Regardless, Sparks struck and protested across the country. Pickets were organised at the Balfour Beatty site at Blackfriars, London, and attempts were made to stop lorries entering the site, before a heavy police presence cleared the road. Other action has been seen in Cardiff, Central Library in Manchester, St Catherine's hospital in Merseyside, Glasgow, Kelvin Hall school in Hull and North East Lincolnshire.

Electricians at Balfour Beatty in London have appealed for people to come to Blackfriars station from 5.30pm today, for the arrival of the night shift.

A Hartlepool spark wrote online:

The strikes follow an escalating campaign of action by electricians over the last four months, and could indicate the direction industrial action could take if the government follows through on its threats to make the UK's strike laws - already among Europe's toughest - more restrictive.

The protests began following the announcement in May by Balfour Beatty and another seven of the UK’s 14 major electrical contractors (Crown House, NG Baileys, T. Clarkes, MJN Colston, Gratte Brothers, Shepherds Engineering, Matthew Hall) that they would impose new contracts upon their electricians, and in doing so scrapping the Joint Industry Board (JIB) agreement which has for the past 40 years been the basis for setting pay and working conditions. The firms have drawn up a replacement, the Building and Engineering Services National Agreement (BESNA), and issued notice to employees in August that their current contracts will be terminated on December 7, leaving them with the option of taking up the new contracts or accepting unemployment.

According to Unite, BESNA will have a number of negative effects on the trade. Contractors will be able to continually raise and lower hourly pay according to specific tasks workers undertake at any point in time, rather than maintaining a standard wage for skilled work. For some electricians this will entail a lowering of the hourly rate from £16.25 to £10 – a 35 per cent pay cut.

Unite say that both travel and overtime pay will be cut and made payable only at the employer’s discretion, the ability to claim for unfair dismissal will be reduced, while employers will simultaneously be enabled to make redundancies while agency temp workers are still engaged on projects. As one electrician analysing the agreement put it: “People are going to be losing a lot. Every single term in BESNA gives all the power to the employer. They get final say on everything.”

The JIB agreement has been in place for over 40 years, and part of the reason for its creation was the avoidance of labour unrest. The prospect of its removal is now fuelling some of the most potent labour militancy of recent years.

Protests by rank and file union members have shut down building sites across the country. In September a group of around 1,500 electricians workers at the Lindsey oil refinery in Lincolnshire walked out to join demonstrating electricians and Unite officials, while sites in London have been blockaded and occupied by workers several times in recent weeks.

“We’ve got to have mass walkouts, whether it’s official or not, it’s our very futures at stake,” explained Steve Acheson, Branch secretary for Unite from Manchester.

He said in view of the fast-approaching December deadline, electricians “aren’t prepared to wait for the union to decide what they’re going to do. Time is not permitting. The rank and file are saying we haven’t got enough time and they’re taking action.”

Acheson, himself a victim of Balfour Beatty’s past union blacklisting activity, accused building firms of lacking commitment to negotiations with their workforces.

“They’re just moving the goalposts so they can get the rate down by £3. This is a 43 year agreement they’re walking away from. The root cause of everything is insatiable greed for greater profit.

“The only language these companies seem to understand is industrial action. There’s no dialogue, they don’t want dialogue.”

One of the original eight companies proposing to scrap the JIB, MJN Colston, has already backed down in response to the protests, and the workers are confident that others can be forced into the same decision.

Balfour Beatty, a firm with a recent history of illegal union blacklisting, is viewed as the driving force behind BESNA and as such was targeted by Unite for the first wave of official strike action. While Balfour Beatty have claimed that the scrapping of the JIB is a response to competitive pressures, Unite point out that the companies orders have risen 6 per cent this year, with £15.5bn worth of projects underway since last year, yielding pre-tax profits of £50.5m. Ian Tyler, the company’s chief executive, received a total pay package of £979,994.

Rank and file organisers of the unofficial day of action of electricians across the UK are saying it is the biggest demonstration of its kind in decades.

Estimates of between 300 and 500 sparks walked off one single site at Blackfriars in London, with scores more walking off sites on Merseyside, in North East England, in Scotland and in Wales. They joined a string of demonstrations around the UK on the day when seven rogue employers were due to enforce ‘sign or be sacked’ contracts, de-skilling and undermining safety levels in the industry, and forcing electricians to take a 35% pay cut.

Under pressure from Unite, the companies have now postponed the deadline for introducing the contracts but the union insists the employers must begin serious negotiations or expect actions such as today’s will escalate.

Sparks from the Grangemouth oil refinery invaded and occupied site offices at a fire station being built Balfour Beatty, seen as the ringleader of the employers. Many sparks walked off the job in solidarity.