New Lighting Demands Play Increasingly Important Role In Parking Facilities
Manufacturers, armed with advances in lighting technology -- as well as with studies on safety, visibility and nighttime vision -- are heeding the call for more energy-efficient, cost-justified lighting that not only promotes security in parking garages and surface lots, but also is "sensitive" to and enhances surrounding environments.
Although pedestrian safety remains key in illuminating parking facilities, the push to use more so-called Dark Sky fixtures is challenging some long-held notions of what constitutes a safe environment. Public perception may equate higher light levels with a greater sense of safety. However, the inclination toward "more obvious light" could result in what Dave Holladay calls a "vicious circle." The vice president and general manager of Quality Lighting, a manufacturer of outdoor pole- and building-mounted area lighting, Holladay said that "higher light levels often require higher-wattage lamps, which require higher pole heights and, consequently, create more light spillover."
While full cutoff optics and lower mounting heights help resolve issues of light trespass and sky glow, "they also necessitate a little more hardware to achieve required light levels," said Michael Imparato, president of Beacon Products, a manufacturer of specialized outdoor site lighting. "But uniformity and visibility are improved, which is the goal. Security is not enhanced by over-lighting a parking lot -- quite the contrary if there is high glare."
Uniformity of lighting and reduction of glare are essential to the proper operation and effective monitoring of parking lot and garage surveillance cameras, for one thing. "Parking lot lighting design has begun to encompass security and safety issues by catering to ... security equipment that requires certain light levels for image capture and transmission," Imparato said. "This includes low glare enhanced by infrared technology. Parking garages deal with these same issues, with the added challenge of height, uniformity and traffic-flow issues in a more confined environment."
Today's newest fixture designs offer optics, lamp options and a broad range of mounting heights that respond to these challenges with "better, more comfortable levels of illuminance than the industry has previously achieved," Imparato said. "These enhance not only actual levels of security and safety, but also the perceived feeling of safety and security. In addition, many lighting features have been combined with pedestrian and vehicular traffic-flow elements, such as signage and directional information, to make it easier to transit both outdoor and multi-level parking facilities."
While this confluence of safety and environmental concerns has impacted the development and selection of fixtures for parking applications, economics remains a vital concern. "In the world of outdoor area lighting, the manufacturer that can reach the minimum foot-candle requirements with the fewest number of light heads and poles usually wins," said Mark Carroll, a business unit manager for the ExceLine division of GenLyte Thomas, a manufacturer of commercial lighting fixtures. "Parking garage projects tend to focus on the dollar-per-foot-candle ratio," he said. "The balance is always unit performance and features versus purchase price."
Energy savings can play a part in the financial equation of lighting a parking facility. Because of metal halide's superior color rendering, which fosters a greater sense of security, it is fast replacing low- and high-pressure sodium as the lamp of choice. Its popularity has been spurred by electronic ballasts "that save more energy and increase lamp life," said Perry Romano, president of Varon Lighting. However, Carroll is also seeing a move toward induction lamps and new-type LED, which can project light when matched with new reflector technology, and that promise even longer lamp life.
Further savings may result from recent developments in enhancing fixture construction. "Milestones have been made in ensuring longer fixture life and peak performance by keeping corrosive or foreign elements out of optical systems; improving maintenance characteristics with creative access hardware; and by improving metal alloys, finish prep and final finishing," Imparato said. "Better technology has developed after seeing what acid rain, road salts and cheap alloys do to fixtures and their general lighting performance."
Lighting manufacturers have been impacted by a growing interest on the part of design specifiers and corporate or municipal clients -- partly spawned by the lower mounting heights -- in more attractive and sophisticated fixtures -- not only for outdoor facilities, but "even inside parking garages, where few people really notice them," Holladay said. Finish and color options have been expanded to accommodate the greater attention paid to the daytime appearances of fixtures.
Alice Liao is a freelance writer in New Jersey, specializing in lighting design and applications.
Article Abstract from May, 2004