The rule of thumb conversion for removable contamination has been 1 mrem gamma = 1 million dpm assuming Co-60 as the major isotope does anyone have a rule of thumb for 1 mrem BETA ? I'll welcome any input Thanks, M.B. Mark Bedenbaugh RNP- Ext. 1287 Beeper - 673-6040 mark.bedenbaugh@cplc.com