Channel 16 on a VHF marine radio is reserved for distress or Mayday calls involving an imminent threat to life or immediate peril involving a vessel’s seaworthiness. Channel 16 channel, along with 9 and 13, can also be used for less-urgent Pan-Pan (non-emergencies) and Sécurité (public service) calls.
Spending time on the open water is one of the most relaxing and satisfying ways to enjoy the great outdoors. But being on a boat also means that you are potentially far removed from aid if an emergency occurs.
A VHF marine radio is an essential resource for requesting assistance but is there a channel reserved for distress calls?
Whether you are out for a leisurely sail or embarking on a major voyage, knowing how to request help while out on a boat can be the difference between being rescued and or suffering tragedy.
Keep reading to learn why a VHF radio may be your only means of communication during an emergency and which channels represent your best chance of getting the aid you need.
What VHF Marine Radio Channel Is Reserved for Distress Calls?
Even though we live in a digital world and handheld communication devices have never been more powerful, if you are thrust into an emergency situation while at sea, your cell phone may not be the best option for getting help. Cellular signals will not transmit in weak signal areas and no communication will occur unless the receiving party picks up your call.
A VHF (very high frequency) marine radio is the go-to communication device for boaters and sailors, particularly while navigating coastal waters. When powered on, a VHF marine radio provides an on-demand, instantaneous means of communicating with other boats, marinas, bridges, and perhaps most importantly, the United States Coast Guard.
For emergencies involving injury to a person or serious damage to the vessel, use Channel 16 (156.8 MHz) on your VHF marine radio to place a distress call and request immediate aid. Listeners on that channel, including the US Coast Guard and other boaters, will understand that people or the boat are facing grave and imminent danger (i.e., a “mayday” situation).
Here is a list of all VHF Marine radio channels and their reserved purposes. You can also download a pdf version of this for future reference.
|VHF Channel Number
|Port Operations (not in all areas)
|Bridge-to-Bridge Navigation (ship to ship)
|Reserved for Environmental (not for boater use)
|Distress, Safety and Calling
|Data (not for voice)
|U.S. Coast Guard
|Coast Guard Liaison & Maritime Safety Info Broadcasts
|U.S. Coast Guard
|Public Correspondence (Marine Operator)
|Port Operations (in select areas)
|Digital Selective Calling (DSC) (not for voice)
|Non-Commercial (Intership only)
|Port Operations (Intership only)
|U.S. Coast Guard
|Public Correspondence (Marine Operator)
|Non-Commercial (Sarcastic Regions)
How Do You Make a Distress Call From a Boat?
Even with painstaking boat maintenance and meticulous trip planning, unexpected difficulties can arise while you are boating or sailing. There are three categories of communication used to notify other parties of a potentially dangerous condition or to request aid: (1) Mayday, (2) Pan-Pan, and (3) Sécurité. Each of these corresponds to differing levels of urgency and it is important to know when they should be used.
Mayday calls are made on the aforementioned Channel 16 and are used only in cases involving dire circumstances, such as serious injury to a person or significant damage to the vessel. Because VHF marine radio communications must be brief and to the point, Mayday calls should follow a prescribed format to relay vital information as effectively as possible.
Here is an example script showing how a Mayday call should be placed:
- Tune your VHF marine radio to Channel 16 and clearly state the word MAYDAY three times
- State the name of your vessel three times including your boat registration number once
- Describe your location as accurately as possible, either with a latitudinal or longitudinal position or your proximity to a familiar landmark (the objective is to allow a responding vessel to reach you as quickly as possible)
- Briefly explain your emergency and the type of aid you require (e.g., a fire onboard and all occupants must evacuate immediately into a life raft)
- State the number of people onboard
- End your transmission with the word OVER
The US Coast Guard recommends staying near your VHF marine radio following your Mayday call in case you need to clarify or update your location while assistance is en route.
A Pan-Pan (pronounced pahn-pahn) call is used to request assistance with situations that are serious but not life-threatening or involving the immediate seaworthiness of the vessel. Typical situations calling for a Pan-Pan transmission include:
- Your vessel is adrift, due to a failed propulsion or navigation system
- A person has fallen overboard but is in sight and not in imminent threat of harm
- You have an onboard mechanical problem, such as a minor leak, falling short of dire straits but requiring assistance
A Pan-Pan call should follow the same format as a Mayday call and may be placed on Channel 16, but the transmission should be kept short to keep the frequency clear of traffic for Mayday emergencies.
The third, and least urgent, type of distress call is known as a Sécurité (pronounced sea-cur-i-tay). This serves as an advisory to other vessels and is used to warn others of:
- Potential hazards, such as objects floating in the water
- Adverse weather conditions
- Heavy or unusual traffic involving other vessels
Sécurité calls are often made as a courtesy to other vessels and represent goodwill among boaters and sailors.
Using VHF Marine Radio Channel 16 Properly
Channel 16 on a VHF marine radio is reserved for making distress calls, the most important type of communication transmitted on the open water. Because of its critical role in preserving life and property, Channel 16, and other frequently used channels, such as 13 and 22A, need to be kept as congestion-free as possible.
For this reason, boaters are encouraged to respect the following communication protocols and rules of etiquette:
- Channel 16 is reserved for emergencies involving an imminent threat to life or property and should not be used for less-urgent situations (there are other channels for such calls)
- Be brief and to the point, and when asked, switch to a different channel to minimize radio traffic on Channel 16 and other vital frequencies (Channel 9 is commonly used as an alternate radio channel following initial contact on Channel 16)
- For communications of a non-urgent nature, particularly between pleasure craft and recreational vessels, utilize channels 68 and 72
- Regardless of the channel, extended conversations will prevent other users from broadcasting on the same frequency so keep all communications short and on point
- Be mindful that other vessels within a 20-mile radius can listen in on any communication, including children and people who may take offense to foul language and inappropriate comments
VHF radio technology relies on line-of-sight transmissions, meaning that its signals travel in a straight line. While this allows for instantaneous communication among vessels within 20 miles of each other, it also means that these common radio channels must be shared and rules of etiquette respected.
Whether you are anchored a few hundred yards offshore or drifting miles from the nearest coastline, an onboard emergency requires swift action to get the help you need. Knowing how to make a Mayday distress call on a VHF marine radio can make all the difference in the world when you are faced with a situation where every second counts.