Using an inappropriate space as workshop and to store propane gas and paint resulted in an explosion on a dry cargo vessel. The Nautical Institute describes the incident in a new Mars Report.
The Nautical Institute gathers reports of maritime accidents and near-misses. It then publishes these so-called Mars (Mariners’ Alerting and Reporting Scheme) Reports (anonymously) to prevent other accidents from happening. This is one of these reports.
A dry cargo vessel in ballast was underway in strong winds and rough seas. At around 2100, when the vessel was approximately 35 nautical miles from shore, there was an explosion in a forward compartment.
The explosion tore open parts of the forward mooring deck. All five cargo hatch covers were dislodged; two hatch covers fell into the sea, while the remaining three collapsed into the empty cargo hold. Simultaneously, the vessel suffered an electrical power outage, but the main engine continued to function.
The crew quickly broadcast a distress call over VHF radio, which was received by a coast station, and a rescue operation involving several ships and two rescue helicopters was initiated. The entire crew were hoisted to safety by one of the rescue helicopters approximately one hour and 45 minutes after the incident. The vessel then drifted, abandoned, for two days, before being towed to a port of refuge. No one was physically injured in the incident, but the damage was so extensive that the vessel was declared a total constructive loss and scrapped.
Also read: Vapour migration to bow thruster compartment causes explosion
Investigation findings
The investigation revealed that the explosion was caused by propane gas leaking and igniting in a forward compartment. The general lack of space on the vessel meant that any available space was used on an ad hoc basis, and this compartment had been gradually converted into a workshop and paint storeroom. Several different products ended up in the same forward space, including two cylinders of propane with a total of 22 kg of gas.
The investigation found, among other things, that neither the crew nor the shipping company had identified that the space was unsuitable for these purposes, since it lacked proper ventilation and appropriate access routes. The space was also connected to the cargo hold, which meant that if oxygen depleting cargo was carried, the space could have been rendered oxygen deficient and so become a lethal trap for crew.
Also read: Explosion in bow thruster compartment
Advice from The Nautical Institute
- Propane and other flammable gases must never be stored in makeshift workshops or paint lockers. Hazardous materials require dedicated, certified storage areas that are physically isolated from potential ignition sources.
- Ventilation is non-negotiable. Any compartment used for chemical or gas storage must have adequate, independent ventilation to prevent the buildup of explosive atmospheres or oxygen-depleted air.
- Changing the use of a compartment (for example, converting a void space into a workshop) requires a formal management-of-change process to identify new risks, such as lack of access routes or connection to cargo holds.
- The crew’s rapid distress call and successful evacuation highlight the importance of functional emergency procedures and communication equipment during a “total loss” event.
- The investigation noted that the shipping company failed to identify the risks. Safety Management Systems should include regular audits specifically looking for unauthorised or unsafe storage practices in non-standard spaces.
Also read: Onboard paint storage slip up
Mars Reports
This accident was covered in the Mars Reports, originally published as Mars 202622. A selection of the Mars Reports are also published in the SWZ|Maritime magazine. The Nautical Institute compiles these reports to help prevent maritime accidents. That is why they are also published (in full) on SWZ|Maritime’s website.
More reports are needed to keep the scheme interesting and informative. All reports are read only by the Mars coordinator and are treated in the strictest confidence. To submit a report, please use the Mars report form.
