There are no rules or laws regarding FT or PT employees in any industry. It is up to the employer or other players.
Our insurance company says you have to be FT (average 32 hours per week for the month) to qualify for coverage. But that does not mean you do 32 hours of massage per week -- a near physical impossibility.
We require our FT therapists to be on the schedule and available for work 40 hours per week. That does not mean we are required to pay them for the 40 hours they are available.
YOu seem to have posted several times on different topics that seem related, without divulging the full story.
What are you getting at?