11 CAR § 11-802
(a) Generally.
(2) The determination involves:
(3) Facts may show that:
(b) On duty.
(3)
(c) Off duty.
(2) He or she is not completely relieved from duty and cannot use the time effectively for his or her own purposes unless he or she is definitely told in advance that he or she:
(d) On-call time.