46 C.F.R. § 161.013-7 Signal requirements.
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(a) An electric light must have a flash characteristic of the International Morse Code for S-O-S and, under design conditions, (1) Each short flash must have a duration of (2) Each long flash must have a duration of 1 second; (3) The dark period between each short flash must have a duration of (4) The dark period between each long flash must have a duration of (5) The dark period between each letter must have a duration of 2 seconds; (6) The dark period between each S-O-S signal must have a duration of 3 seconds. (b) The flash characteristics described in paragraph (a) must be produced automatically when the signal is activated.
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PART 161—ELECTRICAL EQUIPMENT
Subpart 161.013—Electric Distress Light for Boats
§ 161.013-7 Signal requirements.
