(a) This subpart applies to all towing vessels subject to this subchapter.

(b) Except as noted paragraph (c) of this section, which lists later implementation dates for requirements in §§143.450 and 143.460, an existing towing vessel must comply with the applicable requirements in this part no later than either July 20, 2018 or the date the vessel obtains a Certificate of Inspection (COI), whichever date is earlier. The delayed implementation provisions in this section do not apply to a new towing vessel.

(c) Existing vessels must meet the pilothouse alerter and towing machinery requirements of §§143.450 and 143.460 no later than 5 years after the issuance of the first COI for the vessel.