The Subchapter O Endorsement

The United States (U.S.) standards are mirrored by International Gas Code (IGC). However, there are four areas in which the Coast Guard utilized the regulatory process to establish additional requirements designed to increase liquefied gas carrier safety. These standards focus on areas of the vessel’s containment system and hull construction, such as: (1) hull material; (2) cargo tank pressure and temperature control; (3) maximum allowable relief valve settings; and (4) ambient design temperatures. The Coast Guard verifies compliance using a combination of plan review and physical examination. A successful plan review leads to the Coast Guard developing a “Subchapter O endorsement” (SOE) for carriage of specific cargoes, which is issued after the vessel successfully undergoes a certificate of compliance (COC) exam. These documents allowed the Marine Safety Center to verify compliance with the standards that are not found in the IGC and ensure that Coast Guard responders have the necessary drawings on file to respond to a potential gas carrier incident in a U.S. port. Once the vessel successfully completes a certificate of compliance exam, the operator will receive the Subchapter O endorsement and certificate of compliance.


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Filing Info

  • Accession Number: 01609047
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 29 2016 7:45AM