In the U.S. alone, there are about 16.2 million public and commercial outdoor light fixtures including streetlights, parking lot lights, and lighting on commercial buildings.
Although residential outdoor lighting isn’t as bright as that of public and commercial outdoor light fixtures, there’s certainly a lot more of it – about 1 billion light fixtures in all!
So, how do you evaluate your current or proposed lighting at your home or business? Asking the following questions while inspecting your outdoor lighting is a great place to start. (For a good overview on lighting, see our Lighting Basics webpage.)
- Does the area really need to be lit?
- If so, for what purpose?
- At what brightness?
- Do any of the fixtures emit light above 90 degrees?
- Is light trespass (light falling where it is not intended, wanted, or needed) an issue?
- Is glare (excessive brightness that causes visual discomfort or difficulty seeing) an issue?
Depending on your answers, the following recommendations may apply:
- Don’t light an area if it’s not needed.
- Turn off the lights when not in use.
- To save energy, don’t use excessive amounts of illumination.
- Use timers, dimmers and motions sensors whenever possible.
- Use only “full cut-off” or “fully shielded” lighting fixtures. That means no light above the 90-degree angle. Fully shielded lighting can be purchased or retrofitted. See below.
- Use energy-efficient lighting sources and fixtures.
- Only use lighting sources with correlated color temperature (CCT) no higher than of 3000K. [link to FSA Standards PR] Most lighting products provide this information on their package labeling.
All of these recommendations should improve the quality of your outdoor lighting by minimizing glare, light trespass, skyglow and energy waste, while improving the efficiency and ambiance of your outdoor lighting.
Finding Dark Sky Friendly Lighting
IDA maintains a searchable database of lighting products certified by our Fixture Seal of Approval program to reduce glare, light trespass and skyglow. Search our database or look for IDA Fixture Seal of Approval on outdoor lighting at your local retailer.