Management of collision risk - Radio communication between offshore installations, their standby vessels and merchant ships

  • Operations notice: 61
  • Issue date: Apr 2003


1. The Health and Safety Executive has become aware of several recent incidents where installations, or their attendant standby vessels, have been unable to establish radio communication with a vessel on a collision course with the installation.

2. Further examination of these incidents has shown that there were a number of reasons why difficulty was experienced in establishing communications. However, it has become clear that radio procedures used to establish communications with the approaching vessels are often not correct,in that the initial calling was made on VHF Channel 16.


3. Between 1992 and 1999, new international procedures for alerting marine distress were phased in and, from 1 February 1999, all passenger and cargo vessels greater than 300 gross tonnage must comply with all applicable requirements of the Global Maritime Distress and Safety System (GMDSS).

4. GMDSS is an international system which uses terrestrial and satellite technology and ship-board radio systems to ensure rapid, automated, alerting of shore-based communication and rescue authorities, as well as ships in the immediate vicinity, in the event of marine distress.

5. GMDSS was adopted by the International Maritime Organisation (IMO) via its Safety of Life at Sea (SOLAS) 1988 convention. The implementation of GMDSS is the responsibility of individual contracting governments that have ratified the requirements into their national law. In the UK, GMDSS was implemented via the Merchant Shipping (Radio Communications) Regulations 1998.

6. Under the new GMDSS procedures, distress, urgency and safety alerts are made in a significantly different manner than before. Such alerts are not made by voice, but digitally via digital selective calling (DSC) equipment, on different frequencies (on VHF the alerting frequency is now channel 70). After communication is established the parties would change to a distress working frequency, which on VHF is channel 16. Ship-to-ship communication is to be conducted on VHF channel 13. By further amendment, the IMO has determined that ships subject to SOLAS are to maintain a continuous watch where practicable on VHF channel 16, until 1 February 2005.

7. GMDSS applies to vessels, which would include those mobile installations registered as vessels. All offshore installations that operate on the UK continental shelf (UKCS) are required to comply with the Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995 (PFEER). These Regulations require that, among other things, the dutyholder makes suitable arrangements for the purpose of emergency response, for communication between the installation and people beyond it. In addition to PFEER, regulation 12 of the Offshore Installations and Pipeline Works (Management and Administration) Regulations 1995 (MAR) requires that dutyholders have effective means of communication between the offshore installation and the shore, vessels, aircraft and other installations in place.


8. Dutyholders on all installations are advised to verify that communication hardware, procedures and training meet the requirements of the applicable regulations, for both their installations and other rescue facilities that they may contract. Although the GMDSS applies to vessels, other installations needing to communicate with vessels in their vicinity at times of distress or urgency should be aware of the agreed GMDSS procedures. The correct method for making a distress or urgency alert on VHF is to transmit the relevant DSC alert on channel 70, subsequent communication would proceed on channel 16 or channel 13.


  • A guide to the Offshore Installations and Pipeline Works (Management and Administration) Regulations 1995. Guidance on Regulations L70 (Second edition) HSE Books 2002 ISBN 0 7176 2572 9
  • Prevention of fire and explosion and emergency response on offshore installations. Offshore Installations (Prevention of Fire and Explosion and Emergency Response) Regulations 1995. Approved Code of Practice and guidance L65 HSE Books 1997 ISBN 0 7176 1386 0
  • Safety of Life at Sea (SOLAS) Convention Consolidated edition International Maritime Organization 2001 available on-line at International Maritime Organization

Further information

Any queries relating to this notice should be addressed to:

Health and Safety Executive
Hazardous Installations Directorate
Offshore Division
Lord Cullen House
Fraser Place
AB25 3UB

This guidance is issued by the Health and Safety Executive. Following the guidance is not compulsory and you are free to take other action. But if you do follow the guidance you will normally be doing enough to comply with the law. Health and safety inspectors seek to secure compliance with the law and may refer to this guidance as illustrating good practice

Updated 2021-11-04