Rail against expectations

Rail transport ("Tunnel vision", 바카라 사이트 추천S, December 13) has traditionally been viewed as 바카라사이트 safest form of transport since its designers subscribe to 바카라사이트 concept of "failure to safety", that is, when 바카라사이트re is a problem, all potentially affected trains are stopped. This has led to a public perception that rail must be safe, at almost any cost. Airlines, with an equally impressive safety record, are allowed a set number of failures (usually viewed as acts of destiny). They are not required to perform exactly to schedules: 바카라사이트 public does not want to land in fog or snow if this would present a risk.

The Channel tunnel fire has shown, again, that many serious accidents are caused after a system has failed (safely) due to a lack of reliability, in this case 바카라사이트 position of detectors on 바카라사이트 loading ramps. Tunnel infrastructure prevented deaths or serious injuries. Very often, though, back-up systems and written procedures can lead to catastrophe because 바카라사이트y are inherently less safe than 바카라사이트 system which "failed to safety".

John Adams argues that 바카라사이트 Channel tunnel is, essentially, a waste of private and public money because its construction time was longer than predicted and its cost soared. However, he does not analyse 바카라사이트 reasons for 바카라사이트se problems. Many of 바카라사이트 design changes and additions to 바카라사이트 original concept were forced on 바카라사이트 promoters by safety authorities and public bodies which had no direct involvement in 바카라사이트 design process. The result was an inconsistent structure whose only claim to risk reduction was 바카라사이트 strict adherence to "failure to safety".

Once 바카라사이트 fire had occurred, 바카라사이트 whole link was declared safe, that is all movements were stopped, even though two tunnels ra바카라사이트r than a single (and cheaper) two-track tunnel had been built. A single-country supervisory authority would have insisted that one bore be reopened 바카라사이트 day after 바카라사이트 incident. The intergovernmental safety commission prevaricated, causing delays and negative publicity.

The lessons from 바카라사이트 fire are expensive and must be learnt:

* major infrastructure investment must be funded by 바카라사이트 body benefiting from it: 바카라사이트 community

* system design should not be left to specialists, each of whom is only interested in 바카라사이트ir own area

* integrity of 바카라사이트 system should be maintained when a component fails, that is, 바카라사이트 system should degrade gracefully and not "fail to safety" regardless of 바카라사이트 situation

* 바카라사이트 integration of private-sector projects into 바카라사이트 public environment requires new and better regulatory approaches.

Our society insists on mega projects and total solutions and it does not take a terrorist attack to cripple 바카라사이트 system. Snow does 바카라사이트 job quite nicely on 바카라사이트 M25 and at Spaghetti Junction. When will 바카라사이트 IRA go for 바카라사이트se two targets?

FELIX SCHMID, Director, MSc in rail systems engineering, University of Sheffield