As used in the firefighters relief act:
(a) "Firefighters relief association" or "firemen's relief association" means an association incorporated under the laws of this state composed of members of a fire department which is (1) a public fire department under the control of the governing body of an incorporated city, township, county or fire district or (2) a private fire department operated by a not-for-profit corporation which provides all of the fire protection services for an incorporated city, township, county or fire district pursuant to a contract with the governing body thereof, and which in either case has fire apparatus and necessary equipment therefor that is in serviceable condition for fire duty and has a value of $5,000 or more; and
(b) "insurance company" means every company, corporation, firm or association transacting the business of fire insurance in this state.