Subchapter M Regulation Details

Certificates of Inspection, the TSMS option, administrative and operational requirements, and which vessels are excluded from Subchapter M

U.S. Regulations for Towing Vessels 

Subchapter M is a part of the Code of Federal Regulations (CFR), Title 46 (Shipping), Chapter I, Parts 136 to 144. The intent of Subchapter M is to provide a unified basis to inspect towing vessels – tugboats – which had previously not been required to be regularly inspected by the United States Coast Guard (USCG). 

Subchapter M will apply to many of the towing vessels which previously were operating under Part 27 of Subchapter C – Uninspected Vessels, Towing Vessels. Subchapter M makes these vessels, except as excluded below, subject to inspections for the issuance of a Certificate of Inspection and annual survey.  Subchapter M also expands on the requirements of construction and outfitting from Part 27.  Towing vessels subject to the requirements of Subchapter I – towing vessels above 300 Gross Register Tons – are necessarily exempt from the requirements of Subchapter M as they are already inspected vessels.

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Certificate of Inspection 

The document each towing vessel must have onboard will be the Certificate of Inspection (COI), issued by the USCG. There is a phase-in period for obtaining a COI for a towing vessel, dependent on the size of the operator’s fleet. Yearly, starting on July 20, 2018 through July 19, 2022, one quarter (25%) of each towing vessel operator’s fleet subject to Subchapter M will need to have a COI at the end of the next year. Operators with a single existing towing vessel will need to have a COI not later than July 20, 2020.  

Subchapter M, Sections 136.130 and 137.202, describe the options available to a towing vessel operator for obtaining and retaining a COI. In summary, there are three means to obtain and retain a COI:

  • Have the local USCG Office(r) in Charge of Marine Inspections send a USCG inspection party (USCG Option), or
  • Have an approved Towing Safety Management System (TSMS) or equivalent, referred to as the TSMS Option and:
    • Have a survey by a Third Party Organization (TPO) or equivalent documenting the vessel condition, or
    • Have a survey by internal surveyors documenting the vessel condition, audited by a TPO.

Once a towing vessel has a COI, the vessel can operate in accordance with any limitations on the COI for a period of five years, subject to periodic inspections to maintain the COI.  If this is through the TSMS Option, periodical audit of the TSMS by a TPO will also be necessary.

SubChapter M Requirements 

There are nine parts within Subchapter M – four deal with administrative requirements for inspection and five address specific requirements for manning, operating, equipping, and constructing towing vessels. Each Part addresses a specific set of requirements:

  • Part 136 – Certification  
    This Part addresses the applicability of Subchapter M to towing vessels, how to get a certificate of inspection, and other administrative duties of the USCG.
  • Part 137 – Vessel Compliance
    This Part specifies the type of inspections, who may inspect, and what the inspections will encompass.
  • Part 138 – TSMS 
    This Part describes what a TSMS is, why an operator may choose to have a TSMS, what equivalent Safety Management Systems are, who can issue a TSMS Certificate, and how compliance of a TSMS will be evaluated.
  • Part 139 – TPO 
    This Part defines the requirements a TPO must have to be qualified to audit a TSMS, issue a TSMS Certificate, perform surveys in lieu of the USCG, and how the USCG will oversee TPO’s.
  • Part 140 – Operations  
    Requirements for operating and documenting the safe operation of a towing vessel.
  • Part 141 – Lifesaving 
    Minimum requirements for equipment onboard a towing vessel, based on its size and operating area, to save the crew in the event of abandoning the towing vessel.
  • Part 142 – Fire Protection  
    Minimum requirements for firefighting and fire prevention onboard a towing vessel.
  • Part 143 – Machinery and Electrical Systems and Equipment  
    Minimum requirements for mechanical or electrical equipment and systems onboard a towing vessel for propulsion, maneuvering, electrical control, and operational safety.
  • Part 144 – Construction and Arrangement
    Minimum requirements for the design, construction, and arrangement of towing vessels to comply with stability requirements, structural fire protection, habitability, egress and crew protection, and ventilation.

Subchapter M Exclusions

Not every ‘towing vessel’ will be required to comply with the requirements of Subchapter M – there are specific exclusions:

  1. A vessel less than 26 feet (7.92 meters) in length, unless that vessel is pushing, pulling, or hauling a barge that is carrying oil or hazardous material in bulk;
  2. A vessel engaged in assistance towing (defined in section 136.110), towing recreational vessels for salvage, or transporting or assisting the navigation of recreational vessels within and between marinas and marina facilities;
  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 Title 46;
  5. A vessel inspected under other subchapters of this chapter that may perform occasional towing;
  6. A public vessel; 
  7. A vessel that is laid up, dismantled, or otherwise out of service; or
  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.