47 U.S. Code § 353a - Operators and watches on radiotelephone equipped ships

(a)
Each cargo ship which in accordance with this part is equipped with a radiotelephone station shall, for safety purposes, carry at least one operator who may be the master, an officer, or a member of the crew.
(b)
Each cargo ship of the United States which in accordance with this part is equipped with a radiotelephone station shall, while being navigated in the open sea outside of a harbor or port, maintain continuous watch whenever the station is not being used for authorized traffic.
(June 19, 1934, ch. 652, title III, § 354, as added Aug. 13, 1954, ch. 729, § 2(b), 68 Stat. 706; amended Pub. L. 89–121, § 5, Aug. 13, 1965, 79 Stat. 514.)
Amendments

1965—Pub. L. 89–121 substituted “radiotelephone station” for “radiotelephone installation” in two places, and “one operator who may be the master, an officer, or a member of the crew” for “one qualified operator who may be a member of the crew holding only a certificate for radio telephony”, inserted “in the open sea” before “outside of a harbor”, and required a continuous watch whenever the station is not being used for authorized traffic.