The dire consequences of a tunnel fire became evident when a transport truck caught fire as it was driving through the Mont Blanc tunnel between Italy and France on March 24, 1999. Other vehicles pulled up. found trapped and firefighters could not reach the transport truck. Thirty-nine people died.
Responding to a tunnel fire successfully relies on an ability to use resources efficiently, manage the incident scene, understand the dynamics of tunnel fires, and learn from past fires.
Best practice in tunnel firefighting emphasizes pre-incident planning. Firefighters need to understand the dynamics of fires in tunnels and the systems that will affect those dynamics. The necessary elements include conducting and maintaining pre-fire plans, better communication and a more in-depth study of methods of fighting fires in tunnels.
Each tunnel requires a pre-fire plan, including information on access, water supply, ventilation and coordination of response efforts. Radio communication with tunnel managers can ensure accurate information exchange with incoming fire units in the event of a fire.
Standard operating procedures are vital, along with training exercises to maintain readiness
A cooperative working relationship with the surrounding agencies guarantees a mutual response in the event of a fire in a tunnel. A policy should incorporate a common response and identify the primary and secondary responsibilities of each department depending on the situation. Standard operating procedures are vital, as are training exercises to maintain readiness.
In the event of a fire in a tunnel, alternative transport measures should be put in place to minimize any economic impact.
Technology is a component of fire risk management in tunnels. For example, a linear heat detection system above the carriageway in the Blackwall tunnel in London is an improvement on the tunnel fire detection system.
In the event of a fire, tunnel ventilation systems are designed to push smoke forward through the tunnel, assuming that traffic will stop behind the fire site.
However, driver behavior is an additional variable. For example, drivers may continue to walk past a fire rather than stopping. In this case, a larger fire could produce thicker smoke that could overwhelm conductors before they reach the end of the tunnel. Fire systems may need to be reconsidered based on more research into human behavior.
Brighter, whiter lights will improve incident site management and increase visibility for drivers
Visibility is also an important part of emergency management inside tunnels. For example, high pressure sodium (HPS) lamps have been replaced by 1,174 LED lamps along the EastLink tunnels in Victoria, Australia. Brighter, whiter lights will improve incident site management and increase visibility for drivers compared to “orange” HPS lights.
The Saltash Tunnel in the UK has deployed state-of-the-art technology to keep the thousands of people safe on the 410-meter underground track in Cornwall. An incident detection system enables faster and more responsive detection of vehicle fires and other incidents.
Emergency escape signs and separate smoke and heat detection systems are aligned with the public address system to direct drivers to the safest exit in the event of an incident in the tunnel. Drivers are quickly alerted and emergency services can react more quickly in the event of a potential incident via a control room.
A more realistic approximation of a real fire scenario helps improve tunnel safety
Hot smoke demonstrations, which create realistic scenarios to enable responders to improve their responses to a real emergency, are a preparation tool for possible tunnel fires. Demonstrations are safe for people and infrastructure and minimize business disruption. A more realistic approximation of a real fire scenario helps improve tunnel safety.