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The latest in the National Lighting Product Information Program's (NLPIP's) Lighting Answers series, Lighting Answers: Light Pollution, is now online.

The report provides pointers to lighting professionals about how to minimize the effects of light pollution.

The three elements of light pollution are covered in detail. These are:

Sky glow
Light trespass, and
Glare.
Did you know, for instance, that there are two types of glare? The worst is disability glare, and the lesser evil is discomfort glare.

You can learn more about the three elements of light pollution here.

For a snapshot of states with legislation or pending legislation on light pollution as of January 2003, check out the color-coded map of the U.S..

One section of the publication shows how low-mounted lights can reduce spill light compared to high-mounted lights.

Other information provided in the publication include:

The Illuminating Engineering Society of North America (IESNA) cutoff classifications for full cutoff, cutoff, semi-cutoff and noncutoff;
An explanation of why , except for the full cutoff designation, the IESNA cutoff classifications are not a good indicator of direct uplight, because glare control was the original reason they were developed;
An explanation of the difference between full cutoff and fully shielded.
To more fully explore topics on this issue, read the index for the NLPIP's Light Pollution Sitemap.