The UK Radon Programme: a review of the response to the discovery of elevated levels in the built environment

Radon is a naturally occurring, radioactive gas that is a member of Group 0 of the periodic table. It is formed by the radioactive decay, in soil, of radium. Normally, it is found in extremely low levels in the atmosphere but in certain geological formations it can be a significant component of soil gas and hence levels of radon gas in mines can be extremely high. Doses from radon are the largest component of the average radiation exposure for the UK population. Certain areas of the UK have been found to have elevated levels of radon in dwellings and these are classified as Affected Areas. In Affected Areas, individuals, in homes and the workplace, can be receiving high doses of radiation. There is overwhelming evidence that exposure to elevated levels of radon in mines leads to lung cancer, and recently a number of reports have been published that confirm it to be a serious health risk at the levels found in some domestic dwellings. Primary academic journals testify to the extensive scientific research on radon this century, including its environmental occurrence. Despite evidence to the contrary, it was considered that radon was not a serious risk to public health as it was found in such low levels in the atmosphere. It was discovered, during the 1970s, that radon can concentrate in the built environment and reach levels never before considered feasible. Radon programmes commenced in a number of countries in an attempt to determine the extent of the problem and to suggest remediation strategies. The UK programme has offered advice on domestic and industrial buildings in an attempt to encourage all concerned to reduce radon levels. Despite the apparent success in the identification of Affected Areas the programme has not yet been able, due to resource constraint, to convince large enough numbers of the public to remediate.