Section 15.535 - Towing vessels(a)Applicability. Except as provided in this paragraph (a), the requirements in this section apply to a towing vessel subject to subchapter M of this chapter. Vessels subject to this section must also meet the requirements in § 15.515(c) . A towing vessel at least 8 meters (26 feet) in length, measured from end to end over the deck (excluding sheer), that is not subject to subchapter M must meet the requirements in paragraph (b) of this section if it is- (1) A seagoing towing vessel of 300 gross tons or more subject to the provisions of subchapter I of this chapter;(2) A vessel inspected under other subchapters of this chapter that may perform occasional towing; or(3) A public vessel as defined in 46 U.S.C. 2101 .(b)Towing vessels 8 meters or more in length. Every towing vessel of at least 8 meters (26 feet) in length, measured from end to end over the deck (excluding sheer), must be under the direction and control of a person holding a MMC endorsed as master or mate (pilot) of towing vessels or as master or mate of vessels of greater than 200 gross register tons, holding a completed Towing Officer Assessment Record signed by a designated examiner indicating that the officer is proficient in the operation of towing vessels upon the appropriate route.(c)Towing Vessels of Any Length on the Lower Mississippi River. In addition to the requirements of paragraph (b) of this section, any towing vessel operating in the pilotage waters of the Lower Mississippi River must be under the control of an officer who holds either a first-class pilot's endorsement for that route, or MMC officer endorsement for the Western Rivers, or who meets the requirements of either paragraph (c)(1) or (2) of this section, as applicable. (1)Moving tank or hazardous material barges. To operate a towing vessel with tank barges or a tow of barges carrying hazardous material regulated under subchapter N or O of this chapter, the officer in charge of the towing vessel must have completed at least 12 round trips over this route as an observer, with at least 3 of those trips during hours of darkness, and must provide evidence to the Coast Guard upon request that at least 1 of the 12 round trips occurred within the last 5 years.(2)Moving uninspected barges or no barges. To operate a towing vessel without barges or a tow of uninspected barges, the officer in charge of the towing vessel must have completed at least 4 round trips over this route as an observer, with at least 1 of those trips during hours of darkness, and must provide evidence to the Coast Guard upon request that at least 1 of the 4 round trips occurred within the last 5 years.USCG-2006-24412, 81 FR 40100, June 20, 2016