A total of 31 people died in the Ladbroke Grove crash
Some train drivers are putting lives at risk by over-riding a new warning system designed to prevent trains passing red signals, according to rail safety officials.
There have been several incidents in which drivers have re-set the warning system, failed to tell the signal man and continued in violation of safety rules, according to the Health and Safety Executive.
The new Train Protection and Warning System (TPWS) is now being fitted across the network designed to prevent disasters caused by drivers passing a red signal.
The system automatically applies the brakes and the train slows down.
Rail companies are now considering new measures to stop drivers breaking the rules.
The system has already intervened more than 100 times in the last year.
The Ladbroke Grove and Southall rail accidents happened after trains went through red lights.
A joint inquiry was set up following the two crashes which left a total of 38 people dead.
In March 2001 the Cullen Report recommended that an advanced automatic system to stop high speed trains going past red signals must be implemented by 2008.
Lord Cullen and Professor John Uff proposed the expensive European Train Control System (ETCS) be introduced on high speed lines.
The report recommended that in the meantime, the industry should continue to install the TPWS.