(a) The commissioners court may adopt rules and prescribe procedures and forms relating to the operation of the county sick leave pool program. The commissioners court by rule may require an employee to:
(1) enroll in the county sick leave pool as a condition for eligibility under Section 157.075(a); and
(2) transfer at least one day of accrued sick leave time or, if allowed under Section 157.072(b), accrued vacation leave time earned by the employee as a condition of enrollment.
(b) The commissioners court shall designate a person to administer the county sick leave pool program.
(c) The commissioners court shall determine which injuries and illnesses are classified as catastrophic for purposes of this subchapter. The court shall provide to the administrator a written statement of that classification.