Open-Path Spatial Ring Down Spectrometer for Chemical Vapor Detection

Physical Science Inc. (PSI) will develop a new approach to chemical vapor detection based on a novel open-path sample cell design. The PhaseI system level model predicts SNR supporting a probability of detection of 95% and a MTBFA of 168 hours for all relevant CWAs and TICs at the10 minute negligible MEG level at a 20 s measurement time. In addition to robust detection, the system design can provide quantificationprecision to better than 4%. A breadboard system was designed, built and used to validate that the model-predicted signal trends wereobserved. A conceptual design and CDD were also generated for the prototype showing a pathway to achieving the size, weight, power andcost requirements. The sensor developed under this effort addresses the four major limitations of current man-portable chemical detectors:clear down delays, as well as limited dynamic range, precision and spectral library. The Phase II effort will focus on the design, build and testof 3 prototype sensors. The performance of these sensors will be demonstrated through a combination of laboratory testing againstsimulants and testing against live agents at a certified laboratory.