OSH Answers Fact Sheets

Easy-to-read, question-and-answer fact sheets covering a wide range of workplace health and safety topics, from hazards to diseases to ergonomics to workplace promotion. MORE ABOUT >

Download the free OSH Answers app
Download on the App Store Get it on Google Play

Search all fact sheets:

Type a word, a phrase, or ask a question

Impairment at Work

What is impairment at work?

We often think of impairment as a result of substance use or in terms of addiction or dependence to alcohol or drugs (used legally or illegally). While not formally defined by the Canadian Human Rights Commission describes the appearance of impairment at work as: “e.g. odor [sic] of alcohol or drugs, glassy or red eyes, unsteady gait, slurring, poor coordination.”

However, impairment can be the result of various situations, including many that are temporary or short term. Issues that may distract a person from focusing on their tasks include those that are related to family or relationship problems, fatigue (mental or physical), traumatic shock, or medical conditions or treatments. Examples include:

  • experiencing the effects of substance use, including alcohol or other drugs (legal or illegal)
  • treating illness or using medication(s) with side effects (such as radiotherapy causing tiredness, or antibiotics causing nausea)
  • having fatigue
  • being tired due to long work periods, or working more than one job
  • experiencing the disruption to body circadian rhythm caused by shiftwork
  • having a crisis in the person’s family
  • assisting a child or a family member or having a young infant
  • preparing for an external activity such as an exam or wedding
  • experiencing shock or insecurity after a workplace incident, fire, or robbery
  • having unresolved conflict with the employer, or among employees
  • experiencing sexual harassment or bullying
  • being exposed to extreme cold (results in lower mental alertness, less dexterity in hands, etc.) or heat (results in increased irritability, loss of concentration, loss of ability to do skilled tasks or heavy work, etc.)

Adapted from: “Temporary Impairment”, Department of Labour, New Zealand (2003)

Note that other issues, such as problematic gambling or shopping, may also be a cause of distraction, inattention, or making inappropriate decisions while at work. As such, they may also be considered a form of impairment.

How should a workplace respond to impairment?

In general, employers should consider if there is a risk to the individual’s safety or the safety of others. For example:

  • Does the person have the ability to perform the job or task safely (e.g., driving, operating machinery, use of sharp objects)?
  • Is there an impact on cognitive ability or judgement?

Each individual should be assessed on a case-by-case basis.

Employers should collaborate with employees, health and safety committee/representative, and union, (if present) to design a policy which outlines what is an acceptable code of behaviour, and an acceptable level of safety performance. The main goal is that workplaces are encouraged to establish a policy and procedure so that safety is maintained, and where necessary, help can be provided in a professional and consistent manner. The policy may also need to state how discussions will take place, what options are available if the ability to work safely is a concern (e.g., assigned less safety-critical work, sent home, etc.), and actions that may be taken. If an employee may be sent home, it should be clear if this action is taken, under what circumstances is it appropriate and whether it is done via sick time or how pay will be affected, if relevant.

The policy maybe combined as an impairment policy (that also covers substance use issues), or created separately.

Supervisors should be educated and trained regarding how to recognize impairment. In most cases, when assessing an individual for impairment, it is suggested that a second trained person be present to help make sure that there is an unbiased assessment.

Note: it is not the role of the supervisor or employer to diagnose a possible substance use or dependency problem. Their role is to identify if an employee is impaired, and to take the appropriate steps as per the organization’s policy.

What should be done if impairment is suspected?

If a supervisor or co-worker becomes aware of an employee who is showing signs of impairment (regardless of cause), it is very important that action is taken. Examples of corrective actions include but are not limited to:

  • Call for first aid or emergency medical assistance, if necessary.
  • Speak to the employee in a private area to discuss their behaviour.
  • Ask another supervisor or designated person to be present as a witness.
  • State your concerns about safety for others and themselves to the employee and request that they explain what is going on. Do not assume substances are the cause.
  • Based on employee response, discuss options, where applicable and available.
  • Follow the steps outlined in your organization’s program. In some cases, it may be necessary to assign non-safety sensitive work, or to ask the employee to stop their work.
  • If applicable, notify senior management and/or union representative.
  • Be familiar with available resources and supports (e.g., Employee Assistance Programs, or agencies within the local community), and help employees seek treatment as necessary. Encourage access and use of support programs, and reassure the employee that the services are voluntary and confidential.
  • If necessary, call a taxi or have employee escorted home; do not allow them to drive if you suspect impairment.
  • If disciplinary action is required, follow your organization’s policies on progressive discipline

Every discussion should be accompanied by an incident report. The report should include the events preceding the incident, identification of the employee’s unsafe work practices, the matters discussed with the employee, that management and union representatives were notified, a list of all actions taken, and any recommendations made to the employee.

Recall it is not the employer or supervisor’s duty to diagnose an employee, or to know if they have a disability. Employers can observe changes in an employee’s attendance, performance, or behaviour. They can initiate a discussion about the issue(s) as related to work, and discuss possible solutions. The discussion between the employer and employee may need to occur more than once. Document all discussions. Provide support and practice empathy, not sympathy. Focus on solutions, but if disciplinary action is necessary, it is important to follow through.

What can impairment look like?

Because impairment may be the result of various circumstances, the employer should develop a clear statement of what is considered to be impaired behaviour within their workplace. The Canadian Human Rights Commission uses the following characteristics as they relate to changes in an employee’s attendance, performance or behaviour:

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

Sometimes there are immediate signs and symptoms present. Other times, it is a pattern of behaviour that may be a concern. The following table is from “A Toolkit to Address Problematic Substance Use that Impacts the Workplace” as published by the Atlantic Canada Council on Addiction (ACCA) which can be used to help determine impairment in general.

ACCA notes the following about using signs and symptoms:

  • They may be different from person to person.
  • When used alone or in combination, they do not necessarily mean that somebody has a substance use problem. However, they may be indicators that your employee is in trouble or in need of some help (regardless of if the issue stems from problematic substance use or another cause).
Table 1
Signs and Symptoms of Problematic Substance Use
(not specific to any causal agent)
  • deterioration in appearance and/or personal hygiene
  • unexplained bruises
  • sweating
  • complaints of headaches
  • tremors
  • diarrhea and vomiting
  • abdominal/muscle cramps
  • restlessness
  • frequent use of breath mints/gum or mouthwash
  • odour of alcohol on breath
  • slurred speech
  • unsteady gait
Psychosocial impacts
  • family disharmony (e.g., how the colleagues speak of family members)
  • mood fluctuations (e.g., swinging from being extremely fatigued to ‘perkiness’ in a short period of time)
  • inappropriate verbal or emotional response
  • irritability
  • confusing or memory lapses
  • inappropriate responses/behaviours
  • isolation from colleagues
  • lack of focus/concentration and forgetfulness
  • lying and/or providing implausible excuses for behaviour
Workplace performance and professional image
  • calling in sick frequently (may work overtime)
  • moving to a position where there is less visibility or supervision
  • arriving late for work, leaving early
  • extended breaks; sometimes without telling colleagues they are leaving
  • forgetfulness
  • errors in judgement
  • deterioration in performance
  • excessive number of incidents/mistakes
  • non-compliance with policies
  • doing enough work to just ‘get by’
  • sloppy, illegible or incorrect work (e.g., writing, reports, etc.)
  • changes in work quality

Document last updated on September 12, 2017

Add a badge to your website or intranet so your workers can quickly find answers to their health and safety questions.


Although every effort is made to ensure the accuracy, currency and completeness of the information, CCOHS does not guarantee, warrant, represent or undertake that the information provided is correct, accurate or current. CCOHS is not liable for any loss, claim, or demand arising directly or indirectly from any use or reliance upon the information.