Specifying Non-White Light Sources in Outdoor Applications to Reduce Light Pollution

ABSTRACT

Anthropogenic (“human-generated”) light at night (ALAN) from outdoor lighting produces light pollution and as a result causes a range of deleterious responses in humans, plants, and animals. An emerging strategy to combat light pollution, especially sky glow, is to use “amber” LEDs in lieu of phosphor-converted white LEDs with high correlated color temperatures. Importantly, however, there is no standardized terminology or chromaticity designation that is applicable to “amber” LED lighting products for outdoor illumination. In this work, we propose a specification structure for light sources with nonstandard chromaticities to increase the precision of language used in the architectural lighting industry and demonstrate that light sources with well-defined chromaticity ranges outside of the ANSI C78.377–2017 quadrangles may be useful for reducing the portion of relative sky glow related to light source spectral power distribution. We encourage lighting standards development organizations to consider standardizing such a system.

KEYWORDS:

• Amber
• anthropogenic light at night (ALAN)
• artificial light at night
• light pollution
• light emitting diodes
• architectural lighting
• sky glow

Acknowledgments

We want to gratefully acknowledge the professionals who took the time to share with us their knowledge, experience, and perspectives. Their input was indispensable.

Disclosure statement

TE was compensated by Efficiency Forward for work on this project. LR is an employee of DesignLights Consortium. The DesignLights Consortium is a non-profit organization that relies on revenue from its programs to fund its operations. DLC reserves the right to implement programs derived from its research, including this research.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15502724.2022.2121285

Additional information

Funding

This work was funded by Efficiency Forward, Inc., parent company to the DesignLights Consortium.