The British Safety standard BS6102 governs the position and brightness of front and rear bike lights. Not only do certain laws apply in the UK, currently, the EU requires us to recognise equivalent standards from the European Commission. However, the most important guidelines to follow are detailed below - given you apply these you should not encounter any issues. As advised by the Department of Transport, any bike which is used during the hours of darkness or during periods of poor visibility MUST be fitted with the following: a white front light, a red rear light, a red rear reflector, amber/yellow pedal reflectors - front and rear on each pedal. The front and rear lights may be steady or flashing, or a mixture e.g. steady at the front and flashing at the rear. A steady light is recommended at the front when the cycle is used in areas without good street lighting.