Applicability: shipowners, ship operators, ship managers and ship masters.

The Republic of Marshall Islands Maritime Administration (RMI) has issued Marine Safety Advisory notice No. 14-23 for bursting discs in carbon dioxide (CO2) fire extinguishing systems. 

The notice advises about the failure of CO2 cylinder valves that were manufactured by NK Co. Ltd, Korea prior to 2016. 

It was found that the total number of empty or partially empty fixed CO2 system cylinders represented a loss of more than 50% of the ship’s available supply. The root cause analysis determined that the variable environmental conditions and fluctuating air cylinder pressures led to a material failure of the copper bursting discs in the cylinder valves.

In 2016, the cylinder valve’s manufacturer changed the material in the bursting discs from copper to nickel, which is more resistant to changing environmental conditions. Although NK Co. Ltd, Korea did not issue a service bulletin or similar notice recommending the replacement of copper bursting discs with nickel bursting discs in cylinder valves, they have since updated their User Manual.

What should shipowners and managers do now?

Ship owners, managers and operators of vessels are advised to review the following requirements and recommendations:

  • For all fixed fire-extinguishing systems, shipowners/operators should verify with the manufacturer that it meets the recommended material component requirements and any required changes. Where the manufacturer’s maintenance manuals and inspection guidelines exist, they need to be available on board and followed. (For RMI-flagged vessels, they need to be in accordance with RMI Marine Notice 2-011-14, Maintenance and Inspection of Fire Protection Systems and Appliances.) 

  • For systems with NK Co., LTD, Korea cylinder valves, the instructions in the updated User Manual need to be followed. 

  • It is strongly urged that owners/operators implement their periodic review process of manufacturer’s system manuals, service bulletins and notices to ensure system changes can be identified, implemented and rectified.

A summary of the SOLAS Requirements for Maintenance, Servicing, Testing and Drills can be downloaded here.

Further support and information 

For further information or advice, please get in touch with your local Lloyd's Register office or contact

Download PDF of Class News 19/2023