The UK Marine Accident Investigation Branch (MAIB) has blamed inadequate maintenance for the accidental release of carbon dioxide on two ro-ros.
It said that fortunately no one was hurt in the incidents, but that the unintended release of CO2 from fire-extinguishing systems caused 72 deaths and 145 injuries, mainly in the marine industry, between 1975 and 2000.
The first incident occurred on 8 June 2016, when AW Ship Management's 13,300-gt ro-ro Eddystone (built 2002) experienced a release from its fixed fire-extinguishing system while on passage in the Southern Red Sea.
A similar incident then took place on 17 July 2017 on board Red Funnel's 4,100-gt ro-pax Red Eagle (built 1996) while it was en route from the Isle of Wight to Southampton.
In both cases, the engine room distribution valve for the carbon dioxide gas remained closed and gas leaked out into the compartment where the carbon dioxide cylinders were stored, MAIB said.
Maintenance vital
Malfunctioning cylinder valves were the cause, MAIB added.
"It is almost certain that the CO2 fire-extinguishing system on Eddystone discharged because of one or more incorrectly torqued Schmole cylinder valve set screws," MAIB said.
The unintended release of CO2 on Red Eagle was caused by one or more cylinder valves leaking into the manifold, causing the system to discharge, it added.
Accidents on board two of Eddystone’s sister vessels were also reported to the MAIB, but these did not result in investigations.
The MAIB investigation revealed that maintenance had been inadequate, and that the available guidance on the maintenance and inspection of carbon dioxide fixed fire-extinguishing systems was insufficient.
In 2004, the release of five tonnes of CO2 on board the Hong Kong-registered containership YM People killed the vessel’s master, chief engineer, chief officer and third engineer.
The Maritime and Coastguard Agency (MCA) has issued a safety bulletin to the operators of all UK-registered vessels regarding appropriate maintenance.
AW Ship Management and Red Funnel have replaced the components that contributed to these incidents on the sister vessels in their fleets.
Red Funnel has been recommended to review the design of the carbon dioxide fire-extinguishing systems fitted to its ships where the leakage of a single cylinder valve causes the entire system to discharge.
