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Part of Cannabis and your health

The Conference Board of Canada and The Globe and Mail are partnering to explore the relationship between career success and cannabis use. Employers and employees (both recreational and medical cannabis users, as well as non-cannabis users) are invited to participate in this study. (Employees interested in taking the survey can click on this link. Employers interested in taking the survey can click on this link.) The data from these surveys will be aggregated and used to conduct analysis and create a report that will be presented Oct. 15, 2019, at a conference at The Globe and Mail Centre in Toronto.

Bill Howatt is the head of research, workforce and productivity at the Conference Board of Canada. Lorenzo Lisi is the leader of the workplace law group at Aird & Berlis LLP.

As the one-year anniversary of legal recreational cannabis in Canada draws near, many employers have found that their existing substance-use policies effectively address its use. But with the upcoming legalization of edibles, there is renewed concern about how to manage the risks of impairment at work.


Health Canada recently set out rules governing the legal production and sale of edible, extract, and topical forms of cannabis. Such products will become legal to sell on Oct. 17, 2019, and are expected to hit the market in late December or early next year.

Demand for edibles is expected to be high, and their sale may lead to more recreational users. The cannabis shortage that occurred early in the first year of legalization means the number of users will likely continue to rise as licensed production increases.

The risk of cannabis-related medical emergencies may also increase, due to a lack of knowledge about edibles. The human body processes cannabis more slowly when it is eaten than when it is smoked, so it takes longer for the high to kick in – sometimes 60 minutes or more. Inexperienced users may become impatient and eat more, putting themselves at risk for a medical episode. The time a person spends impaired is also usually longer after consuming edibles than after smoking or vaping cannabis.

The law continues to evolve when it comes to issues of accommodation and impairment. Recently, in the case of IBEW, Local 1620 v. Lower Churchill Transmission Construction Employers’ Association Inc., the Supreme Court of Newfoundland recently dealt with an appeal from an arbitrator’s decision that upheld the employer’s ability to deny employment on a construction project due to the employee’s use of medically prescribed cannabis that was used to treat pain caused by two separate medical conditions.

The employer took the position that the employee’s use created a risk of impairment on the job site, even though there was no accepted measure of impairment based on current technology. The employer asserted that their inability to measure and manage the risk of harm constituted undue hardship. The employee’s union felt the decision stigmatized and stereotyped cannabis users.

The court determined that the arbitrator’s decision was reasonable and, more importantly, it set out a framework to assess impairment and accommodation where cannabis is involved. This case found that cannabis use can impair a worker’s ability to function safely for up to 24 hours after use, that its effects might not be apparent to the user, and that there is currently no accurate test for cannabis impairment.

The court’s willingness to find that undue hardship can exist even in the absence of accepted testing methods for impairment is particularly encouraging for employers struggling to ensure the safety of both employees and customers in the aftermath of cannabis legalization.


Employers are particularly worried about consumption of cannabis edibles because it is undetectable through smell. This means they need to become more observant with respect to possible impairment in the workplace.

But better ways to detect impairment won’t change the way some employers approach cannabis. Many say they’ve been addressing this issue for years and have simply switched their focus from treating cannabis as illegal to preventing employees from working while under the influence of any substance. Diligent employers who are flexible and practical when dealing with employee cannabis use will be better able to deal with the associated risks.

Employers should also consider educating employees on how cannabis works in the body, especially edibles, and on the risks of impairment in the workplace. But this doesn’t mean they should resort to random searches, testing (except possibly in safety-sensitive positions) or zero tolerance of recreational use.


Preparation is the best way to manage cannabis risk in the workplace. Here are four steps employers can follow:

  1. Evaluate your current substance-use policies and fit-for-duty expectations. Audit employees’ knowledge about cannabis and your policies to determine the risk of non-conformity.
  2. Reinforce how important it is for all employees to be familiar with substance-use policies and fit-for-duty expectations. Clearly communicate any new policies or changes and make sure employees understand their rights and responsibilities.
  3. Educate all employees using available online training about the functions of cannabis, the link between stress, cannabis and addiction risk and the accommodations process for medical cannabis users.
  4. Train managers on how to talk to employees who may be at risk for impairment or substance-abuse issues in the workplace.

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