1. 1. Notwithstanding the provisions of any law to the contrary, and only for the purpose of computing retirement benefits provided by an established retirement plan, after five years' service, any condition of impairment of health caused by any disease of the lungs or respiratory tract, hypotension, hypertension, or disease of the heart resulting in total or partial disability or death to a uniformed member of a paid fire department, who successfully passed a physical examination within five years prior to the time a claim is made for such disability or death, which examination failed to reveal any evidence of such condition, shall be presumed to have been suffered in line of duty, unless the contrary be shown by competent evidence.
2. 2. This section shall apply to paid members of all fire departments of all counties, cities, towns, fire districts and other governmental units.

(L. 1969 p. 157 § 1)