Construction work often must be done in areas without power and, therefore, without adequate light. Also, it often must be done outside at night. Following natural disasters and lesser emergencies, portable light towers enable rescue efforts and the restoration of essential power and communications services to begin without waiting for morning.


Electrical contractors have projects in large commercial and industrial buildings and warehouses, and they often have to install or service traffic and street lighting at night when vehicular traffic is lighter than during the busy daytime hours.


Many types of portable lighting are available, ranging from compact, battery-powered models on tripods for illuminating small work areas to large, generator-powered equipment on wheels or casters. Fixtures can contain one or more lamps, or they could have light-emitting diodes (LEDs)—an increasingly popular choice. The number of lamps in a fixture range from one to several, and the number of light towers using light-emitting diodes (LEDs) is increasing. “Inflatable” light towers with a balloon or bubble surrounding the lighting fixture are an option. A wide range of indoor and outdoor lighting models are readily available for rent. 


Several manufacturers make self-contained, towable models with four-lamp fixtures powered by an on-board generator that is operated by a compact on-board engine. They fill For example, Evets Oil and Gas Services, Girard, Ohio, a Valley Electrical Consolidated (VEC) company, owns four pull-behind light towers.


“We use them in situations where we need to light a small area,” said Brian Barnes, site manager at the company’s Hubbard facility, which is responsible for the organization’s mechanical and civil construction. Barnes manages tools and equipment and gets them to and from project sites.


When multiple lighting units are needed, light towers are rented, Barnes said.


“Much of our work is in daylight,” Barnes said. “But when projects require several light towers, renting makes good business sense. Renting frees us from investing in equipment that will only be used occasionally, and we get exactly what is needed for the job.”


No statistics are available, but it is likely that a large number of light towers are rented each day; United Rentals has an inventory of more that 22,000 light towers of the type Barnes describes (see sidebar, page 50).


Perhaps the most significant development in light towers are single-mast towers and LEDs as the light source.


“One notable change in light towers is the emergence of a vertical mast configuration, which Terex now offers as an option,” said Marie Engstrom, associate product manager for Terex. “A vertical mast tower is different than a traditional lay-down tower in that it stays upright and doesn’t rest over the cabinet when in the stowed position. This allows a smaller overall envelope for the tower as the lights no longer hang over the back of the trailer.”


Engstrom cited three key benefits:


• Simpler and faster setup and mast deployment with the use of an electric winch


• Accurate positioning of the lights by a mast that rotates both raised and stowed


• Increased shipping efficiencies with more units fitting on a truck, saving customers money


LED light towers are slowly gaining traction in the market, Engstrom said.


“The technology continues to evolve and become more cost effective,” Engstrom said. “As this happens, LED towers will continue to become more popular. LED light towers offer clean, crisp white light with instant on/off capabilities.”


[SB]Portability always will be an important light tower feature.


“This type of product can either be shipped on a flatbed truck or towed behind a vehicle,” Engstrom said. “Because light towers are used in such a wide range of locations, it always will be important that available models can be easily towed and maneuvered around job sites.”


Terex designs and manufactures light towers in a variety of sizes and specifications for standard and heavy-duty applications. The models equipped with metal-halide lights run off of a generator and provide 4,000 watts of light. Terex LED light towers can run off of battery power for silent operation and no emissions. LED light towers configured with a generator can save up to 40 percent on fuel. For the ultimate in flexibility,­ LED towers can also be equipped with both a battery and generator. Each Terex light-tower model comes with various options for different job-site applications, which include mast options, hitch configurations, cold weather kits and multiple power configurations.


“Our light towers are used in a variety of applications including construction and infrastructure projects, storm relief and community and sporting events,” Engstrom said. “Industrial heavy-duty light towers are commonly used in oil and gas applications as well as mining, all of which can involve electrical work. All of our models come with auxiliary power outlets, which can be used to power tools and equipment.”


Multiquip Product Manager Bruce Coleman said highly mobile lighting equipment—whether trailer- or cart-mounted—are crucial to the operating application. Multiquip provides diesel-powered mobile, modularly designed and conventional towable light tower/generators.


“Modular units offer power packages that include industrial generators and welder/generator design,” Coleman said. “Conventional light tower lines offer very compact, environmentally sound units. All of our light-tower models offer DOT-certified trailers, four 1-kilowatt metal-halide lamps for lighting, and they further provide options for diffused lighting.


“For various fields of construction, area security, entertainment and special events, we have witnessed an increased penchant for diffused lighting solutions and LED lighting options,” he said.


Coleman added that glare-free lighting requirements are often written into Department of Transportation specifications for street and highway projects; plus, noncaustic diffused lighting options add value for both construction personnel and the public in lighted areas. With design advantages of greater clarity, longevity, lessened power requirements, and safety, LED lighting options are becoming more practical and popular.


“The value of diffused and LED lighting cannot be understated,” he said. “As advancements in design pace upwards, and both product and operational costs go down, we can see a time where specifying these types of lighting solutions will be commonplace.”


Diffused lighting systems have a more finite luminance range compared to the conventional lamps of light towers, but their greater lucidity and glare-free signature significantly enhance work or event sites, he said.


“Safety, as it relates to on-the-job operations and surrounding activities, is particularly enriched with diffused lighting,” Coleman said. “The percentage of its usage continues to trend upward.”


Portable lighting by no means is limited to the light towers covered in this report.


Inflatable or “balloon” light towers have a semitransparent balloon around the lamp that distributes diffused light to the surrounding area, and are used for both indoor and outside projects. There are standalone balloon models and balloon diffusers that attach to conventional towers.


Explosion-proof temporary lighting in many sizes and configurations is available for working in areas where flammable gases and vapors and other explosive materials are present and could be ignited by heat or spark.


“Explosion-proof” does not mean that they can withstand an explosion, but rather that the enclosures have the ability to prevent an internal spark or explosion from causing a much larger blast, and they generate heat below specified rating thresholds. To meet the criteria for the explosion-proof rating, an enclosure must be able to contain any explosion originating within its housing and prevent sparks within its housing from igniting vapors, gases, dust or fibers in the air surrounding it.


All components are labeled on the nameplate with the distinct classification in which they have been tested and approved.