In the warm, humid south Texas environment, mold and mildew can be persistent problems in educational and other buildings. Outbreaks of fungus and mold have been reported in many schools here and have even, in worst case examples, resulted in closures.

At the Rizzuto Elementary School in LaPorte, an operation & maintenance (O&M) program was helping keep mold in check. But remedial measures showed no promise of eradicating mold and mildew problems, until the air handlers were outfitted with high-output, hvac-style UVC lights. The devices have helped solve a costly maintenance problem, while also proving to deliver energy and operational savings.

Despite several programs designed to eradicate mold buildup in the hvac systems, the school was still searching for a way to permanently remove the threat of the spread of mold spores. The school learned of high output UVC devices from Steril-Aire™, Inc. that are designed to eliminate mold and bacteria in air-handling systems and remove coil and drain pan debris. By providing a continuous form of source control, UVC showed promise as a practical and effective solution to this daily maintenance problem.

After cleaning the coil and installing the UVC lights, five months went by without a problem; and an inspection uncovered no mildew, fungus, mold, or odor. Due to the drastic drop in maintenance problems, the hvac department received the green light to install UVC throughout Rizzuto. Everyone from teachers to the principal has been pleased with the results. The maintenance work controller has commented on the lack of complaints from this campus.

Though the UVC lights were installed specifically to combat mold, mildew, and fungus, another unanticipated benefit has been a drop in energy usage. As each AHU was outfitted with UVC, the energy management system (EMS) began to throttle back on chilled water usage. This system works by measuring individual room temperatures. The more sensors it has calling for cooling, the greater the volumes of air it delivers. The further from setpoint the AHU discharge is, the greater the amount of chilled water it pumps. More air and more water at a lower temperature means much more energy consumed.

Rizzuto realized an apparent energy saving of $7,565. According to the school administration, there is another, perhaps more important benefit to the use of high-output UVC devices in schools. Absenteeism has dropped in areas where UVC is used, and the teachers do not complain of environmental quality, even where physically challenged students are taught. In the future, the school district hopes to compile enough statistical evidence to quantify this claim.

Information contributed by James Freeman, hvac foreman for the LaPorte Independent School District, LaPorte, Texas. Freeman is a chapter president for the Association for Facilities Engineering (AFE) and a member of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

Publication date: 08/06/2001