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Select Frisker Type                      cpm Enter Background     cm Enter Detector Width cpm Lower Limit of Detection (LLD)   Select MDC Units dpm/100cm2 Bq/cm2              MDA/MDC Calculations for Scanning Instruments      Alpha or Beta
Gamma             cm/sec dpm/100cm2 Minimum Detectable Contamination (MDC) cm2 Enter Probe Area cpm/dpm Enter Efficiency Enter Scan Speed

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Calculates the MDA for scanning instruments (friskers) in motion.  The faster the scan, the higher the MDA.  For gamma scans, units may also be in uR/hr as well as pCi/g.  The user must first determine the efficiencies in cpm per uR/hr or cpm per pCi/g using MicroShield or similar programs and the methods spelled out in the US NUREG 1507.  Cpm per uR/hr may be achieved by comparing readings of the scan instrument to a pressurized ion chamber or other calibrated dose-rate instrument while both are exposed to a source of the site isotope of interest, at the scan distance.