(1) Served as a regularly qualified and commissioned chief magistrate or as the secretary-treasurer for at least eight years;
(2) Fully complied with this chapter;
(3) Terminated his or her official capacity as a chief magistrate or as the secretary-treasurer;
(4) Attained the age of 60 years;
(5) Filed with the board his or her application for such retirement, on a form to be furnished by the board, within a period of 90 days, or as soon thereafter as possible, after reaching the age of 60 years or after termination of his or her official capacity as a chief magistrate or as the secretary-treasurer, whichever may occur last in point of time; and
(6) Had his or her application for retirement approved by the board.