A row over maintenance on London Underground broke out today when a union raised safety concerns about the frequency of inspections.
The Rail Maritime and Transport union said there were plans to change the inspection frequency on safety equipment from daily to every 60 days, but Tube bosses said no decision had been made.
RMT general secretary Bob Crow said: "RMT is shocked and appalled that London Underground could even be considering tampering with the frequency of the tripcock failsafe tests. The tripcock is an essential safety mechanism which stops a train in the event of it passing a signal at danger and is known throughout the rail industry as a lifesaver.
"This is a cuts-led move that follows hacking back of safety inspections on escalators and out on the tracks, and comes at a time when maintenance cuts are already causing havoc on a daily basis with signal failures and breakdowns commonplace.
Phil Hufton, LU's asset performance director, said: "No decision has been taken on changes to the frequency of tripcock maintenance on LU trains, but it is absolutely correct that we are working with Bombardier to look at what the right level of maintenance is for the brand new, state-of-the-art trains that are being introduced.
"Just as with modern cars, the technology on board these new trains allows us to download information that will tell us well in advance if any part of the train needs attention, reducing the need to carry out time-consuming and outdated maintenance activities which are no longer the industry norm."