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Electricians and emergency personnel frequently require self-contained lighting of various types when responding to emergencies in situations where power has been interrupted or where no electricity is available. Whether the area needing illumination is small or large, a wide selection of portable lighting options is available, including the simple flashlight, compact battery-powered work lights for small spaces, and portable light towers with and without self-contained generators for illuminating large indoor and outdoor spaces. In addition, there has been an increase in the selection available of “explosion-proof” lighting.
Flashlights
Whether at home or on the job, a flashlight often is the first temporary light source those in the dark reach for when power fails. The simple, handheld design offers many advantages over some of the larger, more powerful lighting sources. For example, flashlights can brighten small, hard-to-access areas where larger work lights can’t be used. Every electrician has one or more flashlights on a tool belt or in a tool box because it is often the easiest and most convenient way to illuminate a dark area.
Small flashlights can slip into pockets and are available for a few dollars. Home improvement stores stock a variety of sizes and brands suitable for the workplace. Many consider sleek Mag-Lite (www.maglite.com) flashlights to be top-of-the-line products.
Several tool companies well known in the electrical market—e.g., Klein, Milwaukee, DeWalt—have large selections of flashlights in their product lines, many of them using lithium-ion batteries powering clusters of light-emitting diodes (LEDs). Makita (www.makita.com), for example, offers more than 15 flashlight models, using various types of lamps and LEDs, powered by rechargeable nickel-cadmium (NiCad) and lithium-ion batteries.
Portable personal lighting
Portable personal lights are a step up from flashlights in both size and power. Cordless models are available in smaller sizes that may rival the traditional flashlight; however, as the potential lighting intensity increases, a power connection usually is required.
You may be wondering what the difference between flashlights and portable personal lights is if cordless models have begun to blur the line in size. While the user must hold flashlights, a base, pedestal mount, small tripod or tower may support a portable personal light. On smaller models, the battery pack may serve as a base or stand. Larger one-lamp lights can be mounted on a frame with wheels to maintain portability.
Compact balloon light models, which house lamps in an inflatable, opaque “balloon,” are lightweight and portable and provide nearly shadowless, glare-free illumination and can operate off a 20-amp (A) circuit or small generator.
The popular DeWalt (www.dewalt.com) 18-volt (V) cordless “snake light” has a flexible neck that allows the direction of its wide-angle beam to be easily adjusted. The flexible neck also can be wrapped around a pipe or ceiling rafter to suspend the light.
Petersen Brands’ (www.petersenbrands.com) Wobblelight sits on a rounded, counter-weighted base that rights itself if knocked over. A shock absorber protects the fluorescent lamp from damage, and an internal ventilation system cools exterior surfaces to prevent burns.
Larson Electronics Magnalight (www.magnalight.com) offers a selection of emergency lighting products including personal lights, light towers and explosion-proof lighting; many incorporate LED technology.
“For confined spaces, LED lights are popular now because they maintain a cooler temperature,” said Rob Bresnahan, president, Larson Electronics’ Magnalight. “Cooler temperature lights eliminate the risk of operators burning themselves, while reducing the risk of causing flammable vapors or dusts to ignite in hazardous locations.”
Use of high-wattage incandescent lights is fading due to these heat risks, vibratory failure and legal issues, he said.
“Metal halides continue to dominate large, outdoor work-area applications, since the dollar-to-lumen ratio is attractive,” Bresnahan said. “However, slow startup times for metal halide makes it for scene lighting and areas where power can be interrupted frequently. Finally, metal halide lights require high-voltage power sources, which may not be available in all areas, may require special skill sets to implement, and present risks in the event that a power line is cut.”
Several factors contribute to the growing popularity of LED usage, he said.
“LED lights can operate on low voltage, preserve safe working environments with instant-on capabilities and can require nothing more than deep-cycle batteries for power. Forward projection of LED light output can be comparable to that of metal halide. However, the dollar-to-lumen ratio based on cost of acquisition is much higher with LED lights. Even so, the total cost of ownership, including maintenance, is much lower for LED lights,” Bresnahan said.
Molex Inc. offers a wide selection of Woodhead (www.woodhead.com) work-site lighting, including hand lamps, light strings, tube lamps, wide-area portable lights, and general-, wet-location, and hazardous-duty lighting.
“There are many different types of lighting, each using many different technologies,” said Scott Hagen, Molex global product manager. “Today, fluorescent and incandescent seem to be the most frequently used technologies for portable lights used in confined spaces and hazardous locations. The reasons for this include the long development pipeline for new technology and next-generation products and the slow adoption in most applicable industries due to untested new products. Because these technologies have been around for a very long time and are proven in these environments, they continue to be frequently used.”
Explosion-Proof Lighting
Explosion-proof lighting is necessary in areas where flammable gases, vapors or other explosive materials that could be ignited by heat or spark are present. Many types and sizes of explosion-proof lighting are available, including flashlights, light strings, work lights and light towers.
“Explosion-proof lights are designed to contain spark and generate heat below certain rating thresholds,” said Rob Bresnahan, Larson Electronics’ Magnalight. “Operators can match the light’s specifications to the type of hazardous area they operate in, based on the materials present and how often they are present.”
Molex’s Scott Hagen said there are many types of product designs that will prevent or significantly reduce the likelihood of creating an ignition source; explosion-proof is just one of them.
“Explosion-proof lighting generally refers to fixtures that, when filled with explosive materials in hazardous concentrations that have been ignited, will contain the flame and hot gases sufficiently so that the atmosphere and surfaces outside the fixture will not ignite as well,” Hagen said.
—J.G.
LED safety products are making a big difference in the hazardous location market and other markets, Hagen said.
“Two great things about LEDs are the low-energy consumption and their ruggedness,” he said. “However, the commercially available LED technologies that are being used in products today are not yet significantly more efficient than fluorescents. The technology leaders are developing better and higher output LED packages, primarily for area lighting. But, when you consider portable hand lamps, the higher output lights are going to create more heat. For something you put in your hand, this is not a good thing.”
Hagen said because development and certification of hazardous location products takes much longer than regular products, the integrated LED technology will tend to lag behind the general market by a year or more.
“More validation of a concept usually should be done before the investment in a new hazardous location product as it is very expensive,” Hagen said.
Light towers
Light towers can brightly illuminate large indoor spaces as well as outside areas.
Multiquip (www.multiquip.com) is a major supplier of balloon work lighting units and trailer-mounted light towers.
“Halogen and metal halide lamps are the most popular for all types of lighting applications,” said Luis Torres, Multiquip product manager. “Both are very dependable and produce a sufficient amount of light; however, each has its pros and cons.
“Halogen lights cost less, but their life expectancy is about 200 to 300 hours,” he said. “They light up instantly and provide a pure white light.
“Metal halide costs more than a halogen; however, it will outlive a halogen light by 40 times (10,000 to 12,000 hours). A metal halide lamp produces more light and is much smaller, [which is] great for tight areas,” Torres said.
While LED lighting is gaining acceptance in many applications, Torres said the low lumen output of LEDs has prevented the technology from catching on in the portable lighting industry.
For indoor lighting, Torres cites Multiquip’s balloon light model with a durable 400-watt (W) metal halide lamp, which produces up to 14,000-square feet of 360-degree, glare-free illumination. The unit features an electronic ballast, which makes the unit lightweight and easy to handle while providing easy connectivity to standard 120V outlets. A smaller unit is available for confined spaces. A selection of balloon units is available for outside use, Torres said.
“Two models are available offering 1,000W metal halide bulbs and 360-degree, glare-free lighting,” he said. “A cart-mounted model can accommodate a generator for easy portability. Workstation models incorporate work stands that can be quickly set up and moved around job sites. Equipment has electronic ballast designs which substantially reduce the weight of the units and operate using standard 120V outlets.”
Terex Aerial Work Platforms, a business segment of Terex Corp., markets four trailer-mounted light towers for outside lighting, and in February, it introduced two new LED towers.
The four models in the established light tower line use 4,000W metal halide bulbs, which can illuminate up to 7 acres, said Jeff Weido, senior product manager.
Masts in stored position facilitate transporting units and are easily raised for operation. Galvanized outriggers with preset position stops allow quick and proper spacing. Plus, an internal storage system for lighting fixtures provides safekeeping and protection during transport.
“Mast rotation of 350 degrees permits pinpoint positioning of the light. Drawbacks of metal halide lights are that they take time to heat up and cool down, and they require proper disposal because they contain mercury.
“LED technology offers many advantages over traditional metal halide lights, providing immediate lighting, while metal halide lights have to ‘heat up’ to turn on. Light pollution and glare are reduced, providing ample lighting for most applications,” Weido said.
The two battery-powered LED light towers provide end-users with up to 10 hours of run-time per charge.
“LED technology,” Weido said, “offers the benefit of immediate lighting with crisper lighting capabilities compared to 4,000W metal halide models. Battery-operated LED light towers eliminate engine noise and emissions. Low light pollution and sharp side cutoff reduces road glare to passing motorists. The LED lights last 50,000 hours, five times longer bulb life compared to metal halide lights.”
GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at [email protected].
About The Author
GRIFFIN, a construction journalist from Oklahoma City, can be reached at [email protected].