WHMIS stands for the Workplace Hazardous Materials Information System. It is a national hazardous materials classification system designed to provide workplace standards for the control, handling, storage, and disposal of ‘controlled’ products.

Controlled products are hazardous materials that can impact the health and safety of the workplace and its employees.

WHMIS consists of three main parts: labels, material safety data sheets (MSDSs), and worker education and training.

A WHMIS program is required in all workplaces that may have controlled products. Employers must provide workers with information regarding safety and health hazards in their workplaces. Employees have the right to know of potential dangers that can affect their work and health.

WHMIS standards are coordinated between three levels of government: federal, provincial, and territorial. Supplier labeling and MSDS requirements fall under the federal Hazardous Products Act.

Each province and territory establishes WHMIS employer requirements within its own jurisdiction. In Ontario, these requirements are set out in the WHMIS Regulation 860, which falls under the Occupational Health and Safety Act. The Ministry of Labour (MOL) provides provincial enforcement of the WHMIS Regulation.

Labels – Supplier and workplace labels are required by WHMIS legislation.  Supplier labels must be in both English and French and are created by the supplier and should be affixed to the product container before shipping to a company.  Seven items must be present on a supplier label:

  • Product name
  • Supplier name
  • Statement of MSDS (proof of an MSDS sheet with more information)
  • Appropriate hazard symbol
  • Risk phrases (warnings about potential health risks)
  • Precautionary measures
  • First aid measures

Workplace labels are used when the product is being transferred from its original supplier container to a different one.  It is also used when the supplier label is illegible, accidentally removed or if the product is produced in the workplace.  Workplace labels must contain the following information:

  • Identity of product
  • Safe handling procedures
  • Statement that an MSDS is available

Material Safety Data Sheets (MSDSs) – These contain correct handling information for the product.  It is broken into nine categories with the following information:

  • Product information
  • Hazardous ingredients (name, concentration and toxicity of each ingredient)
  • Physical data (i.e. powder vs liquid)
  • Fire / explosion hazard (conditions where the product can catch fire)
  • Reactivity data (how reactive is product to other chemicals)
  • Toxicological properties (how the product can enter the body; short and long-term health effects)
  • Preventive measures (precautions, handling, emergency procedures)
  • First aid measures
  • Preparation information (name, phone number of person/group who created the MSDS and the date it was created)

Worker Education Program – The employer must provide information and instruction to all workers who work with, or near a controlled product. This means that the employer must provide training to anyone who stores, handles, uses of disposes of the product; anyone who immediately supervises another worker who performs the above duties; and anyone whose health and safety could be at risk during storage, handling, uses or disposes a controlled product; during maintenance activities; or during emergencies such as spills.

The employer must also consult with the joint health and safety committee or health and safety representative in the development, implementation and review of the WHMIS worker education program.

The worker education program must be reviewed at least once a year, or more often if new information on a controlled product becomes available, or if workplace conditions change. The review is intended to identify whether worker retraining and updating of the education program are necessary.

WHMIS Classes

Class A – Compressed Gas
Contents inside the container are under pressure.  If the container is damaged, there is a risk of explosion or the produce may act as a rocket if dropped.
Class A
Class B – Flammable and Combustible Material
Products can ignite, explode or react with other chemicals.  There are six divisions under Class B:
  • Division 1 – Flammable Gas
  • Division 2 – Flammable Liquid
  • Division 3 – Combustible Liquid
  • Division 4 – Flammable Solid
  • Division 5 – Flammable Aerosol
  • Division 6 – Reactive Flammable Material
Class B
Class C – Oxidizing Material
If this product comes into contact with oxygen or other organic material, it will ignite or explode.
Class C
Class D – Poisonous and Infectious Material 
There are three divisions under Class D: 
  • Division 1 – Materials causing immediate and serious toxic effects
    A worker can be poisoned or killed if this product enters the body.
  • Division 2 – Materials causing other toxic effects
    Workers may experience chronic health effects from exposure to the material.
    • Subdivision A – Very toxic material
    • Subdivision B – Toxic material
  • Division 3 – Biohazardous infectious material
    A worker may become infected with a disease if contact is made with this product.
Class D
Class D
Class D
Class E – Corrosive Material
Skin can burn or the worker may experience severe eye and skin irritations.
Class E
Class F – Dangerously Reactive Material
Highly unstable material that can react to other products, heat, light, or sudden movements.
Class F

How We Can Help

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Our health and safety conferences throughout Ontario provide excellent opportunities for networking and learning on lifting devices and other key topics. Visit Partners in Prevention 2010 Ontario Health & Safety Conference & Trade Show and the Conferences & Trade Shows section for more information.

Partner Sites

Farm Safety Association (FSA) - FSA provides health & safety information, resources and assistance to firms within the agricultural, horticultural and landscaping industries. Click the link to access their website for more information.

Ontario Service Safety Alliance (OSSA) - OSSA provides health & safety information, resources and assistance to firms within the service sector. Click the link to access their website for more information.

IAPA Resources