Remarks to history of radon activity concentration metrology

Abstract

The radon issue has been known worldwide for dozens of years. Many scientific (ICRP Publication No. 137), technical (ICRU Report No. 88), and legislative (Council Directive 2013/59/EURATOM (EU-BSS)) documents have been published in the last decade. More and more attention is being paid to precise quantification to determine the concentration and consequent effects of various pollutants on human health worldwide. The quality of measurement and the variety of measurement techniques increase the need to unify measurement procedures and metrology continuity. Countries around the world are beginning to unify metrological procedures for determining different quantities based on international recommendations and standards. Not only for these reasons, it became more actual a need for more accurate radon activity concentration measurement and radon metrology unification. This paper summarizes the main remarks and technical aspects to the historical development of radon metrology.

Outdoor radon-222 in Arctic Finland

“…The observed diurnal variation of 222 Rn content of the air is similar to that found in southern Finland, 16 Poland, 17 Germany, 23 Czech Republic 24 and China. 25 High values are encountered around the Sun rise when the vertical temperature inversion stratifies the lowermost troposphere.…”

Low-Level Radon Activity Concentration—A MetroRADON International Intercomparison

“…On the other side, after being exhaled from the ground to the atmosphere, radon is diluted within the atmospheric boundary layer. Its atmospheric concentrations are usually in the range of tens of becquerels per cubic meter [2,3]. However, the radon activity concentrations in some public accessible subterranean spaces (for example, tourist caves, speleotherapy caves or underground tours built up from former mining workplaces) could be measured in the range of hundreds becquerels per cubic meterup to tens of kilobecquerels per cubic meter.…”

Preparation of multi-purpose radon emanation sources

“…Despite decades of history of radon-in-air measurements [1], accurate and SI traceable radon activity concentration measurements in air are still part of scientific research and discussions [2,3]. It was further stimulated by the European Council's new Basic Safety Standard (BSS) [4] that for the first time also deals with low radon activity concentrations (< 300 Bq/m 3 ).…”

“…This knowledge gap initiated the Metrology for Radon Monitoring (MetroRADON) European Metrology Programme for Innovation and Research (EMPIR) project [3]. Within this project an important objective was to develop radon emanation sources and procedures for the traceable calibration of radon measurement instruments below 300 Bq/m 3 with relative uncertainty of ≤ 5% (at k = 1) [1,3]. JRC contributed to the development of novel 222 Rn (radon) and 220 Rn (thoron) radioactive reference sources traceable to primary standards with stable and known radon emanation, one of the main goals in the MetroRadon project [3].…”