A study published in the Lancet Medical Journal on Nov. 29, 2003 revealed that ultraviolet germicidal irradiation (UVGI) in the cooling coils and drip pans of ventilation systems kills germs that cause sick building syndrome. The shining of UVGI lights, manufactured by Sanuvox Technologies, resulted in a 99% reduction of microbial and endotoxin concentrations on irradiated surfaces within the ventilation systems. Sick building syndrome, blamed for irritation of eyes, throat and nose as well as respiratory illnesses such as asthma, affects about 4 million North Americans, according to the report.