New beta primary standard (BPS2) and revised ISO 6980 at PTB

Abstract

In this work, firstly, the main characteristics of PTB’s new beta primary standard (BPS2) are presented in comparison to its previous one (BPS1), i.e. to the Böhm chamber. Secondly, the main changes of the revised ISO standard series on beta reference radiation fields, ISO 6980, are described. Finally, the application of the revised ISO 6980 to both PTB’s new and old beta primary standard is implemented. It turns out that both devices, BPS2 and BPS1, agree on average to about ± 1 % with each other, i.e. well within their one sigma statistical uncertainties of approximately 3 % for 147Pm and 1.5 % to 1.8 % for 85Kr, 90Sr/90Y and 106Ru/106Rh radiation qualities. Therefore, as of mid-2023, PTB moved from the 2004–2006 version of ISO 6980 to the revised version from 2022 and from the old beta primary standard, BPS1 (i.e. the Böhm chamber) to the new one, BPS2.