Intercomparison of Radon Flux Monitors at Low and at High Radium Content Areas under Field Conditions

Abstract

Interlaboratory exercises are a good tool to compare the response of different systems to the same quantity and to identify possible inconsistencies between them. One of the main goals of the EMPIR 19ENV01 traceRadon project is to harmonize radon flux measurements based on different systems and methodologies. In the framework of the traceRadon Project, two radon flux intercomparison campaigns were carried out in October 2021 at high and at low radon source areas. Four institutions participated in the field intercomparison exercises with their own systems. Every system was based on a specific radon monitor (diffusion or pump mode) and an accumulation chamber (with manual or automatic opening). Radon fluxes were calculated by each participant using both exponential and linear fittings of the radon activity concentration measured over time within the accumulation chambers. The results of this study show mainly: (i) the exponential approach is not advisable due to the variability of the radon flux and the leakage of the systems during long-time measurements; (ii) the linear approach should be applied to minimize the measurement period in agreement with the time response and sensitivity of the monitors; (iii) radon flux measured at high radon source areas (radium content of about 800 Bq kg−1) risks being underestimated because of the influence of advective effects; (iv) radon flux measured at low radon source areas (radium content of about 30 Bq kg−1) may present large uncertainties if sensitive radon monitors with pump mode are not used.

A Case Study of the Radon Hazard at the Boundary of a Coal Minefield

“…This finding suggests that an increase in radon concentration in soil does not necessarily result in an increase in RFD, but it increases the chance of encountering high values. Similar results were previously obtained in loose rocks of a similar composition [68,69]. It is known that the relationship between RFD and soil radon decreases as depth increases.…”

Radon Hazard of the Zhurinsky Fault for the Population in the Kuznetsk Coal Basin: Primary Results

“…We did not find a relationship between soil VAR and RFD. Similar results have been obtained before [59]. For a similar area with loess-like loams, the authors also noted significant differences in RFD and soil radon [60].…”

Investigation of the Performance of Various Low-Cost Radon Monitors under Variable Environmental Conditions

“…The comparison of radon monitors was carried out at the Laboratory of Natural Radiation (LNR) (see Figure 1 ), located at the former uranium mine managed by ENUSA Industrias Avanzadas (Saelices el Chico, Salamanca, Spain) [ 8 ]. This facility has been used since 2000 to carry out several intercomparison exercises and in situ calibrations, addressing the measurement of radon concentration in indoor air, radon exhalation rate from soil, radon concentration in soil, and external gamma radiation dose rate under environmental conditions [ 9 , 10 , 11 , 12 ]. The suitability of this environment for such activities is attributed to the high content of radioactive elements present in the soil, together with the site-specific environmental conditions.…”