The National Post reports in its Friday, June 7, edition that Canadian airline and flight crews are forbidden to consume cannabis for at least 28 days before going on duty, the country's transportation regulator said on Thursday. A Reuters dispatch to the Post reports that Transport Canada's new policy, which is effective immediately, says no person should work while "under the influence of any drug that impairs the person's faculties to the extent that aviation safety is affected," according to statement that was posted on its website. Four weeks is the minimum time required to be free of cannabis before being allowed to work, according to the aviation regulator. The new rules do not prevent airlines or airports from requiring even stricter requirements of their employees. Canada became the first developed country in the world to legalize cannabis in October, 2018. Since then, various industries have issued guidelines around cannabis use. The aviation regulator said the move aligns with scientific consensus on drug usage while on the job and the Department of National Defence and RCMP'S policies on cannabis.