Keynote speaker at a health unit luncheon told companies there's no good test for impairment yet.

The Windsor Essex County Health Unit wants businesses to be prepared for the legalization of recreational marijuana.

It brought in a speaker Wednesday to speak to companies over the lunch hour.

"It's a timely and relevant topic that has implications for just about every workplace and the scenarios will be different everywhere depending on the kind of work," said Neil Mackenzie, manager of chronic disease and injury prevention with the health unit.

Already on the radar

Centerline was one of the companies attending and it says this is already on its radar.

The major danger is operating any kind of equipment. People working in safety sensitive positions. They will be unaware that they're still under the influence coming to work on a Monday morning so that would be concerning to us," said Karl Mroczkowski, training and safety coordinator with Centerline.

He said his team is rewriting policies already and waiting to see what will be in the final legislation.

"I think we're going to have to tell [workers]. We all need to communicate and get on the same page to understand what our obligations are to [workers] and their obligations to us and their fellow employees, their colleagues, their coworkers," he said.

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No testing for impairment

The speaker warned companies that there may be good tests for the presence of drugs in a person's body but there are no good tests for impairment.

"When someone eats marijuana — the edibles — it will take anywhere from 30 to 90 minutes for someone to feel the effects and you can see how that would be a problem in a workplace," said Randy Herman, who works with CannAmm Occupational Testing Services.

Meanwhile, a medical marijuana patient in the audience said she hopes businesses will be even-handed with employees and will differentiate between people like her and recreational users.

"Presently, there are people that are using it and obviously it's in secret and their employers aren't aware of it," Pat Copus told reporters after the key note speech. "There's a lot of people being weaned off of opiates, which are far more dangerous, and we have an opiate crisis here in Windsor. So it's important for those people to be educated that when they're coming off opiates and onto cannabis that they're going to be supported by their employer."