products, supply compliant labels, and provide an up-to-date SDS for each hazardous product they sell or import. Once those products enter your workplace, the responsibility shifts to you. Our overview of WHMIS responsibilities shows how the supplier, employer and worker roles fit together.
What are an employer’s obligations under WHMIS?
Employers who use hazardous products in the workplace must:
- Ensure all hazardous products are properly labelled
- Maintain an accessible, up-to-date SDS for every hazardous product on site
- Educate and train workers on the hazards of products they work with, and on how to read labels and SDS
- Establish workplace-specific procedures for safe handling, use, storage, and emergency response
- Review and update training and SDS on a regular basis
Each of these duties is continuous. A compliant SDS library in January can be non-compliant by June if suppliers issue updates that never reach your binder or database.
The five obligations at a glance
| Obligation | What it requires | How to show an inspector you meet it |
|---|---|---|
| Labelling | A supplier label on every hazardous product as received; a workplace label on decanted or made-on-site products | Labels intact and legible on every container; a workplace label procedure |
| SDS access | A current SDS for every hazardous product, readily available to workers on every shift | An SDS inventory that matches the products on site, with no outdated versions |
| Worker education and training | General WHMIS education plus training on the products and procedures of that workplace | Training records showing content covered, date and attendees |
| Safe-work procedures | Written procedures for handling, storage, exposure control and emergencies | Procedures that name the actual products and are known to the workers using them |
| Program review | Training and SDS reviewed regularly — at least annually in most jurisdictions, and when conditions change | Dated review records and SDS revision dates |
When does a product need a workplace label?
Supplier labels must stay on hazardous products as received — an employer may never remove, alter or deface one, and must replace it with a workplace label if it is lost or becomes illegible. A workplace label is also required when a hazardous product is transferred into another container, and when a product is produced in the workplace and used there. It must show the product identifier, safe handling information, and a statement that an SDS is available. Placards and other signage can serve the same purpose for products that are not in containers, such as bulk storage or material in process.
Who needs WHMIS training?
Any worker who works with, handles, or may be exposed to a hazardous product in a Canadian workplace is required to receive WHMIS training. The scope is intentionally broad: “may be exposed” captures workers who are present where hazardous products are used, stored, or transported, even if they never personally handle them. That commonly includes maintenance staff, cleaners, administrative employees whose offices share a building with a laboratory or workshop, and supervisors who oversee work involving hazardous products.
In practice this reaches virtually every sector. In schools and universities it covers custodial and maintenance staff, science teachers and lab technicians, trades instructors, and facilities personnel — and students in programs such as chemistry labs, welding, or cosmetology typically require training before they begin. In healthcare, nurses, physicians, lab technicians, housekeeping, and facilities workers all work with or near cleaning and disinfecting agents, laboratory chemicals, pharmaceutical compounds, and sterilization materials. In municipalities, public works employees, transit maintenance workers, parks staff, water treatment operators, and building maintenance crews all regularly encounter hazardous products.
Temporary workers, contractors, and new employees all require WHMIS training before they begin working with hazardous products — and it is the employer on whose premises the work happens, not the staffing agency, who is responsible for ensuring everyone has received appropriate site-specific education.
Is an online WHMIS course enough?
A generic online WHMIS course is not enough on its own. Employers are required to supplement general WHMIS education with training specific to the hazardous products actually present in that workplace, the procedures used to control exposure, and the emergency response measures in place. A worker who completed a general online course but has not received site-specific instruction has not fully satisfied the employer’s legal obligation. Keep records that document the content covered, the date, and the attendees.
Who enforces WHMIS obligations?
WHMIS enforcement is divided between two levels of government. Health Canada enforces at the supplier level under the Hazardous Products Act and Hazardous Products Regulations, covering product classification, label content, and SDS compliance. Once a product enters a workplace, jurisdiction passes to the provincial or territorial occupational health and safety regulator — the Ministry of Labour under the OHSA in Ontario, WorkSafeBC in British Columbia, OHS officers under the OHS Act in Alberta, CNESST in Quebec, and equivalent bodies everywhere else. Federally regulated workplaces — banks, telecommunications, interprovincial transportation — fall under the Labour Program at Employment and Social Development Canada under the Canada Labour Code.
The result: a Canadian employer is accountable to two separate regulatory authorities — Health Canada for the products they purchase and their SDS, and their provincial OHS regulator for how they manage those products and train their workers. Our guide to SDS compliance requirements by province lists the regulator and legislation for every jurisdiction.
Keeping your SDS library current
How often an SDS must be updated depends on your jurisdiction. Some provinces require an updated SDS within 90 days of significant new hazard information; others require employers to actively seek updated SDS every three years. Either way, when significant new data is released — such as the amendments covered in our WHMIS 2025 compliance update — every employer in every jurisdiction must obtain updated SDS reflecting those changes. Building supplier contact and SDS verification into an annual cycle remains the best practice regardless of where you operate.
An SDS kept electronically counts as accessible only when workers are trained to reach it, the device is available and working on every shift, and a paper copy is provided on request. CanadaSDS WHMIS compliance software keeps every location’s SDS library current in English and French, with 24/7 access online, on mobile or by QR code.
Frequently asked questions
A Canadian employer must ensure every hazardous product in the workplace is properly labelled, keep an up-to-date Safety Data Sheet (SDS) readily accessible to workers for each hazardous product, educate and train workers on the hazards and safe use of those products, establish workplace-specific procedures for safe handling, storage and emergencies, and review the training program and SDS regularly — at least once a year in most jurisdictions, and whenever conditions or hazard information change.
Any worker who works with, handles or may be exposed to a hazardous product in a Canadian workplace. That includes workers who never handle products themselves but are present where they are used or stored — custodial and maintenance staff, administrative employees sharing a building with a lab or workshop, and supervisors — as well as new employees, temporary workers and contractors, who must be trained before they begin.
No. A generic online course can cover general WHMIS education, but employers must add workplace-specific training on the hazardous products actually present, the procedures used to control exposure, and the emergency measures in place. A worker who has only completed a general course has not received all the training the employer is legally required to provide.
A workplace label is required when a hazardous product is transferred from its original container into another one, when a product is produced in the workplace and used there, and when a supplier label is lost or becomes illegible. A workplace label shows the product identifier, safe handling information and a statement that an SDS is available. Employers must never remove, alter or deface a supplier label.
Yes, provided workers are trained to access them, the computer or device is readily available and kept in working order throughout every shift, and a paper copy is provided on request. Whatever the format, the SDS for each hazardous product must be current and accessible to workers and to the joint health and safety committee or representative at all times.
The province or territory's occupational health and safety regulator enforces employer duties — for example, the Ministry of Labour, Immigration, Training and Skills Development in Ontario, WorkSafeBC in British Columbia and CNESST in Quebec. Federally regulated workplaces such as banks, telecommunications and interprovincial transportation fall under the Labour Program at Employment and Social Development Canada. Health Canada enforces supplier obligations under the Hazardous Products Act.
