Fire protection systems inside the Channel Tunnel urgently need upgrading and open sided wagons should be banned from freight trains. These calls come from a leading civil engineer and a fire brigade spokesman following Saturday’s fire on board a train carrying heavy goods vehicles.

Imperial College senior research fellow Professor Dr Gabriel Alexander Khoury, who specialises in tunnels, concrete and fire, said that a thermal barrier should be fitted to the inside of the Channel Tunnel to protect the integrity of the structure.

“Explosive spalling of concrete is a major risk with tunnel fires, which can reach 1000 degrees within five minutes,” he told TP Weekly News. “Concrete can be protected by installing a passive protection system such as a thermal barrier, which is in place inside the Dublin port tunnel.”

“There have already been two major fires in the Channel Tunnel in 1996 and 2008. Damage in 1996 was estimated at £200M to the concrete and rail and rolling stock plus lost revenue. Following the 2008 fire lost revenue alone was £185M.

“Years ago I calculated the cost of a thermal barrier was about £50M. However, the cost of installing a thermal barrier was deemed too expensive.”

Fire Brigade Union executive council member Jim Parrott added: “I do not believe that the safety measures are right inside the tunnel. I would prefer to see only closed sided vehicles used, because open sided wagons can fan the flames.”

A Eurotunnel spokesman said that use of a fire suppression system including new ‘safe stations’ underground allow the driver of a train on fire to make a controlled stop and for mist to be targeted directly at the source. “Open sided wagons mean that the fire can be dealt with more easily,” he said.

Saturday’s fire was minor compared to previous Channel Tunnel fires, such as in 2008 when hundreds of metres of tunnel lining were destroyed which took several months to rebuild. By contrast the rebuild this time will take a day or two, the spokesman added.

Inspectors from the Office of Rail Regulation are looking into what happened on the English side and French authorities are leading on the investigation as the fire broke out closer to France. The Department for Transport said that the Rail Accident Investigation Branch is making preliminary enquiries in conjunction with BEA-TT, its French counterpart.

The Eurotunnel spokesman was asked if the installation of further safety systems would now be considered. “We will rule nothing out, every option will be considered,” he said. “Our goal is to have a safe and secure site and to minimise risk.”