|
Air Conditioning Coil Nurtures Contaminants Preventative Technology Shines Light on Sick Building Sources
November, 2008
By Del Williams
High intensity ultraviolet germicidal irradiation (UVGI) can be an effective means of improving indoor air quality. It can prevent mould, bacteria or microbial growth in air-cooling units, air conditioning coils and drip pans, which are prone to moisture-caused growth, especially in humid climates.
Sick building syndrome is often blamed for a range of health problems including irritation of the eyes, throat and nose, respiratory illnesses such as asthma, headaches and fatigue. The cause of these and other ailments can be traced to microbial content in the air people breathe, caused in part by newer building design that closes the building off to outside air.
Forms of ultraviolet (UV) light have been used with mixed results in commercial properties to improve indoor air quality. High intensity ultraviolet germicidal irradiation (UVGI) is a refinement of the technology.
Unlike lower intensity UV light, high intensity UVGI shines at an intensity that's effective in penetrating the cell membranes of targeted micro-organisms, breaking their DNA structure and inhibiting reproduction. It can also help burn off particulate lodged inside air conditioning systems to increase airflow, while reducing maintenance and energy use.
In a study published in The Lancet Medical Journal, McGill University scientists found that shining high intensity UVGI purifiers on the air conditioning coil reduced overall sickness by 20%, reduced respiratory symptoms by 40%, and resulted in a 99% reduction of microbial and endotoxin concentrations on irradiated surfaces within the ventilation system.
"Installation of UVGI in most North American offices could resolve work-related symptoms in about 4 million employees caused by microbial contamination of heating, ventilation and air conditioning systems. The cost of UVGI installation could in the long run prove cost-effective compared with the yearly losses from absence because of building-related illness," the study stated.
The purifiers tested in the McGill study incorporate a parabolic reflector that focuses the energy forward like the reflector of a flashlight, directing high-intensity energy onto the air conditioning coils and drip pan. This destroys and prevents mould and other microbial growth.
By directing the UVGI in one direction, the parabolic reflector virtually doubles the lamp replacement time, which translates directly into reduced maintenance and operations costs. The parabolic reflector also protects plastics and wiring from destructive UV rays, and offers protection from breakage caused by high air velocity vibration.
The preceding article was provided by Sanuvox Technologies, specialists in ultraviolet air purification and UV coil cleaning, including the high intensity ultraviolet germicidal irradiation cited in the McGill University study. For more information, see the web site at www.sanuvox.com.
|