Cyclists - How dangerous is cycling without good lighting?

Estimates based on registered injury crashes in the period 2002-2010 indicate that bicycle lighting is effective. A regression analysis shows that the risk for cyclists of being involved in a crash during darkness decreases by about 17% with working front and rear light. The researchers, however, find the uncertainty in the outcome too large for a reliable estimate of the size of the effect. Also, the quality of the bike lights has not been taken into account (results therefore relate to such bike lights as were customary in those years [32].

We do know, however, that the risk of a crash is greater for cycling in the dark than for cycling during daylight [3] [33]. If one corrects for the distance travelled, then it turns out that the risk of being a seriously injured in a  bicycle crash is highest in the dark during the early hours of the morning (after midnight and until the morning dusk). In addition to poorer visibility, alcohol use also adds to the greater risk of cycling in the dark.

See also the archived SWOV Fact sheet What are the risks of cycling during darkness?

In the winter of 2012/2013, an average of 61% of the cyclists used  front and rear lights during the morning rush hour and in the early evening [34]. In the summer of 2015, the average was 41% in entertainment areas and during nightlife hours [35]. Because of differences in the study designs (observation times, locations), the results are not comparable. Therefore the differences do not give any indication about possible developments over time.


Fact sheets(s)