Workers Compensation Board of Prince Edward Island

Impairment in the Workplace

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In an effort to support workplace safety, the following information provides an overview of the potential risks resulting from impairment.

Impairment in the Workplace

Impairment at any worksite can have severe consequences for not only the impaired worker, but also their co-workers, supervisors, and employer. Impairment is a hazard, and as with any workplace hazard, employers must identify, assess, and control it.

Impairment may result from the use of alcohol or legal/illegal drugs. However, it may also be the result of fatigue, a medical condition, and life stresses (personal or work-related).

Impairment at work affects a worker’s ability to concentrate, think clearly, make decisions, and can lead to confrontational and aggressive behaviours.

Signs of Impairment

The Canadian Human Rights Commission lists the following as possible signs of impairment in the workplace:

  • personality changes or erratic behaviour
    • increased interpersonal conflicts
    • overreactions to criticism
  • appearance of impairment at work
    • odour of alcohol or drugs
    • glassy or red eyes
    • unsteady gait
    • slurring
    • poor coordination
  • working in an unsafe manner, involvement in an accident
  • failing a drug or alcohol test
  • increased absenteeism, reduced productivity or quality of work.

Displaying signs of impairment, such as red eyes, an unsteady gait or slurring words, does not necessarily indicate substance use or substance abuse. Employers and supervisors should not make assumptions about causes of impairment, and should talk to workers they believe may be impaired to properly investigate the situation further.


Employers have a responsibility to ensure a safe workplace and addressing the potential for workplace hazards, such as impairment, is part of that responsibility. Section 12.(1)(a) of the Occupational Health & Safety Act states;

An employer shall ensure that every reasonable precaution is taken to protect the occupational health and safety of persons at or near the workplace.

In addition, workers also have a responsibility to ensure a safe workplace. Section 16.(1)(a) of the Occupational Health & Safety Act states;

A worker, while at work, shall take every reasonable precaution to protect the worker’s own occupational health and safety and that of other persons at or near the workplace.

Reduce the Risk

Workers and employers share responsibility for managing impairment in the workplace.

Workers have a responsibility to ensure that

  • their ability to work safety is not impaired by alcohol, drugs, or other causes;
  • they notify their supervisor if their ability to work safely is impaired as a result of prescribed medication of for any other reason;
  • they notify their supervisor if they see someone who appears to be impaired.

Employers can address impairment by putting appropriate controls in place to eliminate, or minimize, the risk of impairment in the workplace. Controls include

  • having an up-to-date drug and alcohol policy;
  • providing policy training to everyone in the workplace;
  • enforcing the policy in a fair, consistent manner throughout the workplace;
  • refuse to allow a worker to perform activities where impairment may endanger the impaired worker of anyone else;
  • refuse to allow a worker to remain at any workplace while the worker’s ability to work safely is impaired by alcohol, drugs, or other causes;
  • train supervisors on identifying and responding to potential impairment;
  • accommodate workers on medical treatments or experiencing addiction.

What should be done if an impaired worker is suspected?

If a worker is showing signs of impairment, it is very important that action is taken. The Canadian Centre for Occupational Health and Safety recommends the following actions

  • if the person is in crisis, call 911;
  • be empathetic and do not judge;
  • speak with the worker in a private area to discuss their observed behaviour. Ask another supervisor or a designated person to be present as a witness;
  • identify your concerns to the worker and seek an explanation for what is going on. Do not assume that you know the cause of impairment;
  • based on the worker’s response, discuss options, including accommodation if applicable;
  • if necessary, ensure the worker has a safe way to get home;
  • if disciplinary action is required, follow your policy;
  • document the incident following every discussion;
  • be aware that you don’t need to diagnose the problem. More than one discussion with the worker and information from the worker’s physician or other medical professional may be required.

For additional information

PEI Laws on Use of Cannabis
What is Duty to Accommodate?
A Guide to Accommodating Substance Dependence
PEI Human Rights Commission
CCOHS Cannabis White Paper
OEMAC Position Statement on the Implications of Cannabis Use