Sick leave with pay may be granted to regular employees in accordance with the following provisions:
(A) Sick leave shall not normally exceed the total amount credited to an employee at the time of his absence.
(B) After sick leave credits have been used, absences due to illness may be charged to annual leave, or leave without pay.
(C) Sick leave shall not be debited for absence on observed holidays or other non-work days.
('73 code, § 7-45)