Workers at haulage company Eddie Stobart have placed an official picket at a Dublin depot used by the firm.
A 24-hour work stoppage started at 8am this morning at the firm’s Ballymun depot.
Today is the second day of industrial action at the British-based distributor in recent weeks.
It stems from a dispute over working conditions at the company which is involved in the delivery of goods to Tesco stores across Ireland.
Siptu sector organiser Karan O’Loughlin was critical of the company's response to the workers, saying they were left with "no alternative" but to engage in industrial action.
"This inaction on the company’s part is leaving the drivers with no alternative but to engage in a second industrial action in order to highlight their grievances," she said.
"The refusal of the company to engage has strengthened the determination of the drivers to achieve a fair and just outcome to the dispute."
A statement issued by the company this morning said the majority of drivers do not support the industrial action, and assured customers “that all commitments will be met in full”.
It added: "The ongoing direct engagement between the company, driver representatives and Siptu’s own local representative continues to work positively and we remain committed to this approach.
"Siptu’s claims about our safety standards are misleading and not supported by the facts. Two recent standard audits of our business by the Road Safety Authority found us to be fully compliant. We would welcome inspections by any regulatory body of our safety standards."
However, Socialist Party TD Clare Daly said: “The key issue over which the dispute is taking place is the absence of regular rostering for the workers, whereby they are only informed on a day-by-day basis [about] the precise times of the shifts they work.
"This makes it impossible for them to make any plans in their private and family lives. There are also real health and safety concerns on the part of the workers given the erratic shifts they end up being asked to work," she said.
