46 CFR 13.405: Proof of service for Tank Vessel-Assistant endorsement

Last reviewed: October 14, 2026

This section says how service is proved for a Tank Vessel-Assistant endorsement. Service must be proved by either evidence from the owner, operator, or Master in a method prescribed by the Coast Guard, or Certificates of Discharge plus a letter on company letterhead.

What it says

  1. Service must be proved by one of two methods: evidence under paragraph (a), or Certificates of Discharge and a letter under paragraph (b).

    “Service must be proved by either—”

  2. Under the first method, the evidence must come from the owner, operator, or Master of a tankship or self-propelled tank vessel, in a method prescribed by the Coast Guard.

    46 CFR 13.405(a)“Evidence in a method prescribed by the Coast Guard from the owner, operator, or Master of a tankship or self-propelled tank vessel.”

  3. The evidence must specify the name of the vessel(s), the applicable dates, and the port(s) or terminal(s).

    46 CFR 13.405(a)(1)“The name of the vessel(s), the applicable dates, and the port(s) or terminal(s);”

  4. The evidence must specify the classification of cargo (DL or LG) carried while the applicant accumulated the service.

    46 CFR 13.405(a)(2)“The classification of cargo (DL or LG) carried while the applicant accumulated the service;”

  5. The evidence must specify the number of days of deck service the applicant accumulated on the tankship or self-propelled tank vessel.

    46 CFR 13.405(a)(3)“The number of days of deck service the applicant accumulated on the tankship or self-propelled tank vessel; and”

  6. Under the second method, proof consists of Certificates of Discharge from tankships with the appropriate classification of cargo (DL, LG, or both), plus a letter on company letterhead from the owner, operator, or Master of one of the tankships or self-propelled tank vessels.

    46 CFR 13.405(b)“Certificates of Discharge from tankships with the appropriate classification of cargo (DL, LG, or both); and a letter on company letterhead”

  7. The letter must state that the applicant has demonstrated an understanding of cargo transfers.

    46 CFR 13.405(b)(1)“An understanding of cargo transfers; and”

Common questions

How do I prove service for a Tank Vessel-Assistant endorsement?

Service must be proved by either evidence in a method prescribed by the Coast Guard, or Certificates of Discharge with a company letter. Paragraphs (a) and (b) set out each option.

“Service must be proved by either—”

What must the evidence of service say about cargo?

It must specify the classification of cargo (DL or LG) carried while the applicant accumulated the service.

“The classification of cargo (DL or LG) carried while the applicant accumulated the service;”

Who can sign the letter on company letterhead?

The letter must come from the owner, operator, or Master of one of the tankships or self-propelled tank vessels.

“a letter on company letterhead from the owner, operator, or Master of one of the tankships or self-propelled tank vessels”

The text of 46 CFR 13.405

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Proof of service for Tank Vessel-Assistant endorsement

Service must be proved by either—

(a) Evidence in a method prescribed by the Coast Guard from the owner, operator, or Master of a tankship or self-propelled tank vessel. The evidence must specify—

(1) The name of the vessel(s), the applicable dates, and the port(s) or terminal(s);

(2) The classification of cargo (DL or LG) carried while the applicant accumulated the service;

(3) The number of days of deck service the applicant accumulated on the tankship or self-propelled tank vessel; and

(4) That the applicant has demonstrated an understanding of cargo transfer and a sense of responsibility that, in the opinion of the signer, will allow the applicant to safely carry out duties respecting cargo transfer and transfer equipment assigned by the PIC of the transfer without direct supervision by the PIC; or

(b) Certificates of Discharge from tankships with the appropriate classification of cargo (DL, LG, or both); and a letter on company letterhead from the owner, operator, or Master of one of the tankships or self-propelled tank vessels stating that they have demonstrated—

(1) An understanding of cargo transfers; and

(2) A sense of responsibility that, in the opinion of the signer, will allow them to safely carry out duties respecting cargo and its equipment assigned by the PIC of the transfer without direct supervision by the PIC.

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.