Section 136.105 - Applicability(a) This subchapter is applicable to all U.S.-flag towing vessels as defined in § 136.110 engaged in pushing, pulling, or hauling alongside, except-(1) A vessel less than 26 feet (7.92 meters) in length measured from end to end over the deck (excluding the sheer), unless that vessel is pushing, pulling, or hauling a barge that is carrying oil or hazardous material in bulk;(2) A vessel engaged in one or more of the following:(i) Assistance towing as defined in § 136.110 ;(ii) Towing recreational vessels for salvage; or(iii) Transporting or assisting the navigation of recreational vessels within and between marinas and marina facilities, within a limited geographic area, as determined by the local Captain of the Port (COTP);(3) A workboat operating exclusively within a worksite and performing intermittent towing within the worksite;(4) A seagoing towing vessel of 300 gross tons or more subject to the provisions of subchapter I of this chapter;(5) A vessel inspected under other subchapters of this chapter that may perform occasional towing;(6) A public vessel as defined in 46 U.S.C. 2101 ;(7) A vessel that has surrendered its COI and is laid up, dismantled, or otherwise out of service; and(8) A propulsion unit used for the purpose of propelling or controlling the direction of a barge where the unit is controlled from the barge, is not normally manned, and is not utilized as an independent vessel.