33 C.F.R. § 151.1024 Display of number.
Title 33 - Navigation and Navigable Waters
(a) The owner or operator of each vessel under this subpart must ensure that the vessel number stated on the conditional permit issued under §151.1015 is displayed so that it— (1) Is clearly legible; (2) Has a contrasting background; (3) Is readily visible from either side of the vessel; and (4) Is in block figures that are at least 18 inches in height. (b) No person may tamper with or falsify a number required under this section.
Title 33: Navigation and Navigable Waters
PART 151—VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER
Subpart B—Transportation of Municipal and Commercial Waste
§ 151.1024 Display of number.