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Benjamin Prichard, Holophane Lighting
Newark, Ohio

Dear LASN: Dark Skies is a good idea, but street lighting is not the bad guy in this overall problem. The cutoff luminaire used in most streetlights allows a maximum of 2.5% of its light output above 90%. A 150 watt HPS lamp in a cobra head style luminaire has a 16000 lumen output which can have a maximum of 400 lumens above 90% minus the light loss factor of approx 70%. This translates to less than 280 lumens above 90 degrees which is equivalent to a 25 watt incandescent lamp. The major bad guy is the reflection of light from the pavement and buildings. Another major contributor is sports lighting. Street lighting is the best and most efficient way to protect the public on our streets from accidents and crime. Modifying the light distribution to eliminate this component will drastically affect the remaining distribution components creating the need for more lighting fixtures which in turn will create more reflected light from pavement up at the skies. Since the upward component is such a small factor we feel it is counter productive to require a full cutoff light distribution.

Marvin Wittin, Sentry Electric Corp
Freeport, New York

Dear LASN: The issues raised by the IDA, especially the pollution of the skies from excessive uplight and the safety issue stemming from the abundance of glare associated with many outdoor lighting products, are truly important issues. These issues also touch on the efficiency rating and general lighting design principles currently employed in the design process. It is my opinion that the industry should and, I hope, will deal with the ?EUR??,,????'?????<

Ron Lahner, Pennsylvania Globe
North Branford, Connecticut