Proficiency in Determining 134Cs and 137Cs in Aquatic Samples Using Gamma Spectrometry.

Participation in proficiency tests is an essential part of quality assurance activities for any laboratory involved in radiation metrology. Radioanalytical laboratory, Health Physics Division, BARC, regularly participates in national and international proficiency tests to demonstrate its radiometric capabilities for estimation of low-level natural and anthropogenic radionuclides in environmental matrices. The laboratory has been participating in annual IAEA Proficiency Tests conducted by Terrestrial Environmental Laboratory (TEL), IAEA, for estimation of natural radionuclides as well as fission and activation products in natural and spiked samples. This paper presents the results of estimation of ¹³⁴Cs and ¹³⁷Cs (two most important anthropogenic radionuclides that may be released from nuclear reactors during accident conditions) in spiked water samples in last five years of IAEA Proficiency Tests during 2018–2022. All results were lying well within 1σ level of the target values indicating the excellent analytical capability of this laboratory for analysis of ¹³⁴Cs and ¹³⁷Cs in aquatic environment. [ABSTRACT FROM AUTHOR]