A PORTABLE INSTRUMENT FOR REAL TIME DETECTION OF AIRBORNE PARTICULATES

AVAILABLE INSTRUMENTS USED TO MONITOR AIRBORNE PARTICLES (SUCH AS DUST) ARE TYPICALLY INTEGRATING DEVICES WHICH COLLECT OVER LONG PERIODS -- HOURS TO DAYS. THESE DEVICES, SUCH AS PM-10 SENSORS, ARE ACCURATE BUT PROVIDE ONLY A TOTAL OVER TIME, AN AVERAGE CONCENTRATION. IMPROVEMENT OF AIR QUALITY REQUIRES DETERMINATION OF CAUSE AND MEASUREMENT OF THE EFFECTIVENESS OF CORRECTIVE ACTIONS TAKEN. THERE IS A NEED FOR DEVICES WHICH PROVIDE A CONTINUOUS HISTORY OF PARTICLE DENSITY, AND/OR COUNT, IN ORDER TO ESTABLISH CAUSE AND EFFECT RELATIONSHIPS. THE PURPOSE OF THE PROPOSED EFFORT IS TO (1) DETERMINE THE TECHNICAL REQUIREMENTS FOR SUCH AN INSTRUMENT(S) AND (2) DESIGN, BUILD, AND TEST ONE OR MORE PROTOTYPES. THESE DEVICES WOULD THEN BECOME THE BASIS FOR PHASE II FOLLOW ON EFFORT. THE WORK WILL INVOLVE THE DESIGN AND TESTING OF LOW COST, PORTABLE, OPTICAL BASED INSTRUMENTS WHICH DETERMINE PARTICLE CONCENTRATIONS BY (1) ABSORPTION, OR (2) SCATTERING OF A LIGHT OR LASER BEAM. A REAL TIME ANALOG OUTPUT AND COUNT WILL BE GENERATED. THE OUTPUT WILL E USED TO CALCULATE PARTICULATE CONCENTRATION SO THAT A DIRECT COMPARISON TO PM-10 CAN BE MADE. TRIALS OF THE DEVICES WILL BE DONE UNDER CONTROLLED LABORATORY CONDITIONS AND TYPICAL FIELD CONDITIONS.