From midday on Friday, average safetycCameras will be operational along the N5 in Swinford, Co Mayo, and the N3, Co Cavan.
Those found exceeding the designated speed limit will face fixed charge penalty notice, a fine of €160, and three penalty points.
The cameras on the N5 are located between Lislackagh and Cuilmore in Swinford. On the N3, they have been installed between Kilduff and Billis in Co Cavan. They operate in both directions.
Speed is a significant contributor to road deaths and a cause in 30 per cent of fatal collisions, gardaí said.
Average safety cameras work by monitoring a vehicle's speed over the distance of the safety camera zone, rather than at a single point. The speed is not recorded by the cameras at the entry and exit of the safety camera zone.
They are intended to change driver behaviour, reduce the average speed of road users and the number of collisions that occur, making roads safer for all road users and decreasing the impact of speed on local communities.
International studies have found that speed cameras can influence a reduction in collisions and the severity of collisions through the ‘halo effect’ – where drivers have been found to reduce speed due to the presence of speed or safety cameras.
Commissioning, testing, and validation of the cameras got underway earlier this month.
From midday on Friday, vehicles detected driving in excess of the 100km/h posted speed limit will be subject to prosecution.
Surveys carried out before work began and after civil works were completed for the new cameras on the N5 and N3 have already demonstrated the halo effect, with significant increases in driver compliance.
A further average safety camera zone will be completed by the end of 2024 and become operational in Q1 2025.
Six static safety cameras will be operational before the end of 2024 and a further three static safety cameras in Q1 2025.
These three average safety camera zones and nine static safety cameras are funded directly from An Garda Síochána budget.
Speaking at Garda Headquarters, Commissioner Drew Harris said: "An Garda Síochána remains committed to road safety and average safety cameras have been shown to reduce speed and impact positively on driver behaviour.
"The addition of two new average safety camera locations along the N5 and N3 will add to the suite of measures already being undertaken by An Garda Síochána in the area of improving road safety.
"I’m pleased to say that we will have a further six static safety cameras live by the end of this year, with a further three static cameras coming on stream in the first quarter of 2025.”
Assistant Commissioner for Roads Policing, Paula Hilman, said: "These camera sites have been chosen because they have been identified as high collision sites, with numerous road traffic collisions involving injury, serious injury and fatalities occurring along these routes.
"Research has shown that the presence of average safety cameras has the effect of increasing compliance with speed limits, and this then ultimately has a positive impact on road safety in such locations.”
