LEADERS of electrical union Amicus are expected to start balloting for industrial action today (Thursday) at Heathrow's T5.
The move follows a final meeting in the disputes procedure at Britain's biggest building site yesterday following a longrunning row over travelling allowances on the job.
Around 500 sparks, employed mainly by Amec, Crown House and Balfour Kilpatrick, are demanding an extra £25 a day payment to compensate them for travelling delays to and from work at the congested site.
But client BAA and the employers are standing firm and refusing to up the electricians'money.
The M&E operatives are upset because building and civil engineering workers employed by Laing O'Rourke at T5 receive a £25-a-day travelling allowance under a separate deal.
Amicus national officer Paul Corby said: 'If the Wednesday meeting fails to reach a solution and I receive a request for an industrial action ballot, I will have no reservations in signing that.
'When Laing O'Rourke workers get out of their cars and on to the site buses they get a £25 payment.
'When our people get out of their cars and onto the same buses they don't, which is a recipe for disaster.
'It is horrendous getting to and around that site and our members are simply asking for the same remuneration as BAA has agreed for the building and civils people.'
M&E work at the site is covered by the Major Projects Agreement, which is designed to provide higher wages in return for increased productivity and better industrial relations.
The MPA has been in existence for more than a year but has only been adopted at T5.
Mr Corby said: 'I am a believer in the MPA but the employers haven't got the confidence to adopt it.They are going to clients now with two prices - one using the MPA and the other just carrying on as normal.
'A lot of employers would rather carry on using agencies and condone tax fraud.
They are just sitting back and seeing how the MPA is working at T5 and a lot of clients are being put off.'
BAA said it would release a statement after yesterday's meeting.