Canadian contractors fear the impending legalization of marijuana next year could undermine efforts to cut down on workplace accidents and enforce site safety rules. 

The federal government is pushing ahead with plans to legalize recreational marijuana, with new rules set to take effect by July 1.

The Ontario General Contractors Association has taken the lead in raising the alarm about legalized cannabis, arguing that government regulators are not looking closely enough at workplace safety impacts, especially in the construction industry.

"We already have workers showing up under the influence and using it during breaks," said David Frame, government affairs director for the Ontario General Contractors Association. "We have had some notable accidents in our industry due to impairment. We anticipate great use with legalization."

Frame pointed to a 2009 Toronto high-rise construction accident in which four workers plunged to their deaths after their overloaded scaffold collapsed. Three of the workers had marijuana in their systems at the time, according to published reports.

The Ontario contractors group, as well its counterparts in the province of Saskatchewan and the city of Winnipeg, want provincial governments, which will be in charge of determining the rules around legalization, to beef up regulations related to construction-work safety.

"Most employers have a zero-tolerance drug policy, marijuana being an illegal substance," said Mark Cooper, president of the Saskatchewan Construction Association. "Once it becomes legalized, it will become a lot more complicated. At the end of the day, we need to protect the lives and limbs of others who may be on the site."

Workplace Safety Gaps

Government officials on the provincial and federal level appear to be focusing more on rules related to the distribution and sale of pot than on its impact on workplace safety, Frame said.

Gloria Yip, a spokeswoman for Ontario’s Ministry of Labor, said the province’s new rules will bar recreational pot from being used outside private residences. Further, the province is "developing resources to guide employers, labor groups and others as they manage workplace safety issues, related to impairment at work, through education and awareness initiatives, which will be available in advance of legalization," she said.

But Frame said contractors have many unanswered questions related to the new federal rules, particularly as they relate to the ability to do random drug testing. Current testing is limited to pre-job and post-incident and, for the most part, focuses on determining whether someone has used cannabis, not the extent of impairment.

Cooper further observes that there is no reliable way to test for impairment as it relates to marijuana, other than by taking a sample of someone’s blood.

"We would like to see exceptions in both federal and provincial rules that randomized testing would be allowed," Cooper said. "Companies can do it, but they can be challenged" in court.

Testing Uncertainties

As it stands now, though, Canadian courts have only allowed random testing if there is a well-documented drug problem that is causing serious accidents, notes Norm Keith, a senior partner at Fasken Martineau and an occupational health and safety defense lawyer.

A contractor that starts randomly testing employees for drug use, especially if it’s a union shop, could easily wind up in court, said Keith, author of “Alcohol & Drugs in the Canadian Workplace — An Employer’s Guide.”

Says Keith: “The Supreme Court of Canada, both literally and figuratively in its ivory tower in Ottawa, says you need more injuries and death to do random testing."

Even as employers are restricted in the type of testing they do, they are on the hook should an employee high on marijuana suffer an injury or trigger a workplace accident that hurts others, said George Waggott, a labor lawyer in the Toronto office of McMillan.

“We have had situations where the liability attaches to the supervisor,” Waggott said. “The safety issue is a huge problem for the employer.”

Beyond the issue of testing, contractors will have to hammer out policies to deal with marijuana use. Simple evidence that someone has used pot no longer carries the same legal consequences, especially with the rise of medical marijuana, which has been legal in Canada for some time.

In order to prevent workers who are stoned or otherwise impaired by pot from endangering colleagues, contractors need a comprehensive “fit for duty” policy, both Waggott and Keith noted.

Simply smelling pot on someone is not enough to determine impairment, because the worker in question could simply have been around someone else smoking marijuana, similar to the scent of secondhand cigarette smoke, Waggott said.

One way is to set up a series of tests, similar to those used to determine disability in workers comp cases, to detect impairment from pot, Waggott said. That could involve requiring the worker to go through the tasks for the job; they might also have to be asked to follow instructions or a conversation.

Even that approach is far from foolproof, the legal experts said.

“The problem is that it gets you part of the way there but mental acuity is much harder to determine,” Waggott said.