Hello-
Two questions- First, can an employer refuse to count a vacation day towards an employees 40 hour weekly total, preventing the employee from earning overtime until he has accrued 48 hours? Say Monday vacation day, tuesday thru friday 8 hours worked, saturday 8 hours worked. This is 48 hours total, which my employer pays as straight time.

Second question, is there a set amount that an employer must pay for being "on-call"? Both on call pay and for the hours worked (ex. 4 hour minimum)??

Employers do not have to include paid hours in the calculation of hours for the purposes of overtime. They must only count hours worked. So, the practice you describe is legal (and quite common).

In response to your second question, employers do not need to compensate employees for time when they are on-call, unless the employee is very restricted in being able to utilize his/her time. For example, if the employee is contacted by a pager or his/her cell phone if he/she is needed. Otherwise, the employee can go shopping, see a movie, sleep, etc., then that does not have to be considered paid time. However, the employee must be compensated for the time when he/she actually responds to the call/page. There is no minimum amount that must be paid.

Let me know if you have any other questions.