HIGH SENSITIVITY ENVIRONMENTAL CONTINUOUS AIR MONITOR

This poster will illustrate the design collaboration between LANL, Canberra and a Russian collaborator (yet to be selected) to develop a high sensitivity environmental continuous air monitor capable of real time alpha air monitoring at a rate of up to 1100 LPM, approximately 20 times the capacity of standard CAMs which typically handle 50-60 LPM. By processing a larger volume of air, this new instrument can be more sensitive and hence monitor a greater geographical area than standard CAMs. In order to adapt an existing CAM design to handle larger streams of air, the combination of a commercially available preseparator with EPAdesigned inlet and a high volume virtual impactor will be used. Airborne debris particles larger than 20 microns are removed by the preseparator, which also lessens the impact of environmental factors like rain and wind. From there, the air stream passes through a virtual impactor which divides it into two air streams. Larger (aerodynamic diameter) particles, such as Pu particulates and TRU-contaminated soil between about 3 and 20 microns, are inertially directed and concentrated into a minor flow of about 56 LPM which passes through the CAM where the particles are deposited on the filter. Smaller particulates below about 3 microns including radon progeny, soot and condensation nuclei are exhausted with the major air stream, with the added benefits of reduced filter clogging and longer filter life. This new instrument could have applications in stack monitoring, safeguards, homeland defense, and environmental monitoring. Additional system features could include simultaneous alpha and beta detection, GPS, meteorological, wireless communications and automatic filter changer, all of which would enhance remote unattended monitoring applications.