Progress on Standardization of Radioanalytical Methods for determination of important radionu-clides for environmental assessment and waste management in Nordic nuclear industry

The NKS-B STANDMETHOD project was launched in January 2014, aiming to standardize the radioanalytical method for the determination of important radionuclides difficult to measure in Nordic industry. The present status of radioanalysis in Nordic laboratories is reviewed and presented in this report. A review article on this topic was prepared to be published in a peer review journal, and an intercomparison exercise was implemented for determination of 63Ni and 55Fe in three types of water samples: spiked water, reactor coolant water and an acid digested filter from a nuclear reactor.

Seven labs participated in the intercomparison and reported their analytical results of 63Ni. Different analytical methods used by the labs, and the results are discussed in this report. The intercomparison results for 63Ni agree relatively well for the spiked water, but a big variation of the results was observed for the real reactor coolant water and for the digested filter sample.

This indicates that the methods used in some labs could not remove interfering nuclides to a sufficient extent. An improvement of the analytical method of some labs and a follow-up intercomparison exercise are proposed.