Commercial and Roadway Lighting Tips

Commercial and Roadway Lighting Tips

FDSC strongly recommends amber lighting for most commercial and roadway applications.

The principal purpose for most outdoor lighting is general illumination for way finding and safety – such as in parking areas, roadways, walkways, and even at home. Such lighting (called “Class 2” lighting in some lighting codes) should utilize exclusively fully shielded fixtures to limit glare and off-site spread of the light, and amber sources to minimize sky glow, ecological impact, and potential human health impacts. (The sky glow impacts of spectrum are discussed on our Lamp Spectrum and Light Pollution page.)

For dark skies the data are clear – Amber is best by far.

The lowest-impact source is NBA LED; the second-lowest are high-pressure sodium and PCA LED. Even the lowest-CCT white LED – often suggested as dark-sky friendly by others – have significantly greater impacts than good PCA LED (~2.5x greater), and dramatically greater than NBA LED (over 4x greater).

There are appropriate uses for white lighting. Where more accurate color perception is needed or desired – such as in outdoor eating or product sales areas, sports facilities, or areas used for significant social activity after dark, white lighting or a mix of amber and white may be appropriate. But the benefits of white lighting, and the need for its use, are often significantly overstated.

Even in uses that use low-impact amber sources, in most circumstances such applications also receive illumination from other lighting, such as automobile headlights or spill from signage, entryway and interior storefront lighting, which can provide adequate color perception.  The decision to use white sources should always give a fair and balanced evaluation of the plusses and minuses.

As clear as the benefits of amber lighting are, why don’t others like DarkSky International clearly advise its use?

This is a vitally important question, and is discussed in some detail on our page Why Isn’t There More Amber Lighting.

Parking lot illuminated by amber (LPS) lighting and white light spilling from signs and storefronts

For the best in dark-sky friendly commercial and roadway fixtures, see our Dark Sky Commercial Lighting Products page. Do right by the night!

 

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