Safety of Bicycle Lighting
he use of lights for night riding is generally recommended or required by authorities as a basic safety precaution, even in a well-lit urban context. Studies show a correlation between collisions and failure to use lights even during daytime.
It is generally believed that reflectors alone are inadequate for night riding (almost all cycling organisations unconditionally advocate using a headlight at night), but the Consumer Product Safety Commission and other regulatory agencies have declined to mandate the inclusion of active headlamps with new bicycles, citing increased costs compared to benefits and the fact that most bicycles are not ridden at night.
It has been estimated that 75% of bicycles used in the United States at night do not meet the legal requirements for lighting[citation needed]. This may be because the majority of unlit cyclists are riding in urban areas with many streetlights, and bicycles are not required to be sold with a headlight. In countries where bicycles are used widely for commuting and short trips, such as the Netherlands and Scandinavia, bicycle head- and tail lighting regulation is heavily enforced by the authorities.