The Civil Service Act shall only apply to full-time firefighters or full-time police officers of each municipality, including any paid full-time police chief or fire chief of such department. All appointments to and promotions in such department shall be made solely on merit, efficiency, and fitness, which shall be ascertained by open competitive examination and impartial investigation. If the appointing authority fills a vacancy in a position subject to the Civil Service Act, the appointing authority shall consider factors including, but not limited to:

(1) The multiple job skills recently or currently being performed by the applicant which are necessary for the position;

(2) The knowledge, skills, and abilities of the applicant which are necessary for the position;

(3) The performance appraisal of any applicant who is already employed in the department, including any recent or pending disciplinary actions involving the employee;

(4) The employment policies and staffing needs of the department together with contracts, ordinances, and statutes related thereto;

(5) Required federal, state, or local certifications or licenses necessary for the position; and

(6) The qualifications of the applicants who are already employed in the department and have successfully completed all parts of the examination for the position. No person shall be reinstated in or transferred, suspended, or discharged from any such position or employment contrary to the Civil Service Act.