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Marine Radio Could be a Lifesaver

Why Should You Have A Marine Radio On Your Boat?

You are sailing to the farthest reaches of an isolated bay when you strike an unchartered, submerged object. You begin taking on water. No one is around. If you had a radio, you could call for help.

Motoring along the river, one of your passengers begins convulsions. You know you must contact medical authorities immediately, but you are without a radio. With a radio, medical help might be only a radio call away. Without one, it may be hours before you are able to get to a medical facility.

Image of a motorboat with two antennae passing a radio station tower.

What Type Of Radio Should I Buy?

Investing in a good Very High Frequency FM (VHF FM) radio is the smartest purchase. A VHF radio has certain advantages such as:

  • Good quality transmission.

  • Strong signal.

  • Channels reserved for distress calls.

  • Continuously monitored frequencies.

Citizen Band (CB) radios are not recommended due to weak signals and overcrowded frequencies. In addition, the Coast Guard does not routinely monitor CB Channels.

Can I Use the Radio as a Telephone?

There is a marine operator in many areas, located on a specified channel, that will "patch" you into the local telephone system. A radio is not to be used for gossip or idle conversation. The use of profanity and obscene language is illegal. One difference between a telephone and a radio is that anything said over the radio will be heard by hundreds of other people. Another difference is that there are only a limited number of channels so conversation, should be kept to passing only required information. Conversation is not permitted to extend past three minutes.

What Are the Different Channels Used For?

There are 104 VHF channels designated for marine service. Of this number, 54 are designated exclusively for use in the waters of the United States. The most common channels and their purpose are listed below:

Channel 16 (156.8 MHz) This is the most important channel on the VHF band. THIS IS THE DISTRESS, SAFETY, AND CALLING FREQUENCY WHICH THE COAST GUARD MONITORS CONTINUOUSLY. All vessels equipped with VHF radios must keep their radios tuned to channel 16 so they can assist if an emergency is near. Vessels may initiate contact with each other but must shift to a working frequency to carry on a conversation (e.g., Motor vessel Albatross, this is sailing vessel Mother Goose, AB-1234, on Channel 16, switch and answer Channel 68). Use Channel 16 for only bona fide emergencies.

Channel 22A (157.1 MHz) This channel is the primary working channel of the Coast Guard. It is used for communications between the Coast Guard and the maritime public, both recreational and commercial. Severe weather warnings, hazards to navigation, and other maritime safety warnings are broadcast on Channel 22A.

Channel 13 (156.65 MHz) This channel is the bridge to bridge or "piloting" channel, used for communicating navigation information between ships. Strictly used for navigational purposes by commercial, military, and recreational vessels at locks, bridges and harbours.

Channel 6 (156.3 MHz)This channel is the ship to ship frequency used for safety related communications. This channel is not used for ordinary operational navigation or personal communications.

What Do Certain Words I Hear on the Radio Mean?

MAYDAY is a request for immediate assistance. LISTEN! DO NOT TRANSMIT!! Determine if you're in a position to help. If not, maintain radio silence. "MAYDAY" identifies an imminent, life-threatening emergency.

PAN-PAN (pronounced pahn-pahn) is used when the safety of a boat or person is in jeopardy. Man-overboard messages are sent with the PAN-PAN signal.

SECURITE (pronounced say-cure-e-tay) is used to pass navigation information or weather warnings.

What if I Hear Someone Saying MAYDAY on Channel 16?

If you have a radio and you are under way, you are required to monitor Channel 16. MAYDAY takes precedence over all other transmissions. If you hear a MAYDAY, remain silent and listen. Take down the information being passed. If the Coast Guard or other rescue authority responds, maintain silence and listen, but do not respond.

However, if there is no response, take action. Try raising the distressed vessel over the radio. Gather more information, especially the position. Attempt to raise the Coast Guard while travelling toward the vessel. Sometimes the Coast Guard may not hear the distressed vessels transmissions, but can hear another vessel near the scene; therefore, call the Coast Guard again, just in case. If you raise them, give them the information you have and follow their instructions. If you cannot contact the Coast Guard, attempt to assist the other vessel to the best of your ability without placing yourself in danger.

What If I Need Help?

If you have an imminent life threatening emergency, transmit on Channel 16:


  2. This is (name of boat three times, call letters once).

  3. Repeat once more, "MAYDAY", (your boat's name).

  4. Now report your position (give as accurate a position as possible).

  5. Report nature of emergency.

  6. Report the kind of assistance desired.

  7. Report number of people on board and condition of any injured.

  8. Description of the boat and seaworthiness.

Then wait for a response. If there is none, repeat the message.

Do I Need A Radio License or Operator's Permit?

You must have a SHIP STATION LICENSE for your radio before operation.

Transmission of a false (hoax) distress or emergency message or using obscene or profane language is illegal. If search and rescue units are sent out, the perpetrator is responsible for their costs in addition to the fine.