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Information Sheet l 39 (July � 998) Pa�e 3 of 4 Light output firom a fix#ure should b� limited �o more than 1 S degarees below the ho�izontal p�ane. Any attempt to �oodlight objects at a distance of more than 4 times the height of the l�ght fzxture creates glare and light trespass, and decreases visibility and safety. There needs �o be a footcandle limit {such as 50 fe for con�enienee s�oa�elgas �tation canopies) to stop this ratcheting war and help impxove visibility at night. Why should SS fc be needed outdoors when less than 50 fc are required indoors? Billboards and signs should be lit from the top down. The practice of ligh�ing biliboards from the bottom up seems to be more for the convenience of the service company than anyone else. Even a casual inspection of bottom-lit billboards reveals that the majoriiy of the light is escaping into the sky. Billboard �ighting can be accomplished from the top down, and with far less light by using fixtures that accura�ely d�rect th� light at the sign face. A good outdoor lighting code or ordinance could help a community save substan�ially (50% or more) on energy use and dollars spent �o operate outdoor lighting. Gities Iike Tucson, Arizona have already demonstrated haw it can be done. The reasons behind ihe regu�ation of outdoor Iighting should be clearly stated in such ordinances. For example: . The improvement of safety by elim�nating glare and pro�iding for a more even illumination • Saving energy by no� wasting light; using light only where and when i� is needed Light levels should be downsized to no more than the IES (I�luminating Eng�neering Society) recommended levels. In March of 1997, from downtown Tuc�on, I obser�ved Comet Hale-Bopp with a 20 degree tail magicaily suspended over the palm trees. I remember wishing that I could shaare �his experience with every city mayor and council membe�. The need for a safer environment, energy savings, and improved aesthetics -- while all desirable -- seemed to pale before the magic of this wondrous celestial visitor, Comet Hale-Bopp. With considered thoug�t and planning, any city could offer its citizens such sights, and the many other advantages of good outdoor lighting. John Gilkison http://��vww.darksky.or�/infashts/is139.htm1 6/20/2005