As used in this subchapter, unless the context otherwise requires:
(1) “Catastrophic illness” means a medical condition, as certified by a physician, of an employee or of the spouse or parent of the employee or of a child of the employee who may be claimed as a dependent under the Income Tax Act of 1929, § 26-51-101 et seq., which requires an employee's absence from duty for a prolonged period of time and which, except for the catastrophic leave program, would result in a substantial loss of income to the employee because of the exhaustion of all earned sick and annual leave;
(2) “Catastrophic leave” means leave granted to an employee as a result of a catastrophic illness, upon the employee's exhausting of all sick and annual leave;
(3) “Catastrophic leave bank” means a pool of accrued annual leave donated by employees; and
(4) “Employees” means nonfaculty nonclassified personnel employed by a state institution of higher education.