When it comes to outdoor luminaires there are numerous specifications that a designer must take into account when panning the fixture. It is not just about Lumens out. They must take into consideration things such as debris on the heat sink, birds’ nests, feces, and dust not allowing for the same thermal transfer as in the tested conditions. Maintenance can be a challenge for workers who are required to replace, clean, and change components in case of failure. While LED’s are not likely to fail, in some applications the supporting components such as the AC/DC driver can. Vibrations from vehicles and wind can cause discoloration and color shift on LED’s. Outdoor lighting is also subject to power surges at a much higher level than indoor applications based on operating currents. Extreme changes in ambient temperatures and the fact that these luminaires may be used in the far north where it can be extremely cold and in the desert where the daytime temperatures can exceed 110°F can change light output, which can cause the fixture to not meet or exceed the specifications that defined during the design phase.