We speak with Pascal Blanc, Tunnel Safety Project Manager, about the training exercises designed to prepare operators and emergency services for potential emergencies in road tunnels. While such incidents are thankfully rare, being ready for them is essential!
How often should you do emergency drills in road tunnels, and why?
Drills should take place at least once a year, and often operators will decide to conduct two within the year. Fortunately, major events like fires or accidents involving multiple vehicles are rare, but that means that we have few opportunities to apply procedures. So, it's essential to make sure we know them and test them.
How do you prepare an emergency drill?
Preparing a drill involves several months of work with a small group of people. First, we define what we want to test: a new piece of equipment, a new procedure, a rarely applied procedure, or the reorganisation of a department, with three or four objectives. Only at this stage do we create the scenario of the event to be simulated. A drill is not improvised, and we learn as much from preparing it as from executing it.
What specific risks associated with road tunnels make emergency drills particularly important?
As a road tunnel operator, we must ensure maximum safety in the structures. The risks we prepare for include accidents of varying severity in the tunnels and the total or partial loss of safety equipment, like cameras or fire doors, for example. In case of accidents or fires, we must protect the victims, alert emergency services, and assist them. Tunnel incidents like fires, crashes or breakdowns produce confined smoke and toxic fumes, making evacuation and emergency response especially challenging.
Sometimes, the design of the tunnel might impede access and evacuation. Also, the technical systems in tunnels - ventilation, lighting, communication, and firefighting systems - are all crucial for safety. Coordinating their operation during incidents needs prepared responders. This involves activating the right equipment in the correct order. Our first action is to protect by activating closure barriers to prevent users from entering the tunnel. We then activate the firefighting system and set the ventilation and lighting to their maximum levels. Next, we alert the fire department, ambulance services, police, and the operator’s internal teams.
To protect the environment from potential pollution, we close the retention basins. This measure is designed to contain any chemical or contaminated liquids, whether resulting from an accidental spill in the tunnel or from water used during firefighting efforts.
By closing the basin valves, we prevent these liquids from spreading into the environment. Instead, they are securely contained for subsequent pumping and treatment by a specialised company. And this must be done in the shortest possible time. Therefore, training is essential. As for the loss of equipment, it can impair our ability to safely operate the tunnel, and if we are unable to operate safely, we close the tunnel.
What are the risk factors for equipment, and what measures do you take to prevent equipment loss?
The pollution conditions and aggressive atmosphere in tunnels due to CO2 and de-icing salt put equipment under significant stress, hence the need for preventive maintenance, where equipment is regularly replaced. Cameras are typically replaced every 15 years; fire doors every 20 to 25 years. By contrast, the emergency call station motherboard is replaced at least every other year, enabling updates with the latest technologies.
How do you incorporate these equipment failure situations into your emergency drills?
We train to apply procedures, particularly the Minimum Operation Condition (MOC), to mitigate potential equipment failures. Suppose several consecutive cameras are out of service; we must still ensure that information is transmitted to the control centre in case an accident occurs in the same area. We regularly train to manage events such as a traffic accident happening in front of a faulty camera. An exercise is a test of the procedures and equipment, which allows us to determine whether the safety equipment is functioning properly or if the procedures accurately describe what needs to be done, in the correct order.
Which teams are involved in emergency drills?
We train by pulling in all operator and emergency services: police, firefighters, ambulance and all the teams that aren't visible when driving through the tunnel. It largely depends on the chosen scenario, but generally, all operational teams are involved: control room operators, patrol officers, repair crews, maintenance staff, on-call personnel, in addition to emergency services. A drill involves multiple actors, and each must coordinate with the others. Knowing each other's roles is essential.
How does communication among various teams impact the effectiveness of an emergency drill in a tunnel?
It is crucial that several services in full action exchange the right information, at the right time. We train to communicate effectively through rephrasing and validating the transmitted information. This brings clarity and precision to exchanged information and prevents information loss or misinterpretation.
Can you provide an example of an emergency drill that directly contributed to saving lives or preventing a disaster in a road tunnel?
A small clarification: a drill doesn't directly save lives. However, as a training exercise, it helps maintain a high level of vigilance and knowledge among all tunnel safety actors. Recently, we conducted a safety drill in the Bosphorus Tunnel to verify the proper application of new procedures for managing an event involving an electric vehicle. With the increase in electric vehicles, it is crucial to understand the new risks they pose and know how to manage them.
How are lessons learned from past drills integrated into future safety strategies?
In France, the Tunnel Studies Centre (CETU) has established a guide for conducting drills, emphasising the importance of the debrief phase, which involves evaluating the drill. For me, a successful drill is one after which we upgrade our equipment and update our procedures. There is always an action plan established after the drill. A drill that wouldn’t challenge our practices would be too easy.
How is the effectiveness of an emergency drill in a road tunnel measured?
Effectiveness is measured by achieving the three or four objectives set during the drill preparation, but not only that. As mentioned, the extent of the action plan is also indicative of the drill's success.
