My employer a public hospital is trying to mandate everyone work 12hr a week extra. I understand their need to pay overtime for overtime hours worked. But I am a part time employee therefore I wouldn't reach 40 hr to get overtime pay. This is a solution to alliviate short staffing, not what I was hired for. It would be a hardship for out family to have me do this so I need to see what the legalities are. Can they make me work more hours than I was hired for (years ago) and nothing more than straight pay.

Short of a contract to the contrary, they can require you to work whatever hours business necessity requires. The fact that you were hired as part-time several years ago doesn't mean they can't change that going forward. The fact that the extra hours will not put you into an overtime situation not withstanding.

Nothing in Federal law, the laws of North Carolina, or the laws of 45 other states require that you be paid overtime unless you work 40 hours or more in the work week. Although four states (none of the North Carolina) require that overtime be calculated on a daily basis, no law in any state requires that you be paid overtime because you are working more hours than originally hired for.

Patty has given you the correct answer; unless you have a bona fide contrat that guarantees your hours will never change, they can legally require that you work as many hours as they need you to work, and unless you work more than 40 hours in a work week, they need not pay you overtime.