Shop Talk: Cannabis

Shop Talk: Cannabis

​​​What will we do today to prevent an incident?

Cannabis, also known as marijuana, weed, pot and grass, is a drug that is used recreationally and in some cases as a medical Two workers read a Drug and Alcohol Policy treatment. 

What’s the hazard? 

Using cannabis can make you impaired. The effects of cannabis can include:  drowsiness, impairment of motor skills, impaired memory, disturbances in ability to concentrate, and disturbances in ability to think and make decisions. 

The effects of cannabis vary from person to person. The amount of THC (the chemical that causes the high) and how the cannabis is consumed (e.g., inhaled, eaten, etc.) are just two of many factors that can affect how a person reacts to cannabis. Cannabis impairment can impact your safety and the safety of others at your workplace. 

What can happen? 

John works as a roofer. Prior to coming to work one day, John smoked some marijuana. When he got to work, he climbed onto the roof of a two-storey house to nail shingles, but he forgot to clip his fall arrest harness onto the safety line. As he was nailing his last shingle, he miss-stepped and fell off the roof. John suffered a severe head injury upon hitting the ground. 

Based on the scenario above, here are some questions that could be used to spark discussion: 

  1. Did John have the ability to perform the above job safely? 
  2. How could this injury have been prevented? 
  3. What should you do if you suspect someone is impaired at work? 

What can be done to prevent cannabis impairment in the workplace? 

All workplaces should have a drug and alcohol policy that addresses the potential for cannabis impairment in the workplace. Best practices for employers include the following
  • creating and enforcing a drug and alcohol policy, and ensuring all staff understand it 

  • clearly indicating their position on cannabis use in the workplace 

  • training supervisors and workers on identifying and responding to potential impairment due to cannabis 

  • accommodating workers who have an addiction or who are medically authorized to use cannabis for a disabling medical condition, with input from the workers’ physicians or other medical professionals – accommodation must be attempted up to the point of undue hardship on the employer 

  • making it clear that there will be no threat of judgment or reprisal if a worker discloses that they are using medical cannabis or have an addiction 

  • providing cannabis impairment prevention strategies and supports (e.g., an Employee Assistance Program) 

  • providing the proper procedures for reporting cannabis impairment in the workplace 

  • providing the procedures that will be followed if a worker is found to be impaired by cannabis at work. 

Caution: If the employer suspects impairment, it is appropriate to ask the worker what is going on. However, this does not give the employer the right to ask for or access the worker’s personal health information.

Part 2.19(2) of The Workplace Safety and Health Regulation states: A worker must not work while under the influence of alcohol or a drug that impairs or could impair the worker’s ability to perform work safely. 

All workers should also: 
  • understand and follow their workplace’s drug and alcohol policy 
  • take responsibility to ensure their own safety and the safety of others 
  • encourage their co-workers to seek help if they believe there is a potential breach of the drug and alcohol policy. 
The information contained in this resource is not legal advice and should not be relied on as such. 

Other resources: 

Some additional SAFE Work Manitoba resources include: 
*Please note that employers should seek legal counsel when developing their own drug and alcohol policies, as each policy should be unique to each workplace. Do not copy a policy.

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For more information: 204-957-SAFE (7233) or toll-free 1-855-957-SAFE (7233).


The following external resources were consulted in the development of this document, and were valid at the date of publication. 

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