New metrology for radon at the environmental level

International audienc

PARAMETERS INFLUENCING DEVIATION OF RADON CONCENTRATION FROM ITS TYPICAL DIURNAL PATTERN IN THE WINTER AND SUMMER SEASONS

Radon (222Rn) has been used as an atmospheric tracer for studying the vertical mixing processes in the planetary boundary layer (PBL). Therefore, the time series of hourly atmospheric radon concentration obtained in Ljubljana city were analyzed along with the meteorological data and back trajectory information from December 2016 to November 2017. Radon concentration exhibited the annual cycle with a higher mean in the winter (20.7 ± 15.5 Bq m–3) and a lower mean in the summer (14.6 ± 9 Bq m–3) reflecting the PBL evolution on a seasonal timescale. Most of the time, radon showed the typical diurnal variation following its related mean seasonal level attributed to the vertical mixing processes. Among this typical pattern, deviations of atmospheric radon concentration by more than ±σ from the related seasonal mean value have been detected in 9 events (±σ Ei) in the winter and summer seasons using simple statistical analysis. The parameter persistent/nocturnal inversion has usually been the reason for  +σ Ei. While, the temporal variation of the exhalation rate, wind direction/speed and maritime air masses have been the responsible influencing parameter for –σ Ei.  Key words: atmospheric radon; continuous measurement; deviations in concentration; planetary boundary layer;  persistent inversion; air masses&nbsp

Radon progeny measurement and dose estimation in Hungarian workplaces

A preliminary study of radon concentration and air-quality parameters in Hungarian workplaces revealed that using the same dose conversion factor (7.9 nSv m3 Bq-1 h-1 recommended by ICRP) – e.g. in case of a deep mine and a medicinal bath – may considerably reduce the reliability of the estimated dose.In order to gain more information related to this dose estimation problem, it was necessary to measure radon and its short-lived progenies concentrations; the unattached fraction of radon short-lived progenies; the equilibrium factor; along with temperature and the relative humidity not only in a medicinal bath (14 days) but also in a tourist cave (7 days), in a medicinal cave (7 days), in a manganese deep mine (9 days) and in a deep geological radioactive waste depository under construction (7 days) in Hungary. With the above data obtained, new specific dose conversion factors were determined taking respiration through the nose and through the mouth into consideration. Calculating with the annual labour hours related to each workplace, the effective dose of the workers was estimated.For the radon medicinal bath, the calculated dose conversion factors, distinguished nose and mouth respiration, were lower than the recommended 7.9 nSv m3 Bq-1 h-1, respectively. For the tourist cave, the medicinal cave, the manganese deep mine and the deep geological radioactive waste depository, the dose conversion factors were higher than the recommended one causing significant differences in dose estimation.9th International Conference on High Level Environmental Radiation Areas-For Understanding Chronic Low-Dose-Rate Radiation Exposure Health Effects and Social Impacts (ICHLERA 2018

OCCUPATIONAL EXPOSURE ASSESSMENT AT A THERAPEUTIC RADON SPA FACILITY IN HUNGARY

In order to estimate occupational exposure of workers in a therapeutic radon spa facility, radon concentration in the workplace air was investigated at Markhot Ferenc Hospital, Eger, Hungary. The investigated balneotherapeutic facility and its natural hot spa water are used for treatments and rehabilitations of rheumatic patients. Radon concentration, radon decay products at a bathhouse, treatment rooms and a consultation room were continuously measured in August and September 2018. In the present study, different levels of radon concentration among the observation sites and its clear temporal variations were found, though radon concentrations in the investigated sites were below 300 Bq m−3. Regarding such radon fluctuation and low equilibrium factor level (0.1), the annual effective doses of workers are estimated to be around 0.5 mSv year−1

Radon metrology for use in climate change observation and radiation protection at the environmental level

Radon (222Rn) gas is the largest source of public exposure to naturally occurring radioactivity and the identification of radon priority areas is required by the Council Directive 2013/59/Euratom. Radon is also used as a tracer to improve atmospheric transport models and to indirectly estimate greenhouse gas (GHG) fluxes using the Radon Tracer Method (RTM). This method is based on the correlation between atmospheric concentrations of radon and GHG, together with information on the radon flux data. For radiological data, all European countries have installed networks of automatic gamma dose rate monitoring stations and report the real-time information gathered to the European Radiological Data Exchange Platform (EURDEP). So far, atmospheric radon activity concentrations and radon fluxes are not yet reported in EURDEP, nor routinely measured within the European radiological networks although these observations could help to avoid false positives results. Due to above applications, there is a need of building a metrological chain to ensure high quality radon activity concentrations and radon flux measurements. Both climate and radiation protection research communities underline the need for improved traceability in low-level atmospheric radon measurements (Khanbabaee et al., 2021). The EMPIR project 19ENV01 traceRadonThis project 19ENV01 traceRadon has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme. 19ENV01 traceRadon denotes the EMPIR project reference. is aimed towards providing the necessary measurement infrastructure and transfer standards to fulfil this need. Results of this project are particularly important for improving independent GHG emission estimates that support national reporting under the Paris Agreement on climate change and for the Council Directive 2013/59/Euratom, thus benefitting two large scientific communities. In this paper, early results, such as new activity standard developments and an overview of commercial and research radon monitors are presented and discussed. These results will feed into the traceRadon project with respect to radionuclide metrology in air and its potential for the improvement of the RTM