Advancing responsible outdoor lighting
DarkSky advances responsible outdoor lighting through policy positions, public education, scientific research, partnerships, and more.
Our desire to light our world at night is not new. We have illuminated our outdoor public places and private realms for centuries. What has changed is that outdoor lighting is now ubiquitous, cheap, and powerful. With it, the world has gotten brighter. A lot brighter.
Lighting brings tremendous benefits to modern society. It has revolutionized the way we live and work outdoors. Modern society requires outdoor light at night for various needs, including safety and commerce.
Responsible outdoor lighting
- Meets the needs of people to see at night
- Conserves energy
- Avoids harmful effects on wildlife
- Protects our night sky
The Five Principles for Outdoor Lighting
We promote a holistic approach to light pollution reduction using the Five Principles for Responsible Outdoor Lighting.
Thoughtful lighting installations limit light to where it is needed, and only in the amounts necessary. This approach eliminates unnecessary lighting and light going up into the sky, and reduces over-lighting, glare, and lighting that spills out past its intended area.
Responsible outdoor lighting is
1 — Useful
Use light only if it is needed
All light should have a clear purpose. Consider how the use of light will impact the area, including wildlife and their habitats.
2 — Targeted
Direct light so it falls only where it is 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.
3 — Low level
The 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.
4 — Controlled
Use light only when it is needed
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.
5 — Warm-colored
Use warmer-color lights where possible
Limit the amount of shorter wavelength (blue-violet) light to the least amount needed.
Lighting policy and ordinance database
In partnership with the University of Arizona’s James E. Rogers College of Law, we are developing a database of case law and statutory law about lighting issues. The database will be available later this year.
In the meantime, you can review our 2018 report on US case law.
Global standards and partnerships
DarkSky participates as a stakeholder in many of the professional organizations that establish lighting standards worldwide, including the International Commission on Illumination (CIE) and the Illuminating Engineering Society (IES).
Our advocacy is focused on getting light pollution recognized as a core issue and incorporating the Five Principles for Responsible Outdoor Lighting in all relevant standards.