(a) A person may not employ or engage an individual, and an individual may not serve, in a position in which an individual is required by law or regulation to hold a Transportation Worker Identification Credential (TWIC) and/or Merchant Mariner Credential (MMC), unless the individual holds all credentials required, as appropriate, authorizing service in the capacity in which the individual is engaged or employed, and the individual serves within any restrictions placed on the credential. An individual holding an active MMC issued by the Coast Guard must also hold a valid TWIC issued by the Transportation Security Administration unless the individual is exempt under 46 CFR 10.203(b)(1).

(b) A person may not employ or engage an individual, and an individual may not serve in a position in which it is required by law or regulation that the individual hold an MMC endorsed with a national endorsement, as well as a corresponding STCW endorsement for service outside the boundary line.

(c) A person may not employ or engage an individual in a position required to hold an MMC unless that individual maintains a current medical certificate. Medical certificates must be issued and will remain current for the following periods of time, unless otherwise noted on the certificate:

(1) Two years for individuals serving on vessels to which STCW applies unless the mariner is under the age of 18, in which case the maximum period of validity will be 1 year.

(2) Five years for all other mariners.

(d) Each individual referred to in paragraph (a) of this section must hold an MMC that serves as identification, with an appropriate endorsement for the position in which the seaman serves, and the MMC, along with a valid medical certificate, must be presented to the master of the vessel at the time of employment or before signing Articles of Agreement.

(e) Each individual below the grades of officer and staff officer employed on any U.S. flag merchant vessel of 100 GRT or more must possess a valid MMC issued by the Coast Guard, except as noted below:

(1) Mariners on vessels navigating exclusively on rivers and lakes, except the Great Lakes, as defined in § 10.107 of this subchapter.

(2) Mariners below the rank of officer employed on any non-self-propelled vessel, except seagoing barges and barges to which 46 U.S.C. chapter 37 applies.

(3) Personnel not designated with any safety or security duties onboard casino vessels.

(f) Every person employed on a vessel with dual tonnages (both domestic and international) must hold a credential authorizing service appropriate to the tonnage scheme under which the vessel is manned and operating.

(a) Every seaman referred to in this section, when required, must produce a valid MMC or MMD with all applicable rating endorsements for the position sought, a valid TWIC unless the mariner is exempt under 46 CFR 10.203(b)(2), and a valid medical certificate to the master of the vessel at the time of his or her employment before signing Articles of Agreement. Seamen who do not possess one of these credentials may be employed at a foreign port or place within the limitations specified in § 15.720 of this part.

(b)(1) Every person below the grades of officer and staff officer employed on any U.S. flag merchant vessel of 100 GRT or more, except those navigating rivers exclusively and the smaller inland lakes, must possess a valid MMC or MMD, along with a valid medical certificate, with all appropriate endorsements for the positions served.

(2) No endorsements are required of any person below the rank of officer employed on any barges except seagoing barges and barges to which 46 U.S.C. chapter 37 applies.

(3) No endorsements are required of any person below the rank of officer employed on any sail vessel of less than 500 net tons while not carrying passengers for hire and while not operating outside the line dividing inland waters from the high seas. 33 U.S.C. 151.

(c) Each person serving as an able seafarer-deck, or a rating forming part of a navigational watch (RFPNW), on a seagoing vessel of 500 GT or more must hold an STCW endorsement certifying him or her as qualified to perform the navigational function at the support level, in accordance with the STCW Convention (incorporated by reference, see § 15.103 of this part).

(d) Each person serving as an able seafarer-engine, or a rating forming part of an engineering watch (RFPEW), on a seagoing vessel driven by main propulsion machinery of 1,000 HP/750 kW propulsion power or more must hold an STCW endorsement certifying him or her as qualified to perform the marine-engineering function at the support level, in accordance with the STCW Convention.

(e) Notwithstanding any other rule in this part, no person subject to this part serving on any of the following vessels needs an STCW endorsement:

(1) Vessels exempted from the application of the STCW Convention, including—

(i) Fishing vessels as defined in 46 U.S.C. 2101(11)(a);

(ii) Fishing vessels used as fish-tender vessels as defined in 46 U.S.C. 2101(11)(c);

(iii) Barges as defined in 46 U.S.C. 102, including non-self-propelled mobile offshore-drilling units;

(iv) Vessels operating exclusively on the Great Lakes; or

(v) Pilot vessels engaged in pilotage duty.

(2) Vessels not subject to any obligation under the STCW Convention due to their special operating conditions as small vessels engaged in domestic, near-coastal voyages, including—

(i) Small passenger vessels subject to subchapter T or K of 46 CFR chapter I;

(ii) Vessels of less than 200 GRT (other than passenger vessels subject to subchapter H of 46 CFR) chapter I; or

(iii) Uninspected passenger vessels as defined in 46 U.S.C. 2101(42)(B).

(a) Ratings Forming Part of a Navigational Watch (RFPNW). Each person serving as an RFPNW on a seagoing vessel of 500 GT or more, subject to the STCW Convention (incorporated by reference, see § 15.103 of this part), must hold an STCW endorsement attesting to his or her qualifications to perform the navigational function at the support level.

(b) Able seaman. Each person serving as a rating as able seaman on a U.S. flag vessel must hold an MMC endorsed as able seaman, except that no credential as able seaman is required of any person employed on any tug or towboat on the bays and sounds connected directly with the seas, or on any barges except seagoing barges or tank barges. Each person serving as an able seaman on a seagoing vessel subject to the STCW Convention must also hold an STCW endorsement as able seafarer-deck.

(c) Ratings Forming Part of an Engineering Watch (RFPEW). Each person serving as an RFPEW in a manned engineroom or designated to perform duties in a periodically unmanned engineroom, on a seagoing vessel driven by main propulsion machinery of 1,000 HP/750 kW propulsion power or more, must hold an STCW endorsement attesting to his or her qualifications to perform the marine-engineering function at the support level.

(d) Qualified Member of the Engine Department (QMED). (1) The holder of an MMD or MMC endorsed with one or more QMED ratings may serve in any unqualified rating in the engine department without obtaining an additional endorsement.

(2) A QMED may serve as a qualified rating in the engine department only in the specific ratings endorsed on his or her MMD or MMC.

(3) Persons serving on vessels subject to the STCW Convention as junior engineer, pumpman/machinist, or electrician/refrigeration engineer must also hold an STCW endorsement as able seafarer-engine.

(e) Lifeboatman. Every person assigned duties as a lifeboatman must hold a credential attesting to such proficiency. Persons serving on vessels subject to the STCW Convention must also hold an STCW endorsement in proficiency in survival craft and rescue boats other than fast rescue boats (PSC).

(f) Lifeboatman-limited. Every person assigned duties onboard a vessel that is not required to carry lifeboats and is required to employ a lifeboatman must hold an endorsement as either lifeboatman or lifeboatman-limited. Persons serving on vessels subject to the STCW Convention must also hold an STCW endorsement in proficiency in survival craft and rescue boats other than lifeboats and fast rescue boats—limited (PSC—limited).

(g) Fast rescue boats. Every person engaged or employed in a position requiring proficiency in fast rescue boats must hold an endorsement attesting to such proficiency.

(h) Entry level. Every person employed in a rating other than able seaman or QMED on a U.S. flag vessel on which MMCs are required must hold an MMD or MMC endorsed as wiper, ordinary seaman, steward's department, or steward's department (F.H.).

(i) Person in charge of medical care. Every person designated to take charge of medical care onboard vessels subject to the STCW Convention must hold an MMD or MMC endorsed as person in charge of medical care.

(j) Medical first-aid provider. Every person designated to provide medical first aid onboard vessels subject to the STCW Convention must hold an MMD or MMC endorsed as medical first-aid provider or a deck or engineer officer endorsement.

(k) GMDSS radio operator or maintainer. Every person responsible for the operation or shipboard maintenance of GMDSS radio equipment onboard vessels subject to the STCW Convention must hold an MMD or MMC endorsed as GMDSS radio operator or GMDSS radio maintainer, as appropriate.

Each credentialed crewmember must become familiar with the relevant characteristics of the vessel appropriate to his or her duties and responsibilities prior to assuming those duties and responsibilities. As appropriate, these may include, but are not limited to, general arrangement of the vessel, maneuvering characteristics, proper operation of the installed navigation equipment, proper operation of firefighting and lifesaving equipment, stability and loading characteristics, emergency duties, and main propulsion and auxiliary machinery, including steering gear systems and controls.

Every assistance towing vessel must be under the direction and control of an individual holding a license or MMC authorizing him or her to engage in assistance towing under the provisions of § 11.482 of this subchapter.