I don't really have the answer to your question.
But, I am working at a Dominion gas turbine outage near Trenton, NJ.
The Dominion folks are asked to do alot of different things.
One employee could do maintenance, labor, IH, safety, and other tasks all in one day. These guys stay hoppin' on this job.
I can ask some of the In-Housers about your question.