Bicycle lights are important to see and be seen. Lights are important to light your way, make hazards visible, and be seen by other people utilizing paths and roadways. You should use them during the day, inclement weather and in the evening. To ensure that you are visible most bicycling guides recommend that lights be no less than 200 lumens, but 400 to 1000 lumens is preferred.
According to Louisiana law it is required that people on bicycles have both a rear red light and a front white light that are visible from 500 feet away.
Settings: to blink or not to blink
Some recommend in urban environments a person on a bicycle should use the light flashing setting to be more visible against the multitude of already existing lights. In rural settings, it is more recommended to have a solid light to be more visible to people driving by having a continually visible light against the darker environment. For most purposes, blinking lights attract more attention and will alert others of your presence.
Reflectors are an additional way to be more visible, but they will not help you see. Reflectors require an external light source such as vehicle headlights to be work and make you visible. Reflectors are often attached on bicycle wheels, seat posts, pedals, and handlebars. Reflectors can also be added to bicycle helmets, sewn into clothing, worn on vests and ankles.
There is no limit to the amount of bicycle lights and reflectors one can adorn their bikes and themselves with. There are endless possibilities, so be creative and make yourself visible. The more lights and reflectors the better. There is safety in numbers!