A PORTABLE SWIPE MONITOR FOR ALPHA-CONTAMINATION

A portable swipe monitor has been developed at Los Alamos National Lab oratory for the state of New Mexico. The monitor is intended for use a t New Mexico ports of entry to detect removable alpha contamination on shipments bound for the proposed Waste Isolation Pilot Plant (WIPP). This detector uses Long-Range Alpha Detection (LRAD) technology, which monitors ionization created by alpha interactions with ambient air, a nd includes built-in background subtraction of external radiation fiel ds and radon. Its sensitivity to alpha contamination is on the order o f a few tens of dpm, and it has excellent linearity throughout its ent ire range of over 200,000 counts per minute of alpha activity. Designe d to be used primarily in the field, the monitor is battery-powered an d can operate continuously for up to five hours.