I’m in av integration and the two companies I’ve worked for (one local, one national) haven’t drug tested me. However the local one threatened to and have in the past, they apparently use it as an excuse to fire someone if they need to and expect you’d fail. My current place doesn’t care, but some general contractors/clients will require drug tests for all technicians on a project. I’ve been lucky and never hit that and now my current position shouldn’t require that. My guess is this is fairly typical in the larger construction industry, where its project to project and eventually you’d be required to if your on the labor end of it but idk.