The impending legalization of recreational marijuana presents challenging and unchartered territory for many employers in Canada. The forthcoming Cannabis Act, AKA Bill C-45, raises a number of questions regarding workplace safety and impairment, particularly for jobs that have the potential to place employees in harm’s way.

Here’s what employers need to know ahead of the law changes.

Is marijuana legal in Canada right now?

Not for recreational use, even though it is legal for verified medicinal purposes. The government had initially aimed to have the Cannabis Act passed before July of this year, but a packed Senate timetable led to a postponement. A final vote on the act is to be held by June 7.

Assuming the bill is passed by the Senate on this date, it will be another two to three months before provincial and territorial governments are prepared for retail sales – pushing back legalization until August, or September.

How will legalization affect the workplace?

Marijuana is the most commonly encountered substance in workplace drug testing already and widespread use is expected to increase exponentially once the bill passes.

Employers have expressed concerns that this proliferation of pot smoking could present an array of problems. This is particularly pertinent for those who run high-risk businesses, such as those where workers operate heavy machinery.

“The THC in cannabis can impair your ability to drive safely and operate equipment. It can also increase the risk of falls and other accidents,” warns Health Canada. “Impairment can last for more than 24 hours after cannabis use, well after other effects may have faded. People who use cannabis regularly may have trouble with certain skills needed to drive safely for weeks after their last use.”

Should employers amend policies?

Yes. Most businesses strictly forbid their employees from showing up to work drunk as part of their policies. If marijuana is not part of your employment policies and procedures, they should be updated to reflect your stance on it.

Similar to alcohol, there are no “blanket rules” against employees showing up to work impaired, explains Simone Ostrowski, a workplace lawyer with Whitten and Lublin.

“An employer can put in their policy that it’s prohibited to show up impaired or to be consuming marijuana at work and it’s not hard to do that,” she said. “A policy can be pretty basic, especially if the employer already has existing drug and alcohol policies in place. Generally speaking, it’s not going to be a crime or against any employment standards for an employee to show up impaired, unless the employer has a policy in place.”

Should employers take a zero tolerance stance against marijuana?

No, as employers still have a duty to accommodate employees who use marijuana medicinally. However, a ban on workers smoking weed recreationally at work or showing up high to the workplace without having a medical reason is recommended. You should look to clearly discern between the two when establishing policies on the matter.

“It’s more legally risky to establish a zero tolerance policy because of the duty to accommodate that all employers have. Employers should look at the case of each individual employee, their disability and their needs in their particular job,” Ostrowski said. “For safety sensitive roles I’d recommend a policy that tells employees who have a medical need for marijuana, that they must notify their employer, so they can look at the evidence and assess the person’s ability to do the job safely.”

An individualized policy, as opposed to a blanket one, could help employers avoid running into Human Rights problems down the line.

What about drug testing?

Drug testing in Canada is a highly contentious issue and there are very limited circumstances where an employer can make workers take one – generally only if there’s a connection between drug and alcohol testing and workplace safety. Even then an employer would have to show that there’s reasonable cause for testing.

“If there was an ongoing substance abuse problem in the workplace and there had been an accident that employees had been involved in, potentially because of this substance abuse, then testing may be justified,” Ostrowski explained. “But there would have to be a demonstrated safety problem or threat in the workplace and even then the employer can’t necessarily test everyone. It would be limited to those who had been involved in the accident.

How can employers be prepared ahead of the Cannabis Act?

Proactively instill your marijuana related policy sooner rather than later, addressing both medical and recreational use individually. Be specific about where medical use can take place, can it be used on site? If so, where? And when? Are employees allowed smoke at work? Or are they only allowed to use it in edible form?

Be explicit in your policy, specify how, and to what extent both medical and recreational use will be tolerated, if at all in the case of the latter.

“Certainly employers should have a detailed policy in place before the legislation passes so that employees have time to review it and familiarize themselves with it before it comes into effect. I certainly think any policy should require employees to disclose any marijuana prescriptions or use that might lead to impairment at work,” Ostrowski added. “The onus should be on them to let their employer know, not just after an accident has happened. Just because employers have a duty to accommodate these employees doesn’t mean they should get to consume how much they want, whenever they want, wherever they want. So the employer has to start putting those limits in place.”