The "NRL-SAWRHINO": a nose for toxic gases

At the Naval Research Laboratory (NRL), surface acoustic wave (SAW) chemica l sensor systems have been in development since 1981. The primary focus has been the detection and identification of chemical agents and other toxic g ases or vapors, In the recently developed "NRL-SAWRHINO" system (Rhino, Gr. Nose), a self-contained unit has been developed capable of autonomous fiel d operation. An automated dual gas sampling system is included, for immedia te and periodic detection capability. The latter, utilizes a trap-and-purge miniature gas chromatographic column, which serves to collect, concentrate , and separate vapor or gas mixtures prior to SAW analysis. The SAWRHINO in cludes all the necessary electronic and microprocessor control, SAW sensor temperature control, onboard neural net pattern recognition capability, and visual/audible alarm features for field deployment. The SAWRHINO has been trained to detect and identify a range of nerve and blister agents, and rel ated simulants, and to discriminate against a wide range of interferent vap ors and gases. (C) 2000 Elsevier Science S.A. All rights reserved.