Saying "man" is really colloquial and should be avoided if the proper job title is obvious. (Lots of jobs have "man" in their official title, milkman, rag and bone man, etc).
New2grammarThe door man
Doorman is a person that stands outside a disco or nightclub and controls entry, but, context is everything, so if you were to say (with your hand on a door), "
the door man is coming to fix this on Tuesday" it would sound perfectly natural and no one would think about the nightclub. Whether the others are ok really depends on the ear of the listener but they sound ok to me, except "light man" should be "lighting man". This could be taken to be an electrician or a man in a film studio that controls the way the film set is illuminated.