Navigational guidance and warnings

You can get navigational information by radio from: navigational warnings, broadcast on either NAVTEX or Inmarsat SafetyNET NAVAREA (I) warnings, broadcast through EGC SafetyNET UK coastal navigational warnings broadcast on VHF and MF on selected aerials at 4-hourly intervals Read more about maritime safety broadcast times and medical advice calls . In-force navigational warnings are shown on the UK Hydrographic Office ( UKHO ) website. Reporting navigational hazards You may get warnings about: damaged or broken lights, fog signals, buoys and navigational aids that affect main shipping lanes wrecks, reefs, rocks and shoals that might be a danger to main shipping lanes drifting hazards, such as derelict ships, mines, ice unexpected changes or closures of established routes cable or pipe laying, naval exercises or underwater operations that might be a danger for shipping lanes problems with radio navigation, radio or satellite maritime safety information services areas to avoid where search and rescue and anti-pollution activities are happening Contact the United Kingdom Hydrographic Office ( UKHO ) Radio navigational warning helpline if you’ve spotted any of these hazards or want to ask about them. UKHO Radio navigational warning helpline navwarnings@ukho.gov.uk Telephone: 01823 353 448 Find out about call charges You’ll have to contribute toward the cost of broadcasting any necessary warnings if you’re responsible for causing a navigational hazard.

Safe navigation is particularly important in adverse weather and sea conditions. Read more about keeping a safe navigational watch on merchant ships . Navigation lights, shapes and sound signals Your ship must comply with the requirements for navigation lights and other equipment in the ‘Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations’ . Restricted visibility Read information on navigating in restricted visibility . High-speed craft Read information on controlling high-speed craft in adverse sea conditions . Navigating in the Dover Strait The Dover Strait is one of the busiest shipping lanes in the world. The Dover Strait Traffic Separation Scheme ( TSS ) exists to help ships crossing the Dover Strait to navigate safely and avoid collisions. Read information about the TSS and guidance for ships in the Dover Strait . The Dover Strait and Channel Navigation Information Service ( CNIS ) The Dover CNIS provides a 24-hour radio and radar service for all shipping in the Dover Strait. Dover CNIS broadcasts information in the Dover TSS area every 60 minutes (30 minutes if visibility drops below 2 miles). You can find these on VHF radio channel 11. Dover CNIS broadcasts information on: weather and sea conditions navigational hazards, like hampered vessels misplaced or defective navigational aids deep draught bulk carriers and tankers vessels under tow surveying vessels unorthodox crossings, such as cross-channel swims Information is also broadcast about any ship that appears to be breaking the International Regulations for the Prevention of Collisions at Sea to warn other ships of a potential hazard. Ships using the TSS are automatically tracked by radar. This information can be used in a prosecution if any ship breaks the law.

Voyage data recorders

A voyage data recorder ( VDR ), often known as the ship’s ‘black box’, collects and stores information over the course of a ship’s journey, including: the ship’s position audio from the ship’s bridge the ship’s speed and heading depth under the keel VHF radio communications All VDRs must be tested after installation and then inspected every year. Find out more about the requirements for voyage data recorders .

The Global Maritime Distress and Safety System

The Global Maritime Distress and Safety System ( GMDSS ) is a maritime communications system used for: emergency and distress messages vessel-to-vessel routine communications vessel-to-shore routine communications If you own commercial ships with over 300 gross tonnage, or certain smaller craft, fit them with GMDSS equipment. Most offshore yacht races also now insist that competing yachts are GMDSS -equipped. Read the Merchant Shipping (Radio Installations) Regulations for more information on who has to fit GMDSS . Digital Selective Calling ( DSC ) for pleasure craft It’s voluntary for small leisure craft to have GMDSS , but HM Coastguard strongly recommends that pleasure craft install GMDSS with DSC . DSC is a tone-signalling system with the ability to include other information like: a vessel’s identification number the purpose of the call your position the channel you want to speak on

A 406 megahertz ( MHz ) beacon can send a distress signal via satellites to alert search and rescue authorities to your location. There are 3 types: Emergency Position Indicating Radio Beacons ( EPIRBs ) for vessels Emergency Locator Transmitters ( ELTs ) for aircraft Personal Locator Beacons ( PLBs ) for personal use You must register your beacon and keep your registration up to date .

Navigation equipment for small commercial vessels

Small commercial ships should keep a listening watch on VHF channel 16 for any coastguard announcements. You should fit VHF DSC (Digital Selective Calling) if your ship needs a fixed VHF channel to receive these broadcasts. All new vessels and all those replacing VHF radios must have VHF DSC installed. Radio installation You must mount any radio aerials as high as you can to get the best possible reception. If your main aerial is fitted to a mast, you should also provide an emergency aerial. Contact the Maritime and Coastguard Agency ( MCA ) if you’re not sure of the VHF coverage in the area where you’ll be operating. MCA radio helpline Telephone: 02380 329356 Find out about call charges You must make sure that you’re able to charge the batteries that charge the ships’ radio equipment and that they’re protected from flooding. Your fixed radio installation should be marked with: the ship’s call sign codes for the use of the radio Maritime Mobile Service Identity ( MMSI ) number (where applicable) You should also have a card giving information on radio distress, urgency and safety procedures in full view of the radio operating position. Navigation lights, shapes and sound signals Your ship must meet the requirements of the Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations . Small vessels may be exempt from certain requirements, for example if: you only operate between sunrise and sunset or in favourable weather, in which case you do not have to carry navigation lights your vessel is less than 12 metres in length, in which case you do not have to carry sound signalling equipment Read the rules in section 17 of MGN 280 on navigation lights, shapes and sound signals for small commercial vessels . Rules for other navigational equipment are detailed in section 18.

Maritime safety: weather and navigation

Q: Weather and tide information

Weather information at sea Find information about conditions at sea from The Met Office provides useful information about conditions at sea, including: a shipping forecast and gale warnings marine observations which give information on wave height, visibility and sea temperature Longer-term weather outlooks You can get an extended outlook with information up to 5 days in advance on the 518 NAVTEX service. Information about tides The UK Hydrographic Office provide information on tides through the Admiralty Easy Tide Service .

Maritime Safety Information broadcasts

HM Coastguard regularly broadcasts Maritime Safety Information (MSI) by radio. MSI includes:

information on wind strength and direction
warnings of restricted visibility
updates on sea conditions
navigational guidance and warnings

MSI broadcasts may be interrupted or delayed due to search and rescue operations.

You must check MSI and other weather and tide information to avoid collisions and accidents at sea. You must also make sure that you understand any navigational guidance or warnings that are broadcast to your ship.

How to receive MSI

MSI is broadcast:

by NAVTEX (Navigational telex) out to 270 miles
on VHF out to 30 miles
on MF out to 150 miles

Read the Maritime and Coastguard Agency (MCA) guide to maritime safety information, which includes information on broadcast frequencies.

View a printable version of the whole guide

Maritime safety: weather and navigation

Maritime Safety Information broadcasts

How to receive MSI

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Maritime safety: weather and navigation

Maritime Safety Information broadcasts

How to receive MSI

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