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Facilities Management and Design. Chapter 8 Lighting Systems. Basic lighting terms. Visible light ROY G BIV Color rendition Lumen Illumination Footcandles. Light sources. Natural light (sunlight) inexpensive and can contribute much to overall lighting needs drawbacks solar heat gain
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Facilities Management and Design Chapter 8 Lighting Systems
Basic lighting terms • Visible light ROY G BIV • Color rendition • Lumen • Illumination • Footcandles
Light sources • Natural light (sunlight) • inexpensive and can contribute much to overall lighting needs • drawbacks • solar heat gain • glare • fading and physical deterioration of fabrics • Common artificial light sources • incandescent lamps • electric discharge lamps
Incandescent lamps • Advantages • instant starting and restarting • low in cost • good color rendition • Disadvantages • short lifetime • poor efficiency • high operating cost • adds heat to building • Types • Conventional • rough service or vibration • Tungsten • reflector
Electric discharge lamps • Advantages • longer lifetimes • higher efficiency • low operating cost • Disadvantages • slow starting and restarting • higher cost • poorer color rendition • Types • Fluorescent • mercury vapor • metal halide • high- and low-pressure sodium
Lighting system design elements • Light levels • determined by the tasks or activities that will take place within a space • light levels measured by portable light meters; Illuminating Engineers Society, Illuminating Engineering Society of North America, and the American Society of Heating, Refrigerating and Air-Conditioning Engineers recommend minimum light levels • building area method vs. space-by-space method • dimming controls
Lighting system design elements • Luminaires • Components • Lamps • lamp sockets • ballasts (for electric discharge lamps) • reflective material • lenses or louvers • Housing • visual comfort probability • coefficient of utilization
Lighting system design elements • Color rendition • color of light affects appearance of surfaces, finishes, furnishings, etc. • color rendering index • Safety • lighting system must comply with local safety codes • all luminaires need adequate ventilation, clearance, and proper wattage • acryllic diffuser or tube safety shield for some lamps in some locations (kitchens, for example) • insufficient light • glare • widely varying light levels can be hazards • Emergency lighting • must comply with local codes, which are often based on the Life Safety Code and the National Electrical Code • a delay of no more than ten seconds is permitted • exit signs
Lighting system maintenance • Cleaning • replace HVAC filters to cut down on dust • semi-annual cleaning • destaticization • Replacement • incandescent lamps replaced more often than fluorescents • lumen depreciation • group replacement vs. replacement upon burnout • old lamps and ballasts must be disposed of properly • recycling of fluorescent lamps and ballasts available in some areas
Conservation opportunities • Efficient lighting • Control operating hours • Replace incandescents with fluorescents when possible • Turn off lights when not needed • EMS methods • Microprocessors/computer systems • photocell control • ultrasonic or infrared sensors • twist timers