Standardization of( 59)Fe by efficiency extrapolation 4 pi beta-gamma anticoincidence method

A solution of Fe-59 was standardized in the frame of a Bureau International des Poids et Mesures (BIPM) international key-comparison piloted by Asian Pacific Metrology Program (APMP) regional metrology organization. The method used was the live-timed 4 pi beta-gamma anticoincidence counting with extended dead-time with efficiency extrapolation method. The confirmation of these results was performed by conventional 4 pi beta-gamma coincidence counting with efficiency extrapolation and CIEMAT/NIST liquid scintillation counting methods. The value of the evaluated anticoincidence measurement was used to calibrate the LNMRI second standard ionization chambers for providing Fe-59 solutions to nuclear medicine canters in the procedures of anaemia diagnosis. Besides this value was adopted as the comparison value of LNMRI and sent to APMP organization. The half-life of Fe-59 was determined following the decay of one ampoule sample with Fe-59 solution in an ionization chamber (Centronic model IG12).