In a study published in The Lancet, McGill University scientists found that shining proprietary Ultraviolet Purifiers manufactured by Sanuvox Technologies Inc, supplied in the UK by Wright Hygiene Ltd, Glasgow. on the air conditioning coil reduces over all sickness by 20%, reduces respiratory symptoms by 40% and has resulted in a 99% reduction of microbial and endotoxin concentrations on irradiated surfaces within the ventilation system.
According to the study's leader, Dr. Dick Menzies of the Montreal Chest Institute “Ultraviolet germicidal irradiation, or UVGI, has been used to disinfect the air in hospital operating rooms and ventilation systems as well as meat-packaging plants and the pharmaceutical industry.”
Sick building syndrome has often been blamed for irritation of the eyes, throat and nose as well as respiratory illnesses such as asthma. Symptoms also include headaches, fatigue and problems concentrating. By reducing microbial contamination using Sanuvox Ultraviolet Purifiers, McGill researchers hoped to see a corresponding reduction in the levels of work-related illness.
After studying the effects of Sanuvox UV CoilCleaners in three Montreal offices over a period of 48 weeks, the researchers found it had a "substantial effect in reducing reported work-related illnesses," Menzies said.
A total of 771 employees from three different public and private buildings in Montreal were involved in the double blind study sponsored by the Medical Research Council and The National Institute for Occupational Safety and Health (NIOSH). Starting in 2001, the patent-pending Sanuvox UV CoilClean Purifiers were turned on for four weeks, and then turned off for 12 weeks. The cycle was repeated three times for a year. The use of the Sanuvox UV Purifiers resulted in a 99% reduction in the concentration of bacteria on irradiated surfaces within the ventilation systems. Temperature, humidity and ozone levels were unaffected.
“Sanuvox uses specific UV wavelengths to destroy biological and chemical contaminants in the air-stream and on the air conditioning coil. This study illustrates very well how our process destroys microbial contaminants. By using Aluminum Parabolic Reflectors, the Coil Clean purifiers are able to direct 100% of the UV Energy onto the coil without losing UV on the back-end of the lamp. The Reflector also protects plastics and wiring from destructive UV rays. This is how Sanuvox is able to deliver a high concentration of UV intensity to the air conditioning coil virtually eliminating and preventing any future growth,” said Dr. Normand Brais, President of Sanuvox Technologies Inc.
Wladyslaw Jan Kowalski, an architectural engineer at Pennsylvania State University's Indoor Environment Center, told The Associated Press the McGill study may be a landmark in proving the technique could be cost-effective in commercial office buildings.
Dr. Kowalski, who was not involved with the research, also said the approach could be useful in the broader effort to combat contagious diseases such as flu, SARS, tuberculosis and cold viruses. "Theoretically, if a large number of schools office buildings and residences were modified, a number of airborne respiratory diseases could be eradicated by interrupting the transmission cycle," he said. "Reducing the transmission rate sufficiently would halt epidemics in their path."