Workplace impairment questions and answers

1. What is workplace impairment?

Impairment commonly refers to an altered state of physical and/or mental functioning. In a workplace context, someone who is impaired may have difficulty completing tasks in a safe manner and may put themselves, their coworkers and the public in danger.

For more information on impairment in the workplace, visit the Canadian Centre for Occupational Health and Safety webpage on impairment at work.

2. What are potential causes of workplace impairment?

There are many potential causes of workplace impairment, including the use of legal and illegal substances such as alcohol, cannabis, street drugs and certain medications, as well as factors such as fatigue and certain medical conditions.

For more information on impairment in the workplace, visit the Canadian Centre for Occupational Health and Safety webpage on impairment at work.

3. What about the use of cannabis for medical purposes in the workplace?

The use of cannabis for medical purposes must be treated like any other prescription medication. An employee who has all of the necessary legal and medical authorizations to possess and use medical marijuana triggers an employer’s obligation to accommodate its use to the point of undue hardship.

For more information on impairment in the workplace, visit the Canadian Centre for Occupational Health and Safety webpage on medical marijuana.

If you are an employer

1. What are employers’ responsibilities with regard to workplace impairment?

Employers are responsible for developing, implementing and monitoring Hazard Prevention Programs, which should include policies around any potential hazard in the workplace, such as the use of drugs, alcohol, or other substances.

The Cannabis Act includes amendments to the Non-smokers’ Health Act to prohibit the smoking and vaping of cannabis in workplaces. Once the changes in the Cannabis Act come into force, there will also be obligations on employers and employees through the Non-smokers’ Health Act.

Currently, there is no specific provision in the Canada Labour Code addressing the use of drugs and alcohol in the workplace. However the Code does require that employers put in place measures to protect employees from workplace hazards, which may include policies related to impairment including the use of drugs and alcohol.

2. Why should you have an occupational health and safety (OHS) policy statement? And how could you write it?

For any questions about writing an occupational health and safety policy statement, visit the Canadian Centre for Occupational Health and Safety's Guide to Writing an OHS Policy Statement.

3. What are the rules for drug testing in Canada?

Testing for alcohol and drug use in federally regulated workplaces is currently governed by a body of decisions from labour arbitrators, human rights tribunals and courts. The Canadian Human Rights Commission has published a document entitled Impaired at Work: A guide to accommodating substance dependence (pdf version, 1,166.96KB), which includes key considerations for drug and alcohol testing in the context of the Canadian Human Rights Act.

While decisions are case-by-case and the case law is evolving, under existing jurisprudence, an employer testing employees for drug and/or alcohol use in “safety-sensitive” positions (defined as those in which incapacity due to impairment could result in direct and significant risk of injury to the employee, others or the environment) is generally permissible in the following situations:

  • for “reasonable cause,” namely where an employee reports for work in an unfit state and there is evidence of substance use;
  • after a significant incident or accident where there is evidence that an employee’s action or omission may have contributed to the incident or accident; and
  • as part of a return to work agreement, following treatment for alcohol or drug use, or disclosure of a current alcohol or drug dependency or problematic use.

Random testing of employees in safety-sensitive positions may be permissible in the following limited circumstances: where the employer is able to show that there is a demonstrated alcohol or drug abuse problem amongst employees in safety-sensitive positions in the workplace and testing is a proportionate response (in other words when potential safety benefits outweigh potential intrusion into employee privacy) and when the employer still meets its duty to accommodate employees who test positive.

Drug or alcohol testing of an employee who does not occupy a safety-sensitive position is rarely permissible.

For more information on how to accommodate substance dependence, please read the Canadian Human Rights Commission’s guide Impaired at Work – A guide to accommodating substance dependence.

4. Are there alternatives to drug testing?

The Canadian Human Rights Commission (CHRC) recommends that employers, wherever possible, rely on observation, supervision and frequent face-to-face conversations as a way to recognize when an employee is impaired. However, the CHRC states that for safety-sensitive jobs, employers must always use a safety-first approach.

If you are an employee

1. What are employees’ responsibilities with regard to workplace impairment?

Employees have a duty to work safely and to understand that using substances (medical/therapeutic or non-medical) may pose serious health and safety risks to themselves, their co-workers and the public.

The Cannabis Act includes amendments to the Non-smokers’ Health Act to prohibit the smoking and vaping of cannabis in workplaces. Once the changes in the Cannabis Act come into force, there will also be obligations on employers and employees through the Non-smokers’ Health Act.

Currently, there is no specific provision in the Canada Labour Code addressing the use of drugs and alcohol in the workplace. However the Code does require that employers put in place measures to protect employees from workplace hazards, which may include policies related to impairment including the use of drugs and alcohol.

2. What if I become aware of substance use in the workplace?

Employees should report to their employer any object or circumstance in the workplace that is likely to be hazardous to their health or safety, or that of others.

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