Sick building syndrome is the carpal tunnel of the new millennium; a boone for malingerers who take every wheeze and sniffle as proof they are slowly being poisoned by their employer's HVAC system. But these days companies have more than mold spores to worry about. There is also the specter of bioterrorism and the threat of chemical agents or other toxins being purposefully introduced into a building's air supply.RAE Systems, a Sunnyvale, Calif.-based company, has introduced a line of wireless sensors called AreaRAEs, each about the size of a lunchbox, that can be deployed in a building to monitor and measure the air for the presence of volatile organic compounds, humidity and toxic industrial chemicals. The sniffers detect toxin levels at one part per billion, 600 times more powerful than the human nose. Each sensor continuously processes data and reports any problems to a central location in the security department. Together they make up a wireless network that gives the security department a complete picture of the building's environmental health, which enables faster identifications of problems and (most important) faster evacuations.Many of RAE's clients deploy the sensor networks for traditional air-pollution concerns such as manufacturing sites where paints and plastics are produced and breweries that have to monitor the carbon dioxide coming off the vats. However, Bob Durstenfeld, director of corporate marketing for RAE Systems, notes that they are starting to see a greater interest from federal office buildings, corporations and public areas that worry about being targets of toxins. For example, AreaRAEs were deployed at Reliant Stadium to detect toxic substances at the Super Bowl. "Any place where people gather makes for a good target. Our business is moving from indoor-air quality to indoor-air security as we start to see a marriage between security systems and IT systems," he says. RAE was selected earlier this year to provide toxic-gas detection, decontamination, indoor-air quality and security screening equipment to the Central U.S. National Medical Response Team, a Colorado-based division of DHS tasked with providing medical care following nuclear, biological and chemical incidents.With each sensor costing about $7,000, it's an expensive way to find out if your employee is faking a case of sick building syndrome. But with bioterrorism concerns on the rise, sensing networks have the whiff of a growing trend.