The Employer and the Workplace Hazardous Materials Information System (WHMIS)

What is WHMIS?

The Workplace Hazardous Materials Information System, or WHMIS as it is often called, is a national system designed to ensure that all employers obtain the information that they need to inform and train their employees properly about hazardous materials used in the workplace. Through legislation, the WHMIS consensus establishes uniform requirements to ensure that the hazards of materials produced or sold in, imported into, or used within workplaces in Canada are identified by suppliers and employers using standard classification criteria.

WHMIS is consistent with the worker's "right to know" what the hazards are and what needs to be done to control them in the workplace. Existing occupational health and safety legislation in Canada requires that workers be informed about the risks they may encounter on the job. WHMIS provides employers and workers with one additional tool to improve their understanding of hazardous materials. To make the best use of this tool, suppliers and employers have certain responsibilities.

A "supplier" is a manufacturer, processor or packager of a controlled product or a person who, in the course of business, imports or sells controlled products. A "controlled" product is defined for WHMIS under the federal Hazardous Products Act as meaning any product, material or substance specified by the regulations to be included in any of the classes listed in Schedule II of the Act. An "employer" is, for the purposes of WHMIS, the user of a controlled product in the workplace or the producer of a controlled product as part of a workplace process.

Suppliers must convey hazard information to purchasers in a specified manner by means of labelling on the controlled products or containers of the controlled products and by providing more detailed information concerning the controlled product in the form of a material safety data sheet (MSDS).

Under occupational health and safety legislation, employers are also required to provide their employees with hazard information received from suppliers and in respect of controlled products produced in the workplace.

Employers' Responsibilities

Use of Labels and Other Forms of Warning in the Workplace

Employers must ensure that supplier-provided containers of controlled products are labelled with WHMIS supplier labels. As long as a controlled product remains in its supplier- provided container, the supplier label must remain attached to the container and legible.

For workplace processes, employers are required to furnish some form of workplace warnings such as labels, tags or markings. Although there is no specified format for workplace labelling and other forms of hazard warnings, information on the safe handling, storage and use of the controlled product and a product identifier (e.g., brand name, code name or the chemical name of the product) must be provided. Reference must also be made to the availability of a material safety data sheet.

Where a controlled product at the workplace is contained in a pipe, a piping system including valves, a process or reaction vessel, a tank car or tank truck, ore car, conveyor belt or similar conveyance, the employer must ensure that the content is clearly identified to workers through appropriate means and through worker education. Other provisions have been made for portable containers and decanted products under various circumstances, as well as for labelling procedures in laboratories.

For controlled products or containers of controlled products received in bulk or multi-container shipments, employers are required to provide the supplier information on a supplier or workplace label or by any other appropriate form of hazard warning.

Use of Material Safety Data Sheets (MSDSs)

Employers are responsible for obtaining from suppliers an MSDS for each controlled product used in their workplaces. The employer may also develop an MSDS to use at the workplace instead of a supplier MSDS, provided that the employer MSDS contains at least the same information found on the supplier MSDS and indicates that a supplier MSDS is available. MSDSs are to be updated at least every three years or as soon as further information relating to the hazard becomes available for a material.

The format in which the MSDS information is provided is not specified. However, while the information can be computerized or stored by the most practicable and cost- effective means, there are minimum content requirements for MSDSs. Employers should become aware of what the MSDS requirements are for a controlled product produced in a workplace process by referring to the Controlled Products Regulations of the federal Hazardous Products Act.

As an important source of detailed information on controlled products, supplier and employer MSDSs for controlled products are to be readily accessible to employees at each work site and supplied or made accessible to safety and health committees or representatives.

Employee Education and Training

Besides disclosing to workers hazard information on controlled products, employers are to ensure that instruction is provided for employees who handle, are exposed to, or are likely to handle or be exposed to hazardous materials. This should result in the employees becoming more aware of and better able to apply hazard information to ensure their health and safety.

The instruction should include a description of all the mandatory and performance-oriented aspects of WHMIS and of the responsibilities of the employer and employees. The employee education program should include:

  • instructions with respect to the product identifier;
  • instruction on the content required on the supplier and workplace label and the purpose and significance of the information contained on the label;
  • instruction on the content required on an MSDS and the purpose and significance of the information contained on an MSDS;
  • procedures for the safe handling, use, storage and disposal of a controlled product, including information relating to the disposal of a controlled product contained or transported in piping systems and vessels; and
  • procedures to be followed in the case of an emergency involving a controlled product.

Employers are required to consult with health and safety committees or representatives, where they exist, during the development of education and training activities with respect to exposure to hazardous materials. Employers are required to review the information and training provided to workers concerning hazardous materials in consultation with the health and safety committees or representatives at least annually, or more frequently if new hazard information becomes available or if required by a change of conditions.

Hazard Identification and Ingredient Disclosure

Employers are responsible for evaluating those products produced in a workplace process using the hazard criteria identified in the Controlled Products Regulations.

Subject to a confidential business information exemption and specific concentration cut-off limits, all ingredients of a controlled product that fall into any of the following categories must be disclosed on an employer-developed MSDS:

  1. an ingredient identified as being hazardous under the WHMIS criteria,
  2. an ingredient included on the Ingredient Disclosure List established by the Hazardous Products Act
  3. an ingredient that the employer has reasonable grounds to believe may be harmful, or
  4. an ingredient whose toxicological properties are not known.

Confidential Business Information Exemptions

WHMIS strikes a balance between the employee's need for protection and the employer's need to protect the confidentiality of business information.

An employer may consider claiming for some product information that is eligible for exemption, namely:

  • the chemical identity of any ingredient of a controlled product;
  • the concentration of any ingredient of a controlled product;
  • the name of any toxicological study that identifies any ingredient of a controlled product;
  • the chemical name, common name, generic name, trade name or brand name of a controlled product; and
  • information that could be used to identify a supplier of a controlled product.

All requests by employers for the non-disclosure of information on an MSDS or label for controlled products must be submitted to the Hazardous Materials Information Review Commission for review and validation. Where information is withheld by means of a confidential business information claim, a notation is to be made by the employer on the MSDS or label to that effect, together with the registration number assigned to the claim.

For details about the confidential business information claims, you may contact the:

Hazardous Materials Information Review Commission
200 Kent Street, Suite 9000, Ottawa, Ontario K1A 0C9
Telephone: 613-993-4331
Facsimile: 613-993-4686
Online: Hazardous Materials Information Review Commission Website

Provision of Confidential Business Information in the Case of Emergencies

An employer must immediately disclose in confidence to a physician or registered or licensed nurse confidential business information in his or her possession about a controlled product when the information is needed for the medical diagnosis of, or for rendering medical treatment to, employees in an emergency.

Additional Information on WHMIS

For further information about employer responsibilities under the legislation, contact the Federal Labour Program office nearest you.

Copies of the Hazardous Products Act and Controlled Products Regulations can be obtained by writing to:

Canada Government Publishing
Ottawa, Ontario K1A 0S9
Telephone Orders: 819-956-4802
Online: publications.gc.ca

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