Development of Am-241 Activity Standards

The identification and monitoring of long-lived alpha-emitting radiotoxic radionuclide in nuclear waste management, environmental monitoring and internal dosimetry are crucial as far as the safety of individual, community and environment is concerned. This requires sample preparation techniques with thin, uniform and adherent deposition of actinides on the substrate for carrying accurate and high-resolution alpha-spectrometric measurements. Electrodeposition is one such technique. Standard sources prepared using this method can be used for calibration of detectors for alpha measurements. In this paper, we discuss the methodology adopted for electroplating Am-241 sources and subsequently carrying the standardization of electroplated sources with 2π-Proportional counter (PC). Efficiency of Am-241 electroplated source in 2πPC was determined to be 49%. The sources were further investigated for alpha-spectrometric measurements leading to the generation of high-resolution spectra exhibiting a full-width at half-maximum (FWHM) value of 38 keV. Scanning electron microscopy (SEM) for surface morphological studies yielded non-clustered deposition, indicating the even distribution of radionuclide and consequently, homogeneity. A tissue wipe test was performed to evaluate the adhesion of radionuclide on substrate. The present study reveals the absence of counts on wiped tissue indicating adherency in deposition.