The pathogen-neutralization technology, developed by The Johns Hopkins University Applied Physics Lab, Laurel, Md., has passed proof-of-concept tests that involved retrofitting it into an existing HVAC system. The Bio-Defense Research Group Inc., Upper Marlboro, Md., has licensed the technology.

APL's Safe Building system works this way: Pathogen-laced air enters a reaction chamber attached to an HVAC unit. That air mixes with small organic molecules that have been radiated by UV and converted into free radicals. Water sprayed inside the chamber mixes with the air and free radicals. The mixture then shoots through a wall of porous metal foam where everything is neutralized.

"We have shown excellent neutralization of stimulants for bacteria, viruses, and spores," says Project Manager Richard S. Potember of APL's Research and Technology Development Center. "Current testing involves seeing how the technology functions in full-size commercial HVAC systems, and the results are good. We're seeing that the technology can easily scale up to handle real-world environments."

In fact, BDRGI is using data from APL's prototype stage to build a system that works effectively in commercial-size buildings, such as hospitals where it tackles staph and other infections. Other applications could include cruise ships and airplanes.