Code of Federal Regulations Title 50. Wildlife and Fisheries § 50.300.336 Vessel identification

(i) A vessel must be marked with its international radio call sign (IRCS) or, if not assigned an IRCS, must be marked (in order of priority) with its Federal, state, or other documentation number appearing on its high seas fishing permit and, if a WCPFC Area Endorsement has been issued for the vessel under § 300.212, that documentation number must be preceded by the characters “USA” and a hyphen (that is, “USA–”);

(ii) The markings must be displayed at all times on the vessel's side or superstructure, port and starboard, as well as on a deck;

(iii) The markings must be placed so that they do not extend below the waterline, are not obscured by fishing gear, whether stowed or in use, and are clear of flow from scuppers or overboard discharges that might damage or discolor the markings;

(iv) Block lettering and numbering must be used;

(v) The height of the letters and numbers must be in proportion to the size of the vessel as follows:  for vessels 25 meters (m) and over in length overall, the height of letters and numbers must be no less than 1.0 m;  for vessels 20 m but less than 25 m in length overall, the height of letters and numbers must be no less than 0.8 m;  for vessels 15 m but less than 20 m in length overall, the height of letters and numbers must be no less than 0.6 m;  for vessels 12 m but less than 15 m in length overall, the height of letters and numbers must be no less than 0.4 m;  for vessels 5 m but less than 12 m in length overall, the height of letters and numbers must be no less than 0.3 m;  and for vessels under 5 m in length overall, the height of letters and numbers must be no less than 0.1 m;

(vi) The height of the letters and numbers to be placed on decks must be no less than 0.3 m;

(vii) The length of the hyphen(s), if any, must be half the height (h) of the letters and numbers;

(viii) The width of the stroke for all letters, numbers, and hyphens must be h/6;

(ix) The space between letters and/or numbers must not exceed h/4 nor be less than h/6;

(x) The space between adjacent letters having sloping sides must not exceed h/8 nor be less than h/10;

(xi) The marks must be white on a black background, or black on a white background;

(xii) The background must extend to provide a border around the mark of no less than h/6;  and

(xiii) The marks and the background must be maintained in good condition at all times.