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Home My WebLink AboutInfo on lighting Information ShQet 122(May 1997) http://www.darksky.org/resources/information-sheets/is122.htm1 05/97 4� International Dark-Sky Association -- Information Sheet 122 Examples of Good and Bad Lighting Fixtures � =o� top ir � �. k. « 8^°'� n � glass �d� s�y�`. S1dC Y panels GOOD Even post-top ornamental fixtures, like GOOD The Yorktown, this Salem Cutoff from another ornamental GE Lighting, can be cutoff from Emery Fixtures, BAD Non-cutoff fixtures with clear panels and also has clear panels like this "acorn" and bulb located above ornamental cause light lamp/reflector located ollution. above. for maximum glare and P spill light control. �.�_ _ . ...q �� ;I 1� _..- �a ,. GOOD Ftat-lens cobra " ��` head fixtures, like this GOOD This new American Electric Series generation of flat-lens BAD The ubiquitous 125 Roadway Cutoff cobra head fixture from drop-lens cobra head luminaire, provide American Electric, call luminaire produces a level excellent roadway the DuraStar 2000, of glare and uplight that is lighting with greatly provides superior both unacceptable and reduced glare and no lighting uniformity at unnecessary. uplight. standard mounting heights and spacings. 1 of 3 11/28/2007 9:03 AM Information Sheet 122(IUIay 1997) http://www.darksky.org/resources/information-sheets/is122.htm1 w 1 � � r F °. GOOD The Hubbell ��' GOOD Many existing Skycap turns any gqD Barn Light style standard Barn Light dusk-to-dawn security into a full-cutoff light fixtures are very inefficient, lights and residential With wide area sending about 20% of the streetlights can be light upward and another coverage. retrofitted with the 20% horizontally outward, Hubbell Skycap. creating glare. t�t�q�(�j �IIIIAI'Iplhi �ii�i�im�i�i BAD (sometimes) The �" �'� telltale sa lens ives this GOOD Flat-lens shoebox ��►�n� °• - �• g g fixtures come in many luminaire away as a forms; square, GOOD Post-top possible problem. If the rectangular, circular, etc. flat-lens shoebox lens is clear and very All control the light with fixtures like this one shallow, and the bulb internal reflectors. Glare provide good area wattage is not too high, and light trespass are illumination without this type of light can cover minimized; no uplight is light pollution. a wider area without too produced, much glare or uplight, but beware! � '� � � �� s ' � . - �, ��, ��s GOOD Full-cutoff wall GOOD Recessed packs such as this canister lights built into mcPhilben 101 Wall the eaves or canopy of BAD Wall packs like this Sconce make excellent a house, garage, or should never be used. entryway and building other building is the They produce enormous 2 of 3 11/28/2007 9:03 AM Information Sh�et 122(May 1997) http://www.darksky.org/resources/information-sheets/is122.html perimeter lights, and there is enough forward first choice for lighting throw that adequate building exteriors. 9�are and uplight. lighting is provided for near-building parking. �� _ � � ��ry r. � - �;, �; �;�,._., ='f GOOD If floodlights must j� be used, they should always have top and side GODD Even sports gqD Unshielded shielding, and be pointed lighting can be done floodlights provide a trashy at least 45 ° below the well, if one uses cutoff ��prison yard" look and horizontal. light fixtures such as should not be used. these from Soft Lighting Systems. O IDA Inc., 3225 N. First Ave., Tucson, AZ 85719-2103 USA Telephone: 1-520-293-3198 Fax: 520-293-3192 E-mail: ida@darksky.org Web: www.darksky.org 3 of 3 11/28/2007 9:03 AM Information Sh�et 159 (Qctober 1999) http://www.darksky.org/resources/information-sheets/is159.htm1 10/99 International Dark-Sky Association -- Information Sheet 159 Shielding Floodlights Improving Performance to Prevent Glare, Light Trespass, and Light Pollution Outdoor floodlights are designed to "broadcast" illumination, to cover as much area as possible. The lack of"light control" in a floodlight causes many detrimental and unwanted side-effects, like: blinding glare, intrusion into neighboring homes and natural areas - called light trespass, and waste light up into the night sky - called light pollution . d Waste Light,Light Trespass 0 � 0 � � I Of .� n Task Areo Z ZY � ,_ _ _ � _ � � ----•-'� r -•-- � ... ... �__ ._____- �,.,� I �/ \ Too The floodlight's exposed light source (bulb) remains in direct view from most angles -which causes disabling glare. This compromises vision for pedestrians, drivers, or police surveillance. It also disturbs neighbors, disrupts nearby wildlife, and can be visible across great distances. A three-sides shield can be installed on the floodlight to create a horizontal visor as shown. The visor should just cover the light source completely. This incorporates a "light control" feature to the fixture, allowing more precise and efficient lighting for the task area. By shielding the distracting glare from the light source, the viewer can actually see the entire area better. The light can be contained within the property area, and kept out of adjacent properties. The light normally lost up into space is now redirected to the intended task area. Some manufacturers of floodlights offer attachable visor shields. They can also easily be made from flashing aluminum or stainless steel sheet metal. Once the shields are installed, floodlights can be re-aimed at night to properly "tune" the illumination to the property boundary<as shown below. Another added benefit from shielding floodlight glare is that it creates a more 1 of 2 11/28/2007 9:14 AM Information Sheet 159(October 1999) http://www.darksky.org/resources/information-sheets/is159.htm1 visually inviting appearance to an area, instead of a stark, trashy look resembling a prison yard. o �, ; � � o � � .n � s I a� c�� .� � �7 Task Area Z �n� F d�! L�: % ..:,....{. I{ � I ,.�i: �Ic �S- •.I.^'.u,k. �. M`� . 4 N�. � �PL•�� e .. �a� � �. I� P�� ^ r �, N�. ... "�l�"�. ' " rV � � x* '�i„ � �.. � tqt i 5"f �F '_ #.�' x �;��.�e.' •,;� �� '`��y;;i,.. �"i.. ��, . . . 5.y..�:� . . ... NOTE This sheet is intended to describe the best remedy for existing floodlights. For the best performance in new outdoor lighting installations, consider full-cutoff type fixtures instead of floodlights to avoid glare, light trespass, and light pollution. Produced by Bob Crelin O IDA Inc., 3225 N. First Ave., Tucson, AZ 85719-2103 USA Telephone: 1-520-293-3198 Fax: 520-293-3192 E-mail: ida@darksky.org Web: www.darksky.org 2 of 2 11/28/2007 9:14 AM