Question to the Department for Transport:

To ask the Secretary of State for Transport, what assessment his Department has made of the effect on people with epilepsy of flashing lights on pedal cycles.

Published research identifies that flashing lights at certain intensities have the potential to trigger seizures in those who suffer from photosensitive epilepsy. It also reports the likelihood of such effects to be low and the frequency range most likely to cause such a response is 5-30 flashes per second (5-30Hz).

As such, the Road Vehicles Lighting Regulations 1989 (as amended) permit flashing bicycle lamps only if they have a frequency of no greater than 4 Hz, and not so bright as to cause undue dazzle or discomfort to other road users.