The strike will begin on Saturday.
SIPTU members who are employed by the state as speed camera van operators will begin a 24-hour work stoppage at 6am on Saturday (28 September).
The decision was taken in order to draw attention to the working conditions of those operating the vans, who sometimes spend as much as 11 hours without leaving the van.
SIPTU organiser Brendan Carr said: "Our members have been left with no option other than to conduct this work stoppage. They are aware of the implications this will have on the vital role they play in road safety and have called on motorists to respect speed limits during their action."
According to Carr: "Our members are only taking this action as a last resort because of the intransigence of management who have refused to address their concerns relating to health and safety and their conditions of employment. These workers have attempted to address these problems through the State industrial relations mechanisms.
"However, the company has refused to engage with the workers through their union despite the service they provide being fully funded by the State."
The company in question is Road Safety Operations Ireland, who operate Ireland's network of speed camera vans.
Carr further said that SIPTU have written to Minister for Justice Charlie Flanagan to intervene in order to offset the need for a strike, but that the minister has declined to do so.
