Beyond the State of Art: New Metrology Infrastructure for Radon Measurements at the Environmental Level

Abstract

Radon gas is the largest source of public exposure to naturally occurring radioactivity. Radon activity concentration maps, based on atmospheric measurements, as well as radon flux maps can help Member States to comply with the EU Council Directive 2013/59/Euratom and, particularly, with the identification of Radon Priority Areas. Radon can also be used, as a tracer, to improve Atmospheric Transport Models and to indirectly estimate greenhouse gas (GHG) fluxes. This is important for supporting successful GHG mitigation strategies. One approach to estimate GHG fluxes on local to regional scale is the socalled Radon Tracer Method (RTM), which is based on the night-time correlation between atmospheric concentrations of radon and GHG measured at a given station together with information on the radon flux data within the station footprint. Thus, atmospheric monitoring networks are interested or are already measuring atmospheric radon activity concentrations using different techniques but a metrological chain to ensure the traceability of all these measurements was missing.Since 2020 a large consortium engaged in the project traceRadon [1] to develop the missing traceability chains to improve the respective sensor networks http://traceradon-empir.eu/ . This paper presents results in the areas: Novel 226 Ra standard sources with continuous controlled 222 Rn emanation rate, radon chambers aimed to create a reference radon atmosphere and a reference field for radon flux monitoring. The achieved results are making new calibration services far beyond the state of art possible.