One of the largest manufacturers of denim in the U.S., Avondale Mills processes raw cotton into denim cloth at nine plants in the Graniteville area. "At some of our plants, we had problems with lint packing itself into the ballasts of the existing fluorescent luminaires," says Paul Locklair, corporate electrical engineer. "The last thing we need in a cotton mill is to create a spark."
The company chose to install Prismalume Enclosed 400W luminaires from Newark, OH-based manufacturer Holophane throughout the addition. The metal halide units' enclosed optics are suited to the mill because glass is inert. Since the installation, the plant has experienced no problems with dirty luminaires due to the static electricity which can attract lint to lamps.
A challenge to installing the luminaires was placing them where they would minimize shadows created by the large amount of ceiling ductwork in the facility. "Employees work with individual yarns that must go through the looms," says Locklair. "They must be able to see broken ends or if ends are not tracking correctly. The dark cloth makes this difficult."
Shadows were minimized by mounting luminaires so they would provide 20% uplight to illuminate the open-truss ceiling. Because of varied ceiling heights caused by a sloped roof, each fixture was stem-mounted to maintain a 19-ft. height from the floor.
The company installed a different type of luminaire at its nearby 280,000-sq.-ft. Townsend plant. Enduralume luminaires with 400W metal-halide lamps and enclosed optics were used to retrofit an existing 8-ft. fluorescent system with lint build-up in the ballasts. Visibility was also substandard here.
"To provide required light levels, the fluorescent lights had been placed very close to the machines, which created a dark, cavernous ceiling." says Locklair. To improve workspace light and eliminate the cavernous look, the stem-mounted Enduralume luminaires were positioned 17 ft. to 19 ft. above the floor. High-angle light from the fixtures now illuminates the ceiling, and provide 75 footcandles of light overall.
"The system has updated the plant's appearance and made it much brighter," says Locklair. "We've seen a slight increase in production because the aesthetics are better. Employee morale has improved, too. It's hard to place a dollar value on how much it's worth for employees to have a desirable work environment."
An added benefit is that the efficiency of the luminaires has reduced the level of energy Avondale Mills uses at all of its plants, and allowed the company to receive a highly competitive rate for electricity.
