The power of a car engine is measured by horsepower
- the more the better. The same can be said for reflective
material, which is measured by candle power (cd/lux/m²).
There is a clear relationship between retroreflective
performance of a surface and the distance at which it
can be seen. According to 3M data, the retroreflective
performance level (candle power) of white clothing is
0.1 - 0.3 , a license plate's performance level is at
50 and typical retroreflective silver fabric has a performance
level of 500.
As the following chart depicts, with increasing retroreflective
performance, sight distance also increases, clearly
demonstrating that reflective materials allow for optimal
visibility during low light level conditions. However,
not all reflective materials are the same, as there
are reflective materials available that range from 65-600