One advantage of Sandia’s detection capabilities is to couple enhanced bioaerosol detection with other systems to reduce false alarms.
Most chemical detectors from commercial vendors use laser-induced fluorescence (LIF)—which offers speed and sensitivity—to detect bioaerosols. However, because LIF systems are not highly selective, they tend to generate an unacceptable level of false-alarm rates.
Under funding from the Department of Homeland Security, researchers from Sandia, Yale, and the Army Research Laboratory (ARL) are studying the chemical and physical properties of the particulates that are leading to the LIF sensor false alarms. Specifically, Sandia is operating a sensor testbed created by Yale and ARL at a major international airport.
The testbed collects and concentrates particles in the airstream and measures their fluorescence spectrum, providing input to an algorithm that determines whether a particle should be retained for further analysis. This algorithm helps identify particles that would lead to a false-alarm rate.
Analysis of these "false-alarm" particles is yielding information on their chemical composition. This information can be used to explore ways to suppress the false alarms.
Fluorescence-based bioaerosol sensing project seeks to lower false alarm rates – Sandia News Release, November 20, 2007
These optical-based systems also can be significantly reduced in size without sacrificing performance by tapping into integrated microsystem capabilities. Sandia’s micro-optical, micropower, and general microtechnology capabilities are being advanced through our MESA Initiative.
