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Radio Watchkeeping Regulations

A charter boat whose radio was not tuned to the proper channel missed a severe storm warning. By the time the captain learned of the storm, it was too late to return to shore. The ship sank and a couple of persons died. A yacht in trouble off the west coast of Mexico and far from help saw a passenger ship. What should have been a quick rescue could have turned to disaster when the passenger ship (improperly) had its radio off. The yacht was able to attract the ship's attention, however, and was rescued. Misunderstanding of passing intentions by approaching vessels and near collisions have repeatedly been averted by working radios tuned to the proper channel.

Who regulates whom?

Three U.S. government agencies, the Federal Communications Commission, the National Telecommunications and Information Administration, and the U.S. Coast Guard; and two international organizations, the International Telecommunications Union and the International Maritime Organization; have each established marine radio watch keeping regulations. Regulations on radio watch keeping exist for all boats and ships --commercial, recreational, government and military, domestic and foreign-- carrying marine radios.

International Telecommunications Union (ITU). ITU regulates all use of radio spectrum by any person or vessel outside U.S. waters. ITU rules affecting radio, which have treaty status in the U.S. and most other nations, are published in the ITU Radio Regulations. The ITU has established three VHF marine radio channels recognized worldwide for safety purposes:

  • Channel 16 (156.800 MHz) - Distress, safety and calling
  • Channel 13 (156.650 MHz) - Intership navigation (bridge-to-bridge)
  • Channel 70 (156.525 MHz) - Digital Selective Calling

International Maritime Organization (IMO). IMO regulates the outfitting and operation of most vessels engaged on international voyages, except warships. Most IMO radio regulations affect all passenger ships and other ships of 300 gross tonnage and upward. IMO rules affecting radio are promulgated in the Safety of Life at Sea (SOLAS) Convention which has been ratified in the U.S.

Federal Communications Commission (FCC) - the FCC regulates all sales, marketing, and, use of radios in the U.S., including those onboard any recreational, commercial, state and local government, and foreign vessel in U.S. territorial waters. These regulations are contained in Title 47, Code of Federal Regulations.

National Telecommunications and Information Administration (NTIA) - NTIA regulates all use of radio onboard any federal government vessel, including military vessels. NTIA rules do not apply outside the federal government.

U.S. Coast Guard (USCG) - The USCG regulates carriage of radio on most commercial vessels, foreign vessels in U.S. waters, survival craft, and vessels subject to the Bridge-to-Bridge Act (generally all vessels over 20m length) and operating in a Vessel Traffic Service (VTS) area.

Radio Watchkeeping Regulations

In general, any vessel equipped with a VHF marine radiotelephone (whether voluntarily or required to) must maintain a watch on channel 16 (156.800 MHz) whenever the radiotelephone is not being used to communicate.

Source: FCC 47 CFR §§ 80.148, 80.310, NTIA Manual, ITU RR 31.18, 52.244

In addition, every power-driven vessel of 20 meters or over in length or of 100 tons and upwards carrying one or more passengers for hire, or a towing vessel of 26 feet or over in length, as well, as every dredge and floating plant operating near a channel or fairway, must also maintain a watch on channel 13 (156.650 MHz) --channel 67 (156.375 MHz) if operating on the lower Mississippi River-- ; while navigating on U.S. waters (which include the territorial sea, internal waters that are subject to tidal influence, and, those not subject to tidal influence but that are used or are determined to be capable of being used for substantial interstate or foreign commerce). Sequential monitoring techniques (scanners) alone cannot be used to meet this requirement; two radios (including portable radios, i.e. handhelds) or one radio with two receivers, are required. These vessels must also maintain a watch on the designated Vessel Traffic Service (VTS) frequency, in lieu of maintaining watch on channel 16, while transiting within a VTS area. See 33 CFR §§ 2.36, 26, and 161; 47 CFR §§ 80.148, 80.308-309; NTIA: NTIA Manual Chapter

Digital Selective Calling

Ships, where so equipped, shall, while at sea, maintain an automatic digital selective calling watch on the appropriate distress & safety calling frequencies [e.g. channel 70] in the frequency bands in which they are operating. If operating in a GMDSS Sea Area A1 may discontinue their watch on channel 16. However, ships, where so equipped, shall also maintain watch on the appropriate frequencies for the automatic reception of transmissions of meteorological and navigational warnings and other urgent information for ships.

Ship stations complying with these provisions should, where practicable, maintain a watch on the frequency 156.650 MHz for communications related to the safety of navigation.

ITU RR 31.18, 25.244