CHEMICAL MICROSENSOR FOR AUTOMATED, LONG TERM MONITORING OF CHEMICAL AGENTS AT VERY LOW CONCENTRATIONS

A CHEMICAL VAPOR MONITORING SYSTEM, INCORPORATING STATE-OF-THE-ART CHEMICAL MICROSENSOR AND MICROCOMPUTER TECHNOLOGIES, WILL BE DESIGNED AND OPTIMIZED FOR THE AUTOMATIC, CONTINUOUS, LONG TERM, LOW LEVEL MONITORING (BELOW 0.01 MG/M3) OF CHEMICAL AGENTS. THE INITIAL DEMONSTRATION UNIT WILL BE OPTIMIZED FOR HD, GB AND CD (AND THEIR SIMULANTS). SURFACE ACOUSTIC WAVE (SAW) MICROSENSORS WILL BE USED AS THE AGENT DETECTORS, AS THEY MEET ALL REQUIREMENTS FOR RELIABILITY, LOW MAINTENANCE, LONG SHELF LIFE, AND ARE SENSITIVIE TO HD, GB, GD AND MANY OF THEIR PRECURSORS AND DECOMPOSITION PRODUCTS. THE PHASE I INSTRUMENT WILL USE DUAL SAW SENSORS OPTIMIZED FOR HD AND G AGENTS. THE EFFORT WILL INTEGRATE THE SAW SENSORS INTO A SYSTEM THAT INCLUDES A SAMPLE CONCENTRATOR TO INCREASE SENSITIVITY AND A GC COLUMN TO PROVIDE SELECTIVITY. WORK INCLUDES OPTIMIZATION OF THE GC COLUMN TO SEPARATE AND MONITOR BOTH HD AND G AGENTS, OPTIMIZATION OF THE SAMPLE CONCENTRATOR, AND DEVELOPMENT OF SOFTWARE FOR AN ONBOARD MICROCOMPUTER TO OPERATE THE SYSTEM AND REPORT THE DATA. ALL STUDIES IN PHASE I WILL USE AGENT SIMULANTS. INITIAL GC STUDIES WILL BE MADE WITH AC, CK, PHOSGENE, AND THE LEWISITE DECOMPOSITION PRODUCT, ACETYLENE, TO DETERMINE THE FEASIBILITY OF OPTIMIZING THE SAME INSTRUMENT IN PHASE II TO MONITOR FOR THESE CW AGENTS AS WELL.