Q&A: Transport safety expert

Thirteen people died and 70 were injured in the crash

Andrew Evans, Professor at University College London in Transport Safety, answers BBC News Online questions on rail and road safety as the grim task of sifting the Selby rail crash wreckage continues.

News Online: Could rail speed restrictions, which were lifted last week, have helped to lessen the impact of this crash?

Prof Evans: Conceivably, if the trains had been going much more slowly the consequences would have been less severe. I don't think they would have prevented the accident because there was so little time between when the car landed on the tracks and the passenger train came along and then the freight train. I don't think that even if they had have been going more slowly the collision could have been avoided.

News Online: Would seat belts or some similar device have helped to lessen the impact of this crash?

Prof Evans:

Road safety measures are generally relatively low cost compared with rail safety measures

Prof Evans

Conceivably. It is not only people being thrown around the carriage that is the problem, but other objects in the train hitting people. But I think seat belts would only remotely be a possibility for InterCity trains that do not stop very often and generally do not have standing passengers. They certainly would not work for commuter services and I think it is unlikely that it would have made a difference to the death toll on this occasion - the coaches were so severely crushed.

News Online: We keep saying that nothing could have been done to prevent this accident, but are the motorway crash barriers one area where there is room for improvement?

Prof Evans: Well, we don't know, but I think that is the only thing that would have made a difference. I understand that the barriers in this case weren't in any way deficient. Obviously, someone has decided that that is an appropriate length and I have no doubt that the length will be reconsidered. A lot of work has been done on crash barriers generally for motorways but what you have got to do is design them so they can absorb enough energy to slow the vehicle down but prevent it from bouncing back onto the motorway, which would be equally dangerous.

News Online: Do you have any idea how much such an operation would cost?

Prof Evans: Road safety measures are generally relatively low-cost compared with rail safety measures. We have got to the situation where rail safety measures tend to be rather expensive. I think it is worth doing at least a "back of envelope" type of calculation, which I haven't done, to see how much it would cost.

News Online: In France they have a system of trip wires, so that if a vehicle falls off a bridge trains are automatically brought to a halt. Could we not implement such a system here?

Prof Evans: Yes, that system means that if anything gets near the overhead wire a switch gets thrown and the electric current is cut off. That would only work where you have got electric traction - the GNER passenger train was an electric train - the freight train wasn't - so it would not have automatically stopped the freight train.

The problem in this situation was that the train was far too near to stop whatever the signal said.

Prof Evans

What one has to remember is that even if the driver of the road vehicle had successfully made his 999 call, there would have then been some delay in which the information that there was a car on the track would have been transferred to the railway system and the railway signals changed. If there was some automatic device to ensure that happened straight away, it might be useful.

I should say that if the road vehicle had straddled the two rails on which the train runs and had electrically connected them then that would have been interpreted by the signalling system as a train so the system would have thought that there was a train already there and it would have put the signals to danger.

I don't think one should seriously think about not travelling by train for safety reasons and I don't think people do

Prof Evans

The problem in this situation was that the train was far too near to stop whatever the signal said.

News Online: This is the fourth fatal crash in three and half years on the network - just how safe are our railways?

Prof Evans: They are not perfectly safe regrettably. But although it is these kinds of accidents that get all the attention, it is still the case that the number of people who are killed on the railways in train accidents is a small proportion of all the people that are killed on the railways in total. Most of the people who die on the railways die in unreported accidents - like people falling off platforms or track workers being struck by trains and there aren't that many of them but there are lot more than in these high-profile accidents and, of course, there are lot fewer on the railways than on the roads.

The frequency, on my analysis, with which we have been having train accidents, although it is much higher than one would want, is still low compared with the past. It is roughly one a year or slightly more at the moment and that compares with four or five times that number 30 years ago.

I don't think one should seriously think about not travelling by train for safety reasons and I don't think people do. The main reason why people stopped travelling in large numbers after the Hatfield accident was not because they were afraid of the risk but because the train service became so bad.