Abstract
The mandatory use of a red rear reflector and reflecting pedals for bicycles has shown its useful effect on the safety of becycles. A first analysis of the traffic accident data during 1978, the year before the introduction of the mandatory, use, and 1980 shows that in 1980 the number of victims- fatalities and injures taken into a hospital - decreases with 60-80. The efficiency of reflectors increase according as the light condition is worse.