46 U.S.C. § 7103: Licenses for radio officers

(a) A license as radio officer may be issued only to an applicant who has a first-class or second-class radiotelegraph operator license issued by the Federal Communications Commission. (b) Except as provided in section 7318 of this title, this part does not affect the status of radiotelegraph operators serving on board vessels operating only on the Great Lakes.