Testing of thoron cross-interference of continuous radon measuring instruments

  • Tuukka Turtiainen STUK—Radiation and Nuclear Safety Authority, Helsinki, Finland
  • Krasimir Mitev Sofia University “St. Klimet Ohridski”, James Bourchier Blvd, Sofia, Bulgaria
  • Rohafza Dehqanzada STUK—Radiation and Nuclear Safety Authority, Helsinki, Finland
  • Olli Holmgren STUK—Radiation and Nuclear Safety Authority, Helsinki, Finland
  • Strahil Georgiev Sofia University “St. Klimet Ohridski”, James Bourchier Blvd, Sofia, Bulgaria
Keywords: thoron, cross-interference, radon, radon measuring instrument


Thoron (220Rn) may interfere with radon (222Rn) measurements, if present. We measured the thoron cross-interference (CI) signal of nine types of electronic radon instruments in constant thoron concentration without the presence of radon. The CI signal increases for the first 3 days of the exposure. Also, the initial interference signal may vary between instruments. Therefore, we propose a new test method for quantifying the thoron CI in radon measuring instruments. This includes exposure of the instrument in constant thoron concentration for a minimum of 3 days and fitting the acquired data in a simplified function, which will provide two parameters: initial and final CI.


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How to Cite
Turtiainen T., Mitev K., Dehqanzada R., Holmgren O., & Georgiev S. (2022). Testing of thoron cross-interference of continuous radon measuring instruments. Journal of the European Radon Association, 3. https://doi.org/10.35815/radon.v3.7694
Special issue - European Radon Week 2020