Workplace impairment questions and answers

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General questions

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.

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.

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 cannabis for medical purposes 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

What are employers’ responsibilities with regard to workplace impairment?

Currently, there is no specific provision in the Canada Labour Code (Code) addressing the use of drugs and alcohol in the workplace. However, the Code does require that employers develop and implement Hazard Prevention Programs to protect employees from workplace hazards, which may include policies related to impairment including the use of drugs and alcohol.

In addition, the Cannabis Act includes amendments to the Non-Smokers’ Health Act (NSHA) to prohibit the smoking and vaping of cannabis in workplaces. The purpose of the NSHA is to protect non-smokers from second-hand smoke in federally regulated workplaces and on certain modes of transportation. Once the changes in the Cannabis Act come into force, there will also be obligations on employers and employees through the NSHA.

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

The Canadian Centre for Occupational Health and Safety's has a number of helpful resources, including its Guide to Writing an OHS Policy Statement and its white paper entitled “Workplace strategies: Risk of impairment from Cannabis ”.

What are the rules for drug testing in Canada?

Testing for alcohol and drug use in federally regulated workplaces is currently guided by a body of decisions from labour arbitrators, human rights tribunals and courts.  At the heart of this jurisprudence is an effort to balance two competing objectives: preserving individuals’ human and privacy rights; and ensuring safety for employees and the public.

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 specific situations. The Canadian Human Rights Commission has published a document entitled Impaired at work: A guide to accommodating substance dependence, which includes key considerations for drug and alcohol testing, and accommodations in the context of the Canadian Human Rights Act.

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.

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.

What happens if there is an after work event and alcohol or cannabis is taken?

The role of the Labour Program is to legislate and regulate health and safety issues in the workplace. Outside of this, employers have the right to implement policies concerning substances as they see fit. This right extends to the use of substances such as cannabis and alcohol in the workplace.

If you are an employee

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.

The Canada Labour Code doesn’t speak to impairment directly, but speaks to hazards to health and safety and that workplace parties are to work together to develop a clear policy that is adapted and reflects their reality and that address all potential hazards in their workplace, including hazards posed by impairment.

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.

Employees may also wish to address the issue by following the Internal Complaint resolution process under Part II of the Code. Under this process, the employee’s supervisor must first attempt to resolve the matter with the employee. If it can’t be resolved at that level, the complaint is then referred to the Workplace Health & Safety Committee (or the Health & Safety Representative and a designated management member) to investigate the complaint and provide recommendations to the employer. If the matter remains unresolved after this stage, the complaint can then be submitted to the Labour Program for one of our Health & Safety officers to investigate.

However, if the employees perceive the situation to be a danger, they can instead exercise their right to refuse work under section 128 of the Code, Part II.

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