DUBLIN City Council has dismissed fears that flashing lights from its trucks might cause epileptic fits.
The local authority has pointed to research showing the rate at which the warning lights flash is too slow to cause seizures.
Unease had been expressed to the council that the beacons could be a danger for those who are photosensitive.
In a report to its environment committee, the council said: "The concern about the health effects of these flashing beacons seems to centre on the fear of these beacons inducing epileptic seizures in people."
It added: "A fact sheet published by Epilepsy Research UK details a list of triggers for the very small percentage (5pc) of epilepsy sufferers who are photosensitive and includes lights flashing at a rate of 5-30 flashes per second."
The council said the flashing beacons on its vehicles "flash approximately twice a second, slower than the trigger rate".
"They are mounted at a height of 2.4 to 3 metres which means they take up a small area of a person's field of vision," it added.
The council also highlighted the importance of having the warning lights.
It said investigations show that nearly 5pc of severe truck accidents are caused by the truck not being readily visible.
"The flashing beacons on vehicles help alert road users to the fact that there is not only a slow-moving vehicle ahead but also that there are council employees in the vicinity.
"They are an essential part of the safety system protecting employees and members of the public," the report stated.
However, a contributor to the Epilepsy Action website in the UK, whose son suffers from "marked photosensitivity", stated that the boy had a seizure caused by the flashing lights of a truck.
The contributor wrote: "Our bathroom window faces our road and has a frosted pane of glass with leaf patterns on it.
"A lorry with yellow flashing lights pulled into our road and was stationary outside our house.
"The lights magnified in each of the leaf patterns, making it look like a mass of flashing images. Unfortunately, my son was in the bath at the time and ended up having a seizure."