For those needing portability, Rad Pro for Desktop works with Windows 8.1 tablets (just tested). Will not work with Surface tablets running Windows RT.
Select Frisker Type                      cpm Enter Background     cm Enter Detector Width cpm Lower Limit of Detection (LLD)   Select MDC Units              MDA/MDC Calculations for Scanning Instruments     
            cm/sec dpm/100cm2 Minimum Detectable Contamination (MDC) cm2 Enter Probe Area cpm/dpm Enter Efficiency Enter Scan Speed

MDC Formulas
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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.