Gardai will conduct a national Slow Down Day on Friday, with motorists advised to adjust their speed to all prevailing road, traffic and weather conditions.
The 24-hour road safety speed initiative gets underway at 7am Friday morning, and the objective is to reduce the number of speed-related collision, save lives and reduce injuries on Ireland's roads.
Excessive speed is a major factor in one-third of fatal road collisions, and Gardai say a 1% reduction in average speed will bring about a 4% reduction in fatal collisions.
Recently, Gardai detected a driver on the N61 in Roscommon travelling at 143 km/h in a 100 km zone, while a motorist on the M6 in Galway was driving at 155 km/h on a 120 km zone.
The Road Safety Authority is also urging drivers to slow down - especially when the weather deteriorates and roads are more likely to be wet, which means increased stopping distances.