Tunnel Safety

DTR is best known for its software, but it is also proud of its contributions to operational tunnel safety.  Alan Vardy first published on this topic over 25 years ago, at a time when most engineers involved in tunnel ventilation paid much more attention to conditions in routine operation than to the response to incidents.  He received special encouragement from John Lowndes at Mott MacDonald Ltd and this led to a four-year, part-time Industrial Fellowship in Mott MacDonald’s offices in Croydon, London.  John had long experience in tunnel ventilation and was passionate about the need to ensure that the emergency services had a proper understanding of its capabilities.

During the fellowship, Vardy initiated a series of international conferences on Safety in Road and Rail Tunnels.  Today, such events are commonplace, but that was not the case twenty years ago. The conferences were co-sponsored by ITC Ltd and the University of Dundee.  Nominally, ITC was responsible for all administrative arrangements and the University was responsible for technical matters.  In practice, however, ITC’s managing Director, Judy Whitham, assisted greatly in building and fostering a community of influential persons with strong motivation for promoting safety based on common-sense design and operation rather than on rule-book instructions.  The latter have their place, but they cannot be the fundamental basis of practical readiness for coping with the huge uncertainties that exist in many incidents. This approach was strongly supported by a Technical Committee comprising leaders in tunnel design, operation and regulation.

Although Vardy’s interest in safety was triggered by concern about prevailing attitudes in the world of tunnel ventilation, the safety conferences were designed from the outset to promote awareness of all aspects of operational tunnel safety.  Topics such as risk analysis, human behaviour, communication, control, insurance and regulation were given greater priority than, say, numerical models of ventilation and even fire development.  In fact, Vardy and Whitham were so disappointed by the failure of one part of the community to participate fully that they set up a second series of conferences on Tunnel Control and Communication. This had the desired effect of eliminating the gap in the Safety conferences.

Control - or is it?	Moral dilemma - rapid decision required

Alan Vardy chaired the Technical Committees of all five Safety conferences as well as both of the Control & Communication conferences.  He received wonderful support and friendship from the committee members, both directly and behind the scenes and would like to acknowledge the huge contribution made by them and by their organisations.  He is especially grateful to Judy Whitham for allowing him to devote unusually large proportions of the conferences to novel Discussion Forums, Debate Forums. Even today, many conferences devote remarkably little time to open discussion even though delegates commonly stress how important it is to them.

Only a few months after the second Safety conference, tunnel safety was projected into the political world by a series of fires in European road tunnels, including the Mont Blanc Tunnel.  These led to significant loss of life and to a wider appreciation of the need for coordinated design of tunnel systems to optimise their effectiveness in response to incidents as well as in routine operation. Similar lessons were learned in the railway world through fires in an underground railway in Baku and a ski-tunnel in Kaprun (Kitzsteinhorn). Nearly 500 people died in these two incidents.  Later, a fire in EuroTunnel caused great public concern even though it involved no loss of life. Commendably, EuroTunnel presented a highly open and informative one-day Seminar at the following Safety conference.  Led by the Director of Safety and the Director of Communication & Control, the seminar showed what can go wrong and what lessons had been learnt.  Human factors figured prominently at all stages, including the aftermath of the incident.

When an incident occurs, it is vital that the tunnel controllers - and, later, the emergency services - should have the information and resources they need to respond effectively. This statement is so obvious that it might be dismissed as trivial by anyone who has not been involved in a real incident. In fact, however, its implications are enormous because it is all but impossible to achieve such a goal. It is almost certain, for instance, that some decisions taken on the spur of the moment by well-intentioned individuals will differ from those preferred subsequently by investigators blessed with the advantages of much more information, much less data and a university degree in hindsight. Tunnels must be designed for real-world situations. Plans must be sufficiently flexible to allow for people - users and operators - making decisions that seem inappropriate with hindsight. The development of such plans requires additional skills on top of those that are needed for the design of anything that is working normally. Conferences that share information about what can go wrong and about what can go right have an important role to play. So do mock incidents in tunnels, especially when as many as possible of the persons responding are not initially aware that the incident has been staged. The following photographs are taken from such an incindent. The "victims" are actors, but the emergency service personnel are not.

Mock incident in a tunnel	Victims	Kiss of life

Selected references

Safety in Road and Rail Tunnels. Ed: Alan Vardy, ITC Ltd & The University of Dundee
(1992)  Basel, Switzerland, 23/25 November 1992 (ISBN: 0-9520083-0-0)
(1995)  Granada, Spain, 3/6 April 1995 (ISBN: 0-9520083-2-7)
(1998)  Nice, France, 9/11 March 1998 (ISBN: 1-901808-03-3)
(2001)  Madrid, Spain, 2/4 April 2001 (ISBN: 1 901808 17 3)
(2003)  Marseille, France, 6/8 October 2003 (ISBN: 1 901808 22 X)

Tunnel Control and Communication. Ed: Alan Vardy, ITC Ltd
(1994)  Basel, Switzerland, 28/30 November 1994 (ISBN: 0-95200831-1-9)
(1997)  Amsterdam, Netherlands, 10/12 March 1997 (ISBN: 0-09520083-7-8)

Vardy,AE (1985) Some aspects of air management in rapid transit systems. Proc 5th int symp on the Aerodynamics & Ventilation of Vehicle Tunnels, Lille, France, 359-370

Vardy,AE (1988) A safe ventilation procedure for single-track tunnels. Proc 6th int symp on the Aerodynamics and Ventilation of Vehicle Tunnels, Durham, UK, 27-29 Sept, 567-574

Grant,GB, Vardy,AE & Davies,PA (1988) Thermally stratified forced ventilation in tunnels. Proc 6th int symp on the Aerodynamics and Ventilation of Vehicle Tunnels, Durham, UK, 27-29 Sept, 527-547

Vardy,AE (1992) Initial emergency ventilation in a twin-track tunnel. Proc 1st int conf on Safety in Road & Rail Tunnels, Basel Switzerland, 127-134

Vardy,AE (1992) Safe operation of vehicle tunnels. SERC Bulletin, 4(10), 12-14

West,A, Vardy,AE, Middleton,B & Lowndes,JFL (1994) Improving the efficacy and control of the Tyne Tunnel ventilation system. Proc 1st int conf on Tunnel Control and Communication, Basel, Switzerland, 28-30 Nov, 473-489

Henson,DA & Vardy,AE (1995) On the time to establish smoke-free egress. Proc 2nd int conf on Safety in Road and Rail Tunnels, Granada, Spain, 3-6 April, 379-386

Vardy,AE (1996) State of the art on safety in rail tunnels. Proc 1st Nat Symp on Fire Safety in Rail and Road Tunnels, Rome Italy, 20-21 June, Italian National Council of Research, Ed: Claudio Podestà & Roberto Arditi, 211-216

Vardy,AE & Wright,K (1998) Emergency procedures and moral dilemmas. Proc 3rd int conf on Safety in Road and Rail Tunnels, Nice, France, 9-11 March, 725-734

Nakahori,I, Mitani,A & Vardy,AE (2010) Automatic control of two-way tunnels with simple longitudinal ventilation. Proc 5th int conf on Tunnel Safety and Ventilation, Graz, Austria, 3-5 May 2010 [in press]