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Some bright ideas improve nighttime safety
In the wake of terrorist attacks and last fall’s sniper shootings, security is a hot topic in both commercial and residential markets. With security concerns on the rise, specifiers for commercial and residential products are moving toward increasing the overall amount of light.
Well-designed outdoor lighting can make people feel more secure, facilitate identifying intruders or suspects at crime scenes, highlight landscaping, plus create a pleasing ambiance.
With energy efficiency being another top priority, specifiers look for more energy-efficient lighting to reduce light output.
Steve Goldmacher, corporate communication director for Philips Lighting Company, said lighting in most parking lots is not done properly. Often poles are too far apart, creating pools of dark areas between them.
“Some older lots may have 15 poles 100 feet apart,” Goldmacher said. “Since light levels diminish at 50 feet, people who park at dead center will not feel as safe as they would near the poles.” He suggested a relatively easy parking-lot lighting makeover. Add some additional ground-level lighting to make the walk to one’s car safer. To reduce the cost of such an upgrade, utilize the existing wiring between poles. Decorative greenery strips between lanes, highlighted with special-effects lighting will create a more attractive and secure environment.
The same theory applies in residential lighting. Do not leave dark spots by placing lamps too far apart, or the section between could become a hiding spot for intruders. The lights should overlap so there are no dull, dark spots.
Unfortunately, most homeowners do not use a lighting designer, despite the fact that it would be beneficial if they did. Lighting designers understand both energy costs and ambiance issues. “Designers will make the area look good, without complicating things for installers. Designers know how to stay within the budget and help electrical contractors avoid surprises,” Goldmacher said.
Philips QL induction lamps offer multiple benefits for outdoor security lighting. The prime advantage is longer life, thus reducing maintenance costs for relamping. “QL has a lifespan of more than 100,000 hours, which equates to 15 to 20 years,” Goldmacher said. “If a light bulb is on for 12 hours a day, that’s 4,200 hours a year. Once the QL is in, it’s in.”
Pulse-start metal halide vs. high-pressure sodium
According to Jim LaPointe, Osram Sylvania HID product marketing manager, one ripple effect of Sept. 11 has been the increased use of area flood lighting. Customers want to ensure their facilities are properly lit for safety and security reasons and are being more vigilant about replacing extinguished lamps. The sales of HID lighting surged in the last quarter of 2001.
In recent years, we have seen a dramatic shift from yellow high-pressure sodium (HPS) to white metal halide lighting, especially in parking lots and pathways. It is easier to discern colors more accurately under white metal halide lighting. Under HPS lighting, a red automobile may appear brown or blue, making it more difficult to describe suspects or autos at crime scenes.
The ability of a light source to render color accurately is known as Color Rendering Index (CRI). A typical incandescent lamp has a CRI of 100. The closer to 100, the truer colors will look. Metal halide CRI ranges from 65 to 85, whereas HPS lamps’ CRI is 22.
LaPointe said the Lighting Research Center at Rensselaer Polytechnic Institute in Troy, N.Y., performed studies that indicate night vision is improved under metal halide light sources. The output of metal halide light sources in the blue region of the visual spectrum enhances the eye’s ability in low light conditions.
New Sylvania dual-wattage Metalarc Pulse-Start lamps can be run at a lower wattage when an application calls for increased energy savings or at a higher wattage when improved light output is needed. When dual wattage is not needed, Sylvania offers a range of high-performance single-wattage Metalarc Pulse-Start lamps.
Metalarc low-wattage (39W to 150W) pulse-start lamps allow the high white light output and efficiency of metal halide lighting to be used in a wide variety of applications.
LaPointe said Metalarc Powerball Ceramic lamps meet today’s critical color needs by combining conventional metal halide pulse-start characteristics such as good efficiency and long life with improved lamp-to-lamp color consistency and high CRI.
Phil Henry, product manager for Crescent Stonco, a division of Genlyte Thomas, agrees the trend has moved toward pulse-start metal halide lamps or white light. “The metal halide lamp family has the brightest future and often competes with high-pressure sodium for use in streetlights and security lights. Although metal halide lamps have had some limitations, recent technology advances are addressing the operating limitations and improving performance,” Henry said.
“In addition, pulse-start metal halide lamps provide the same light output as similar wattage HPS lamps and produce a bright white light at a reduced wattage, which is perceived as brighter and offering better ability to see.”
Floodlighting vs. shoebox
Shoebox lighting continues to be recommended over ubiquitous floodlights. Shoebox lights have a cut-off beam pattern that only illuminates and beams down on a given area, whereas the floodlight illuminates a broader area, increasing light pollution. Shoebox lights keep the light where you want it and reduce glare, which has a tendency to negatively affect visual acuity.
According to LaPointe, the newer fixture designs with improved cut-off angles have driven lamp manufactures to develop smaller-diameter light sources and improve horizontal operation. The smaller-diameter lamp allows the fixture designer to control the fixture optics. The horizontal operation allows the removal of convex lenses from the fixture.
Philips’ Goldmacher also recommends selecting cut-off fixtures that direct light downward, especially in urban areas with low-light requirements. “If there is no uplight, the sky is clearer without haze light diffusing it. This contributes to a clearer atmosphere to see the stars,” he said.
Outdoor residential lighting
Residential security is a growing concern, and many streets are not well lit. Lutron Electronics Co. Inc. has added a number of new features to its RadioRA wireless home dimming system which uses radio waves to communicate. Because RadioRA does not rely on power lines for signal communication, it works when electrical surges, noise and interference disable other wireless systems.
Lutron’s special RadioRA package includes five lights of control, a bedside master control, a garage entry control, and two car visor transmitters that can be programmed to turn lights on or off. When owners approach their dark homes at night, they press a button to turn on outside and inside entry lights.
“RadioRA has sold well—people feel more secure coming into a lit home,” said Roger Stamm, Lutron’s marking manager of residential systems. “In addition to security, convenience is a selling point. You simply push a button to turn lights on when you arrive and off when you leave. The typical range of the car transmitter is 150 feet.”
RadioRA products start around $1,000 and can go from $10,000 to $12,000 for systems targeted to existing homes in the $250,000 to $500,000 price range. The product can be retrofitted into any house, and contractors who know about it also sell it to new homeowners. Lutron provides a factory-trained installer program and sales tools for contractor demos. “We list factory-trained installers on our Web site and extend the warranty for their customers,” Stamm said. EC
WOODS writes for many consumer and trade publications. She can be reached at [email protected].