BRITAIN’s rail operators face the prospect of substantial capital investment for unquantified safety benefits. On May 21 the Health & Safety Executive issued for consultation Draft Railway Safety Regulations which would require widespread installation of the Train Protection & Warning System (RG 1.98 p55) and withdrawal or modification of MkI slam-door rolling stock.
Health & Safety Commission Chairman Frank Davies said that while railways were the safest mode of land travel in Britain, ’improvements in technology mean they can be made safer. We believe the only way that progress to a reasonable timescale can be assured is to make new regulations ... the HSC is confident that these proposals represent an important step forward in railway safety. The public expects and deserves no less’.
The new regulations would require the installation of TPWS by January 1 2004 at all locations where signals control potentially conflicting movements, at major speed restrictions and at station buffer stops. All loco and train cabs would also have to be equipped by the same date. TPWS is designed as an enhancement to the standard BR automatic warning system which would be cheaper than full automatic train protection; intended to function both as a speed trap and a train stop, it is still under development.
HSE estimates the cost of fitting TPWS across the network at £100m. However, Railtrack had priced at £150m the fitting of 25% of signals, which Director, Safety & Standards, Rod Muttram says would provide over 96% of the safety benefits of network-wide installation. As Railtrack’s aim is to fit transmission-based train control on much of the network, wider installation of TPWS may not be the most effective use of resources.
In the case of MkI stock, vehicles will have to be withdrawn by January 1 2003 unless their underframes are modified to incorporate a cup-and-cone over-ride prevention device, and slam doors are fitted with centrally-controlled secondary locking. The price tag is put at £30m to £40m.
While TPWS is likely to give safety benefits in the region of Railtrack’s basic Value of Preventing a Fatality of £0·95m, the MkI modifications exceed the ceiling of £2·65m which is applied only where risks at the ’upper limit of tolerability’ are being addressed. HSE Chief Executive Jenny Bacon insisted that ’we are not working to any figure per life saved’.
According to the HSE, continuing use of the current fleet of MkIs would result in one fatality a year which could be attributed to crashworthiness; introduction of TPWS would halve the risk of collisions and derailments. Fatalities caused by falls from slam doors currently average between two and four a year. o
