Canadian driving laws impacting cannabis users. Do you know the limits?

The government of Canada recently announced that they have selected Drager 5000 as the first device for doing roadside test for Cannabis and a few other substances. This decision was approved by Attorney General Jody Wilson-Raybould, with a goal to uphold the penalties defined in Bill C-46. This device is to be used by officers after someone is pulled over and there is suspicion that they may be under the influence of a substance.