There have been angry scenes at the picket lines between contractors being bussed into Green Isle to take over TEEU members' work and picketers amid claims of race-based propaganda.
The Irish Congress of Trade Unions last week granted an all-out p
icket on the plant, which was placed last Thursday.
Some 35 TEEU (Technical, Engineering and Electrical Union) workers at the plant are into their fourth week on strike.
Green Isle is calling the all-out action illegal. It says that there are SIPTU workers in the plant who have not been balloted on industrial action, which makes the all-out action invalid.
SIPTU refuses to confirm or deny that members of the Green Isle plant belong to its union.
The contract workers, who were brought in about five weeks ago, are being housed in a luxury hotel on the outskirts of Naas and are brought in for their shifts by a local bus company.
Over 30 contract workers have been brought in by Green Isle to cover the work of the TEEU fitters and electricians on a shift basis at the plant.
These contract workers are staying at Killashee House Hotel. Green Isle refuses to comment on the cost of the workers' lodgings, apart from saying it is "at a par".
According to Paddy Hughes, spokesperson for Green Isle Foods: "Picketing workers were asked to remove racist signage along the lines of 'Tiocfaidh Ar La!' and 'British Scab Bastards'. Those signs were removed by the picketers. For that reason and that reason alone, a HR official was present on the bus for the first day or so."
TEEU shop steward at the Green Isle plant Declan Shannon denied the company's claims about the posters. He said there was no 'Tiocfaidh Ar La!' poster and none using 'Bastard'. He said that the picketers had removed one poster saying 'British Scabs Out' after the company's objections.
There are now 27 TEEU members actively picketing the Green Isle plant on a shift basis. Some picketing workers at the Green Isle plant claim that some of the contract workers on the bus have been making gestures and pulling faces as they pass the picket, which is incensing the picketers.
Eamon Devoy, general secretary designate of the TEEU, called the contract workers "industrial Black and Tans".
Mr Shannon said that the striking workers have received "a great amount of support from the public" since moving their picket line to the entrance of the IDA industrial estate on the Monread Road.
Locals have dropped supplies including pizza, doughnuts and newspapers off to the picketers.
Mr Devoy said that Green Isle has refused to use an independent facilitator to settle the dispute, and called on the company to use the country's industrial relations mechanisms.
However, the company spokesman said that reason behind the strike is, "A cut and dried case of dismissal for people who seriously breached IT policy by accessing and emailing adult material of a serious nature."
The workers claim the row arose when members sent around an email about redundancy proposals.
A fundraiser in aid of the striking TEEU members was held in the Teachers Club in Parnell Square last Friday night. Over n2,000 was raised for the strike fund, and an appeal has gone out to 1,000 of the union's shop stewards across the country to hold collections for the Naas workers.
Green Isle Foods says there is no disruption at the site and production is continuing as normal.
