Iowa Code § 362.10: Police officers and fire fighters.

The maximum age for a regular law enforcement officer, as defined in section 80B.3, police officer, or marshal, employed full-time or part-time for police or law enforcement duties, or a paid professional fire fighter, employed full-time or part-time for the duty of fighting fires, is sixty-five years of age. This section does not apply to a reserve peace officer, as defined in section 80D.1A, or to a volunteer fire fighter.