If a construction worker is drunk at a construction site.?

Who should be held responsible? A friend told me the worker should take the responsible for doing this and not the Foreman. I told her that if the foreman see's the person is drunk, he should send him home or fire him (if he doesn't, than the foreman is responsible). She thinks I'm wrong and that the foreman can't perform a breathalyzer on every worker. But, she told that her husband said that the worker was apparently drunk. Lawyers out there what's you opinion?