The presentation covered the basic characteristics of the Channel Tunnel, its risk profile and safety problems, the tunnel safety systems, the history of fire and other safety incidents with consequent measures taken, and arrangements for future operation, including new/additional train services and new rolling stock.

As most readers will know, the Channel Tunnel includes three main bores under the English Channel; two as unidirectional running tunnels of 7.6m id each and 30m apart, and a smaller service tunnel of 4.8-m diameter, usually positioned between the other two. The overall tunnel complex is approximately 50km long between portals, of which 37.5km is around 40m below the bed of the English Channel. Other major underground structures include crosspassages between the three bores, piston pressure relief ducts between the two running tunnels in an arch profile over the service tunnel, and three crossover chambers, fitted with normally closed sliding doors, for switching trains between running tunnels if necessary. The cross passages are all equipped with fireresistant doors. The piston relief ducts are equipped with dampers that, in normal operation, only open when the air pressure increases sufficiently due to train movements.

For most of their length the three bores lie in a bed of chalk marl with sets of portals at Castle Hill, Folkestone on the English side near Cheriton terminal, and at Coquelles on the French side near Sangatte and Calais. There are three main pump stations in the tunnel.

Train services
Currently the usual running tunnel traffic consists of Eurostar high-speed passenger trains running between London and the cities of Paris, Lille and Brussels, and specially designed shuttle trains running between Folkestone (Cheriton terminal) and Calais. The latter can either form tourist trains of transferrable one or two decks, depending on the heights of the vehicles, including coaches, or heavy-goods vehicles wagons with an open structure, together with a driver ‘club car’. In the central service tunnel special trackless rubber-tyre bi-directional service vehicles (STSS) run to facilitate maintenance requirements, or fire & rescue vehicles for routine patrols and emergency requirements.

In addition to these most well-known trains there are also standard freight trains (locomotives plus freight wagons, container flat cars, etc), and works trains.

Le Shuttle trains run on looped track at both terminals to change direction. For operational purposes the running tunnels are split into six zones or ‘intervals’; three in each direction. The ends of these intervals approximate to the Holywell shafts below the cliffs in England, the UK crossover chamber, the ‘French’ crossover chamber, and the French portal and crossover to the inland side of the larger Sangatte shaft. The pumps stations are located one within each interval length.

Risk profile
Tunnels are generally safe unless there is a fire, and many of Europe’s worst transport accidents have been tunnel fires. Other risks to be included in the overall profile for the Channel Tunnel cover threats to people (users and staff), national security (using the tunnel as passage), and to the fabric and equipment of the tunnel. These risks include:

• People being trapped underground in trains for long periods, perhaps resulting in panic (second only to fire).
• Conventional railway risks such as collision, derailment, signals passed at ‘danger’ (SPADS), and broken rails.
• ‘Normal’ industrial health and safety risks such as hazardous vehicle movements, and in maintenance facilities, construction work, offices and shops.
• Degradation of the infrastructure. • ‘Clandestines’ (stowaways etc).
• Security threats requiring emergency response measures.

The worst transport accidents in Europe include several major fatal tunnel fires:
• Mont Blanc road tunnel – 24 March 1999 – 39 dead.
• Tauern road tunnel – 29 May 1999 – 12 dead.
• Kaprun ski access funicular rail tunnel (Gletscherbahn 2) – 11 November 2000 – 155 dead.
• Gotthard road tunnel – 26 October 2001 – 11 dead.
• Frejus road tunnel – 5 June 2005 – 2 dead.

Incidents outside of Europe have included the Daegu metro station fire in the Republic of Korea of 18 February 2003 in which 192 people died at Jungango Station.

These incidents have been the initiators of both individual and broader initiatives to achieve improved safety.

Safety systems
In the Channel Tunnel there is a wide range of safety measures installed or in action. The service tunnel is ventilated to a higher air pressure than the running tunnels to prevent leakage of any smoke or fumes from possible incidents in the running tunnels from entering the service tunnel.

Thus the service tunnel can be regarded as a safe haven, rather than a rescue station.

At each end of the Tunnel fire brigade teams with paramedic expertise, termed FLOR (First Line of Response) are stationed, and use the previously mentioned STSS vehicles to travel the service tunnel. Whilst the FLOR crews usually stay within their ‘own end’ of the Channel Tunnel, in the event of a serious incident the emergency personnel in charge may declare that the bi-national emergency plan (BINAT) is in force. Under this the emergency teams have unrestricted access to all parts of the tunnel, irrespective of the sovereignty respected during normal operations. Thus UK and French emergency teams can, and have, cooperated to deal with serious incidents. BINAT is also a term used for the regular emergency exercises undertaken by both UK and French teams.

There are fire detection systems both in the tunnels and on the trains. Communications systems, including continuous monitoring, are installed throughout the tunnels. Train movements are monitored from two rail control centres (RCCs) at each terminal. Other protection and detection systems include automatic train protection signalling and binding brake detection.

The Shuttle trains employ tunnel-specific rolling stock with special safety design features, whilst there are specific safety rules for passenger rolling stock and tunnel operation. Emergency sidings are provided at both ends of the Channel Tunnel.

Incident history
Signing of the Treaty of Canterbury in 1986 allowed work to begin on excavating the Channel Tunnel under the UK-France agreement, including safety procedures and controls. From 1994 train services were progressively introduced including many trial runs to test systems operation, before fare-paying services commenced.

On 17 November 1996 there was a major fire starting from a truck in an HGV shuttle train that had to stop within the French section. The resultant damage to the equipment and tunnel lining required significant rebuilding during which this ‘interval’ of the tunnel had to be closed for a long period with trains, once permitted, being diverted through a crossover chamber. In addition to replacing railway and tunnel equipment the tunnel lining had to be repaired by applying steel-fibrerein forced sprayed concrete. Concrete had heat spalled from the precast lining segments, exposing the steel reinforcement cage. Extreme damage occured for a length of about 50m, with severe damage over another 240m and more minor damage over another 190m. On 21 August 2006 there was second fire, but with less serious consequences.

On 11 September 2008 there was another serious fire, this time in the ‘English action’, with major consequences. Finally, considered serious for safety due to trains being stuck underground, there was a major series of incidents on 18 and 19 December 2009 affecting five passenger trains that broke down as a consequence of cold weather conditions.

Most of these incidents involve the HGV shuttles, a service that has been affected by three fires since the opening of the Channel Tunnel in 1994. The fire of 17 November 1996 resulted in safety procedures being changed, but the last fire, on 11 September 2008, is leading to more significant changes.

It should be pointed out that in all these incidents, evacuation procedures were effective, no one was killed, and there were no significant injuries to anyone. However, there has been extensive physical fire damage requiring repair, and major disruptions to normal services.

There have been no significant fires on any other type of train.

Investigations post-2008
As results of the September 2008 fire, safety systems have been re-examined in several respects. Firstly risk assessment was revised to determine if the system is acceptably safe. In particular there has been a re-examination of the design of the HGV shuttle train rolling stock.

Eurotunnel also launched the Salamander project action plan in consultation with the Channel Tunnels Safety Authority. This took place before receipt of the BEA-TT (French Bureau d’Enquetes sur les Accidents de Transport Terrestre) report on the fire, assisted by the UK Rail Accident Investigation Branch (RAIB).

Briefly, the three elements of the Salamander project are:

• Better systems of detection and loading procedures of vehicles.
• Early intervention by fire fighters.
• Reconsideration of fire suppression or control system in the tunnel or trains.

Other subjects for investigation include a current project to examine the feasibility of, and to build in a tunnel fire suppression system. Also, as a consequence of the fire, there has been a revision of the ‘drive through’ or ‘stop and evacuate’ procedures in the event of a fire on a train.

Considerations for future
Matters requiring attention for future use of the Channel Tunnel are currently focused on the introduction of new passenger services. At the forefront of these are the requirements of the European Union Common Market ‘Open Access’ programme to allow more competition by allowing more operators through the Channel Tunnel.

The German state-owned operator Deutsche Bahn has been at the forefront of attempts to exploit the opportunity, although French organisations have objected on the basis of current Channel Tunnel safety rules on motive power construction.

These seem to be now approaching settlement, and it is likely that services to Amsterdam and northern Germany will be introduced at some stage.

At the end of 2009 Deutsche Bahn (DB) received permission to run German Intercity-Express (ICE) trains through the Channel Tunnel in the future. On 19 October 2010 Deutsche Bahn ran the first ICE train through the Channel Tunnel arriving in London St. Pancras station, after evacuation tests in the tunnel were a success.

Whatever new services are introduced it is a requirement that rolling stock is compatible with the safety rules for the tunnel, and operate with a service specification that is acceptably safe in terms of numbers of crew, training, knowledge of evacuation procedures etc.

In addition the introduction of new services will require attention to security requirements related to new operational centres, in addition to any modifications to meet with the overall international security situation.

Current rolling stock
The initial rolling stock for passenger use was authorised prior to the Channel Tunnel opening in 1994. This was prior to the development of European Technical Specifications for Interoperability (TSIs) that could have been used as effective standards for design of rolling stock.

The safety considerations in case of fire have been based on certain scenarios relating to the occurrence of fire. A train could, with a fire on board or when affected by another, similar incident, run through to the emergency sidings at the end of the tunnel, or there could be a controlled halt with evacuation of occupants into the service tunnel through the nearest cross passage.

In some circumstances the train halt may have to be ‘uncontrolled’, perhaps necessitating a greater distance to the cross passage and the safety refuge of the service tunnel.

The preference from 1994 was for a train with a fire on board to travel through to the emergency siding, if it were possible. This procedure was on the basis of a train running capability of 30 minutes.

During the train’s travel to the siding, passengers would move along the train to an unaffected part, and the fire isolated. If, however, evacuation were necessary, passengers would pass directly from the train into the service tunnel. If the train is damaged, or malfunctions, prevent further ravel, it can be split and the undamaged part driven out.

In accordance with these planned procedures, the specific safety rules introduced in 1994 stated that passenger trains were to have a 30-minute running capability at least.

The 400m-long passenger trains have a continuous through corridor to facilitate direct evacuation to the service tunnel. The construction of the carriages – and so the corridor – are smoke tight to prevent breathing difficulties in passengers until the short crossing to the cross-passage and safe haven.

The train has to have a traction system suitable for the tunnels, and be fitted with fire detection and suppression systems in the locomotives. In accordance with recovery procedures, the train would also need to be ‘splittable’.

Rules revision
Following consultations with all interested parties in 2010 it has been proposed that the above rules be revised. This is in accordance with European Directive 2004/09 that requires safety standards be maintained or improved.

Some of the main provisions are as follows. The need for a 30-minutes running capability is maintained. Formations of train construction, other than the 400m-long standard train with corridor, will be allowed if a safe evacuation procedure can be demonstrated. The carriages and connecting corridor would still have to be smoke-tight, although a choice of technical solutions to achieve this will be allowed.

The principle of distributed power is accepted, but fire detection and suppression systems will be required in each motor unit. The train ‘splittability’ requirement has been abandoned.

Overall outcome
The updated requirements for passenger rolling stock to pass through the tunnel will enable new passenger trains to be authorised, but meanwhile retaining safety standards. This will also facilitate new Channel Tunnel train services.


Freight shuttle train entering a portal Major fire damage to the concrete lining of the running tunnel with spalling from and behind the steel reinforcement View through a freight shuttle club-car window to a cross passage – the escape route