Revision of Radon Dose Coefficients

Revised radon dose coefficients have been published in ICRP Publication 137 Occupational Intakes of Radionuclides Part 3. A Summary of ICRP Recommendations on Radon is available in ICRPÆDIA. Although protection against radon is primarily based on measurement and control of levels of exposure, dose estimates are required in certain situations for workers. For buildings and underground mines, a dose coefficient of 3 mSv per mJ h m -3 (approximately 10 mSv per WLM) is recommended, i.e. approximately double the value of the previously recommended value. For indoor work involving substantial physical activity, and exposures in tourist caves, the recommended dose coefficient is 6 mSv per mJ h m -3 (approximately 20 mSv per WLM). This increase in dose coefficients will result in higher assessed doses to workers exposed to radon, possibly resulting in doses approaching regulatory limits in some cases. In addition, doses from natural background exposure will increase significantly. As these figures are used in communicating to the public about radiation exposures, careful consideration will be needed on how this change will be communicated.