46 CFR 138.315: External audits for a TSMS certificate
Last reviewed: October 14, 2026
This section requires external audits, conducted through a TPO, to obtain and renew a TSMS certificate. The audits must include both management and vessels. The section also sets timing for each audit and requires audit results to be documented and kept.
Applies toOwners or managing operators who obtain or renew a TSMS certificate, and the vessels subject to their TSMS.
What it says
Before an owner or managing operator receives an initial TSMS certificate or a renewal, an auditor from a TPO must conduct an external management audit.
46 CFR 138.315(a)(1)“an external management audit must be conducted by an auditor from a TPO.”
A mid-period external management audit must be conducted between the 27th and 33rd month of the certificate's period of validity.
46 CFR 138.315(a)(2)“A mid-period external management audit must be conducted between the 27th and 33rd month of the certificate's period of validity.”
Vessels subject to the TSMS that were owned or operated for 6 or more months before receiving the initial COI must have an external audit before the initial COI is issued.
46 CFR 138.315(b)(1)“An external audit must be conducted prior to the issuance of the initial COI for vessels subject to an owner or managing operator's TSMS that have been owned or operated for 6 or more months prior to receiving the initial COI.”
Vessels subject to the TSMS that were owned or operated for fewer than 6 months before receiving the initial COI must have an external audit no later than 6 months after the initial COI is issued.
46 CFR 138.315(b)(2)“An external audit must be conducted no later than 6 months after the issuance of the initial COI”
All vessels covered by a TSMS certificate must be externally audited during the 5-year period of validity. The vessels must be selected randomly and distributed as evenly as possible.
46 CFR 138.315(b)(3)“The vessels must be selected randomly and distributed as evenly as possible.”
External audits may use objective evidence that may be available at the corporate office, but some portions require visiting each vessel at some point during the 5-year period of validity.
46 CFR 138.315(b)(4)“Some portions of this audit require visiting each vessel at some point during the 5-year period of validity of the TSMS certificate.”
The results of the external audit must be documented and kept for 5 years. They must be made available to the Coast Guard or the external auditor upon request.
46 CFR 138.315(c)“The results of the external audit must be documented and maintained for a period of 5 years and made available to the Coast Guard or the external auditor upon request.”
Common questions
When is the mid-period external management audit due?
It must be conducted between the 27th and 33rd month of the TSMS certificate's period of validity.
“A mid-period external management audit must be conducted between the 27th and 33rd month of the certificate's period of validity.”
How long must TSMS external audit results be kept?
The results must be documented and maintained for 5 years. They must be made available to the Coast Guard or the external auditor upon request.
“The results of the external audit must be documented and maintained for a period of 5 years and made available to the Coast Guard or the external auditor upon request.”
How are vessels chosen for the external audit during the TSMS certificate period?
All vessels covered by the certificate must be audited during the 5-year period of validity. They must be selected randomly and distributed as evenly as possible.
“The vessels must be selected randomly and distributed as evenly as possible.”
The text of 46 CFR 138.315
Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR
External audits for a TSMS certificate
External audits for obtaining and renewing a TSMS certificate are conducted through a TPO and must include both management and vessels as follows:
(a) Management audits. (1) Prior to the issuance of an owner or managing operator's initial TSMS certificate, or subsequent renewals, an external management audit must be conducted by an auditor from a TPO.
(2) A mid-period external management audit must be conducted between the 27th and 33rd month of the certificate's period of validity.
(b) Vessel audits. (1) An external audit must be conducted prior to the issuance of the initial COI for vessels subject to an owner or managing operator's TSMS that have been owned or operated for 6 or more months prior to receiving the initial COI.
(2) An external audit must be conducted no later than 6 months after the issuance of the initial COI for vessels subject to the owner or managing operator's TSMS that have been owned or operated for fewer than 6 months prior to receiving the initial COI.
(3) An external audit of all vessels covered by a TSMS certificate must be conducted during the 5-year period of validity of the TSMS certificate. The vessels must be selected randomly and distributed as evenly as possible.
(4) External audits may include the use of objective evidence which may be available at the owner or managing operator's corporate office. Some portions of this audit require visiting each vessel at some point during the 5-year period of validity of the TSMS certificate.
(c) Documentation. The results of the external audit must be documented and maintained for a period of 5 years and made available to the Coast Guard or the external auditor upon request.
Guides that cite this section
The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.