Operators of GoSafe speed vans are to stop work again over the October Bank Holiday weekend in a dispute over working conditions and union recognition.
The employees will strike for 72 hours beginning at 9am on 26 October.
The workers, who are members of the union SIPTU, have also begun additional industrial action today.
The escalation follows a one-day work stoppage on 28 September.
"Our members have been left with no option other than to escalate this dispute with a 72-hour work stoppage and by implementing industrial action in the form of refusing to operate the Telogis tracking system which monitors their work activity," said SIPTU Organiser Brendan Carr.
"Our members are only taking this action as a last resort because of the intransigence of management which has refused to address their concerns relating to health and safety and their conditions of employment."
SIPTU claims its members can be confined to their van for up to 11 hours while conducting their duties.
It says the shifts are so long that staff are using plastic bottles for toilet breaks.
GoSafe, a consortium based in Listowel in Co Kerry, operates the roadside speed camera vans under a State contract.
SIPTU claims the workers have tried to resolve the issues through the State industrial relations machinery.