Detection of BW Agents: Dugway Trinational BW Field Trial 20-30 October 1993,Dugway, Utah. Mobile Aerosol Sampling Unit Data Analysis

摘要

An aerosol of BW simulant (BG spores) was generated by Micronair disseminators asa point source at 800 m from sampling systems. Propylene gas was also disseminated concurrently as a tracer. Collection and measurement of aerosol were perform by Mobile Aerosol Sampling Unit (MASU) consisting of an Aerodynamic Particle Sizer particle sizer and a dichotomous sampler. Environmental data (wind speed and direction among others) were also logged to assist analysis of cloud dynamics. Information gathered the APS served to reveal the presence of unusual aerosol. By careful inspection of the data, it was anticipated that alarming algorithms could be developed. Samples collected by the DS provided important microbiological information like cell viability, a definitive indicator for the presence of biological aerosol. Data from day 271, trial 3, were chosen to illustrate the capability of the MASU in defining aerosol characteristics. In this trial, the primary cloud passage was followed immediately by a second, both revealed by analysis of the data generated by the sampling system. This phenomenon was clearly shown by detection of two propylene concentration peaks within the 30 min trial period. Total particle count data from the APS also revealed two similar peaks at the same time period. Aerosol mass information was obtained by transforming particle size and number data. A time plot of these mass numbers also revealed corresponding agreement with the propylene tracer. Similarly, viable spore data also fell in line with these observations. From this experiment, it is shown that the APS was capable of detecting the presence of about 1 x 10(sub 3) viable spores per litre aerosol.