WASHINGTON - In protecting buildings from potential chemical or biological terror attacks, an ounce of prevention may be worth a pound of sensing. Since the 2001 anthrax attacks, research has focused on developing improved sensors to detect chemical or biological terror agents. But these devices themselves cannot head off terrorist attacks, and while they should be part of an overall protection strategy, reliance on such technology can create a false sense of security, warns a Georgia Institute of Technology researcher.

Protection for public spaces such as airport terminals and shopping malls needs a "systems engineering approach," argues Jiri (Art) Janata, a Georgia Tech professor of chemistry who specializes in sensing and analytical instrumentation. That systems approach would include central command centers, response strategies tailored to the facility, protection of water and air circulation systems - and neutralizing and sterilizing chambers built into air circulation systems to limit the spread of terror agents.

Janata discussed these issues in a presentation, "New Strategies for Analytical Chemistry and Biochemistry in Homeland Defense," at the annual meeting of the American Association for the Advancement of Science.

"Correctly applied technology can improve security, but incorrectly applied technology - such as reliance on sensors that may or may not detect the actual agent being used - could create a false sense of security," Janata said. "We need to think about everything in terms of a systems engineering approach. Very little has been done to integrate comprehensive systems."

Using sensors to protect public buildings faces two major challenges: there are too many potential chemical and biological agents to reliably detect, and even with the fastest sensors, some people will become victims before the sensor can respond and an alert can be sounded.

Based on that realization, agencies such as the Defense Advanced Research Projects Agency (DARPA) have been promoting the concept of "immune buildings" that actively protect their occupants. This protection would come both from making buildings less attractive targets and from automated systems that would remove toxic agents from the indoor air.

"Almost every public building in the United States has a heating and air conditioning system that circulates the air," Janata noted. "Not only does that refresh the air, but it also provides a vehicle for introducing both chemical and biological agents. The concept would be to insert into that HVAC system a sterilization chamber that would disable the biological agents and decompose the chemical agents."

A chamber exposing the air to ultraviolet light could inactivate most biological agents. And because of their reactive nature, most chemical agents could be neutralized with a small number of chemical processes built into filtering systems.

"Some such technologies already exist," Janata said. "With some additional development, they could be implemented in public spaces."

Publication date: 03/07/2005