AMERICA IS SUFFERING FROM AN EPIDEMIC OF SICK BUILDINGS. Poor ventilation and a buildup of bacteria in heating and air-conditioning passages can lead to respiratory and other illnesses. Until now, the only surefire remedy was to rip out the old systems and install new ones--an expensive proposition that caused many building owners to balk.
Yogi D. Goswami, a University of Florida engineering professor, says he has developed a stunningly simple, inexpensive solution: a system that forces air in the ventilation system through a filter coated with titanium dioxide--a common chemical powder used in toothpaste--then zaps it with ultraviolet light. Together, the two steps break down volatile organic compounds (VOCs) that build up in the air while killing bacteria that lurk in the ducts. The system can be installed easily in existing ducts or placed in new construction. Goswami has applied for patents and hopes to find a manufacturing partner.