(1) Waterproof test. The searchlight shall be subjected for 5 minutes to a stream of water under a head of approximately 35 feet from a hose not less than 1 inch in diameter from a distance of approximately 10 feet. The hose nozzle shall be adjusted to give a solid stream at the enclosure. No leakage shall occur in this test.

(2) Beam candlepower. All light except that produced from the searchlight under test shall be excluded from the room in which measurements are made. The searchlight shall be operated at rated voltage with a seasoned lamp as specified in § 161.006-4(e). Measurements of beam candlepower shall be made at the corners of a 6-inch square located in the center of the beam at a distance of 32 feet immediately in front of the searchlight.

(3) Corrosion resistance. The searchlight shall be subjected to a 200-hour salt spray test in accordance with ASTM B 117 (incorporated by reference, see § 161.006-1). There shall be no evidence of corrosion that will be detrimental to the operation of the searchlight.

(4) Heat run. The searchlight, completely assembled, shall be operated continuously for 2 hours at rated voltage following which the waterproof test shall be conducted. This cycle shall be repeated 3 times. The ambient temperature shall be approximately 25 °C. The water stream shall be from an ordinary cold water tap.