A simmering safety row between tube unions and Transport for London has resulted in a third strike ballot.
The leader of the Rail Maritime and Transport union says TfL and London Underground are "dicing with death" with plans to double the length of time between safety train inspections from 14 days to 28 days.
A ballot for industrial action of all tube fleet maintenance staff is being prepared.
A separate ballot 10,000 of its members on whether to walkout over cut backs closes on August 11.
The Transport Salaried Staffs Association is also consulting its 1,000 members over the cuts - their vote closes in a week. Both unions warn that any strikes would start in early September, as schools reopened after the summer holidays.
Unions claim that a cut in the frequency of braking and other equipment is a "blatant cost saving measure" that are "another element of an overall attack on jobs and safety."
Wider conflict
The conflict over axing of 800 ticket staff and 140 offices has allied itself to a wider safety row. In the past few weeks two fires were spotted by staff before safety equipment kicked in. The incidents have galvanised the unions position that less staff means less safety.
One of those alerts occurred during this morning’s rush hourat Oxford Street, the RMT's latest strike threat was announced moments later.
In the other incident, TfL maintain there was no escalator fire at Euston and that if the staff member had not spotted the smoke, alarms would have sounded two minutes later - the RMT have reffered the incident to rail regulators.
"TfL playing fast and loose with safety"
RMT General Secretary Bob Crow said "hardly a day goes by now without TfL and LU getting caught out playing fast and loose with staff and passenger safety".
Adding:
These fortnightly inspections identify worn brake blocks, cracks in securing brackets and other distressed components.
RMT has a stark choice – ballot for action or sit back and wait for a disaster to unfold. We have chosen to ballot for action".
Industry insiders are convinced that the union is determined to press ahead with the network wide strike, a broadside to the coalition government seeks to cut costs.
Transport for London have in turn attacked what they call the "scare tactics" of the union and stressed that the changes to staffing and ticketing will have a minimal impact. LU's Howard Collins said:
"What we are seeking to do is deploy staff more visibly in stations where they can more easily assist passengers.
