Insurance union publishes recommendations on safe carriage of electric vehicles

The firefighting effort on the vehicle carrier Höegh Xiamen after a blaze ignited on board while the ship was off Jacksonville, Florida, on June 4, 2020. The National Transportation Safety Board said the fire was traced to an improperly disconnected battery on one of the embarked vehicles. (Photo: Jacksonville Fire and Rescue Department)

There are growing concerns within the shipping community, including marine underwriters, about fires breaking out on car carriers and Ro-Ro vessels with the assertion that many of these fires are attributable to electric vehicles. In response, the International Union of Marine Insurance (IUMI) has researched these claims and published recommendations on the safe carriage of electric vehicles (EVs).

“Our paper draws on a body of scientific research that demonstrates that fires in battery EVs are not more dangerous than fires in conventional vehicles, nor are they more frequent,” Lars Lange, IUMI Secretary General, explains. “Although statistics continue to be gathered, they currently estimate that, in general, there are fewer fires from EVs  compared with fires from conventional vehicles when driven over the same distance.”

Research also proves that there is only a minor difference between total energy released during an EV fire and one that is related to an internal combustion engine vehicle (ICEV). Once established, vehicle fires are largely (approximately 80 per cent) fuelled by the car body and interior parts rather than the propulsion system.

However, the potential for thermal runaway (when the battery suffers an unstable chemical reaction) exists for EVs whereas it is not a consideration for ICEVs. Thermal runaway makes fires hard to extinguish, hence mitigation measures such as boundary cooling must be employed rapidly.

Moreover, the risk of re-ignition is higher for an extended period of time.

In the paper, IUMI makes important distinctions between Ro-Ros and pure car and truck carriers (PCTCs), noting that many Ro-Ros will stow cars on open decks where air flow makes firefighting more challenging. Ro-Pax vessels (where passengers are also carried) present additional issues such as passengers wanting to charge onboard and the possibility of loading cars that are older and potentially less safe.

Conversely, PCTCs tend to carry vehicles tightly packed leaving little room for emergency access and facilitating the rapid spread of a fire.

In light of this, IUMI concludes:

  • Early fire detection and verification/confirmation is critically important to reduce the time between detection and firefighting response to a minimum. Options, in addition to the conventional systems, could include thermal imaging cameras and AI-powered systems.
  • Drencher systems are effective for firefighting onboard Ro-Ro and Ro-Pax vessels both for EV and ICEV fires and should be installed alongside video monitoring systems.
  • CO2 extinguishing systems, if applied quickly, are successful in fighting PCTC fires and their capacity should be doubled. High-expansion foam fire extinguishing systems have also proved to be effective to prevent heat transfer from one vehicle to another.
  • Early detection, confirmation, and a short response time are crucial to fight a fire successfully. On board PCTCs, fixed systems should always be applied before manual firefighting is employed.
  • A clear policy is required on which cargo is accepted or rejected. Vehicles should be screened with used vehicles being checked carefully for hidden damage.
  • Charging on board Ro-Pax vessels should be permitted subject to relevant risk assessments and control measures. Safety mechanisms built into EVs are usually activated during charging.

The IMO’s Sub-Committee on Ship Systems and Equipment (SSE) will start work on the “Evaluation of adequacy of fire protection, detection and extinction arrangements in vehicle, special category and ro-ro spaces in order to reduce the fire risk of ships carrying new energy vehicles” beginning in March 2024.

The full IUMI paper is available here.

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