I am not trying to argue or start a debate but.......it is not an electrical inspector that enforces what lisence is allowed to work for a contractor. It is the Ministry of Labour. As well.....how many times has an electrical inspector asked to see what license you posses while working for a contractor or on a job site? My guess and experience would probably tell me none. I have only been asked by the Ministry of Labour.
The facts that I have given are straight from an inspector while taking the Masters course.
442a is not regulated like a 309a. A plant is a privatly owned establishment where as in construction and maintenance (309a) you are working for contractors which in turn work in public buildings where the general public are exposed to.
Both licenses are great to have.....thats why I have both...but I am more sought after having a 309a.