Code of Federal Regulations Title 33. Navigation and Navigable Waters § 33.67.10–1 Apparatus requirements

(a) Have its maximum intensity at a frequency between 100 and 1,100 Hertz;

(b) Sound a 2–second blast every 20 seconds (2 seconds sound, 18 seconds silence) unless otherwise authorized by the District Commander;

(c) Have the rated range required by § 67.20–10, § 67.25–10, or § 67.30–10;

(d) Have a height not exceeding 25 feet;

(e) Have not more than eight sound sources;

(f) Be approved by the Coast Guard under § 67.10–15;  and

(g) Be permanently marked with: