How will the new dose coefficients for radon progeny affect your doses?
Radon is a naturally occurring radioactive gas, which has no smell, colour or taste. It comes from the radioactive decay of radium, which is present in small amounts in rocks and soil. As a gas, radon can easily escape from the ground into the air where it can be inhaled.
The inhalation of radon and its progeny is recognised as a cause of lung cancer. However tobacco smoking is the main cause of lung cancer both globally and in Australia.
The International Commission on Radiological Protection (ICRP) have re-evaluated how they estimate lung cancer risk for exposure to radon progeny and doubled its estimate of risk from exposure.
Following the ICRP’s re-evaluation, we have published an advisory note on the new dose coefficients for radon progeny to guide you through what has changed.
Studies carried out in Australia indicate that doses assessed from inhalation of radon progeny for workers in the uranium mining industry and in show caves will increase by a factor of two or more from current assessments with the new dose coefficients. These studies indicate that the default values of new ICRP dose coefficients would be suitable for regulatory and radiation protection purposes in Australian underground mines and show caves.
Surveys have shown that radon levels in Australian homes are low. The overall risk for lung cancer from radon in the Australian population is very small. However, there is evidence that smoking leads to a strong enhancement of the radon-related lung cancer risk. The best way of reducing the total lung cancer risk, as well as the lung cancer risk from exposure to radon, is to avoid tobacco smoking.
In 2017, we published the Guide for Radiation Protection in Existing Exposure Situations which includes guidance for managing exposure to radon in homes and workplaces.