Too often, outdoor electric lighting installations at night are over lit, left on when not needed, and are harmful to the environment. As a result, light pollution is a growing global issue that can negatively affect our environment and impact our quality of life. IDA and the Illuminating Engineering Society have published the joint Five Principles for Responsible Outdoor Lighting. By joining forces, our shared goal is to prevent and reduce light pollution through the proper application of quality outdoor electric lighting.
By applying these principles, properly designed electric lighting at night can be beautiful, healthy, and functional. Projects that incorporate these principles will save energy and money, reduce light pollution, and minimize wildlife disruption.
Five Principles for Responsible Outdoor Lighting:
If light is deemed useful and necessary, follow these guidelines to prevent, or when that’s not possible, minimize light pollution.
USEFUL – All light should have a clear purpose.
Before installing or replacing a light, determine if light is needed. Consider how the use of light will impact the area, including wildlife and the environment. Consider using reflective paints or self–luminous markers for signs, curbs, and steps to reduce the need for permanently installed outdoor lighting.
TARGETED – Light should be directed only to where needed.
Use shielding and careful aiming to target the direction of the light beam so that it points downward and does not spill beyond where it is needed.
LOW LIGHT LEVELS – Light should be no brighter than necessary.
Use the lowest light level required. Be mindful of surface conditions as some surfaces may reflect more light into the night sky than intended.
CONTROLLED – Light should be used only when it is useful.
Use controls such as timers or motion detectors to ensure that light is available when it is needed, dimmed when possible, and turned off when not needed.
COLOR – Use warmer color lights where possible.
Limit the amount of shorter wavelength (blue–violet) light to the least amount needed. Light where you need it, when you need it, in the amount needed, and no more.
To gain a fuller understanding of IDA’s approach to lighting, click here.
Read the original April 2020 Lighting Principles announcement (includes a Spanish language version).