Construction firms named on internet site strongly deny claims that hundreds of electricians were on blacklists.

M&E union Amicus is considering taking legal action against leading M&E firms after it was alleged that several had circulated blacklists containing the names of hundreds of electricians.

The allegations were published in an internet blog by Alan Wainwright, formerly a regional resources manager at a large contractor within the sector.

In it he says the names of electricians have been circulated among leading M&E firms with the intention of ensuring that they were not employed. All these firms, which Building cannot name for legal reasons, have denied the claims.

Wainwright said in his blog: "I have reasonable grounds to believe that certain UK construction companies and their M&E subsidiaries operate a blacklisting procedure to ensure certain electrical operatives do not gain employment on their projects. This is based on procedures I have undertaken in the workplace in previous roles and information that has come to my direct attention."

The alleged blacklists, which Wainwright publishes in his blog, include lists of hundreds of workers who were employed on the Jubilee Line Extension, the Royal Opera House and Pfizer projects prior to the year 2000. All were hit by industrial disputes that were widely condemned within the M&E sector.

Amicus regional officer Frank Westerman said that the union was investigating the matter and seeking legal advice. He said if electricians had been blacklisted, they could be entitled to compensation if they had been unable to find work.

In a separate development a tribunal is due to take place next week involving Emcor Drake & Scull a worker represented by Amicus. The tribunal concerns allegations of blacklisting on the Channel Tunnel Rail Link project.

Emcor told Building that at no time did it operate blacklists.

Westerman said: "We are taking legal advice over the allegations. If any of our members have applied for jobs and feel they have failed because they are blacklisted there might be a chance of legal redress."

The Electrical Contractors Association, the trade body for the electrical sector, said it was not aware of any blacklisting practices.

Director David Pollock said: "The ECA does not condone the use of blacklists. It is not aware of blacklisting being practised within the electrical contracting industry."

Wainwright is taking one of his former employers to tribunal for constructive dismissal, and claims the allegations of blacklisting will surface in the hearing. He declined to comment further.