46 C.F.R. § 13.505 Proof of service for “Tankerman-Engineer” endorsement.
Title 46 - Shipping
(a) Service must be proved by a letter on company letterhead from the owner, operator, master, or chief engineer of a tankship or self-propelled tank vessel. The letter must specify— (1) The classification of cargo (DL, LG, or both) carried while the applicant accumulated the service; and (2) The number of days of licensed and unlicensed service in the engine department on tankships or self-propelled tank vessels; or (b) Service must be proved by certificates of discharge from tankships or self-propelled tank vessels with the appropriate classification of cargo (DL, LG, or both). [CGD 79–116, 60 FR 17142, Apr. 4, 1995, as amended by CGD 79–116, 62 FR 25135, May 8, 1997]
Title 46: Shipping
PART 13—CERTIFICATION OF TANKERMEN
Subpart E—Requirements for “Tankerman-Engineer” Endorsement
§ 13.505 Proof of service for “Tankerman-Engineer” endorsement.

