Section 143.515 - Towing vessels built to recognized classification society rules(a) Except as noted in paragraph (c) of this section, a towing vessel classed by the American Bureau of Shipping (ABS), in accordance with the ABS Rules for Building and Classing Steel Vessels Under 90 Meters (295 Feet) in Length, or the ABS Rules for Building and Classing Steel Vessels for Service on Rivers and Intracoastal Waterways (incorporated by reference, see § 136.112 of this subchapter), as appropriate for the intended service and routes, complies with this subpart.(b) Except as noted in paragraph (c) of this section, a towing vessel built and equipped to conform to the ABS rules specified in paragraph (a) of this section and appropriate for the intended service and routes, but not currently classed, may be deemed by the OCMI or a TPO to be in compliance with this subpart if it can be shown that the vessel continues to conform to the ABS rules.(c) A vessel that complies with this subpart as described in paragraph (a) or (b) must also meet the requirements described in §§ 143.585 through 143.595 or the requirements of § 143.600 if it moves tank barges carrying oil or hazardous material in bulk.(d) Vessels meeting either paragraph (a) or (b) of this section are considered as being in compliance with subpart B of this part except for the readiness and testing requirements of § 143.245 , and pilothouse alerter requirements of § 143.450 .(e) Towing vessels built to other recognized classification society rules, appropriate for the intended route and service, may be considered compliant with provisions in this subpart upon approval by the Coast Guard.