The paper presents the first major analysis of the costs and benefits of radon remediation programmes in both existing and new domestic properties in areas affected by radon in the UK. The study was conducted in Northamptonshire, where over 6% of houses are above the UK domestic Action Level of 200 Bq.m 3 , and where new houses in parts of the county, where over 10% of houses are above the Action Level, have been fitted with a radon-proof membrane and provision of a sump, but without a fan. The county also contains areas where 3-10% of houses are over the Action Level, where, until January 2000, only the provision of a sump without a fan was required.
Remediation programmes in existing domestic properties, and in new houses in areas with over 10% of houses above the Action Level, can be justified in terms of costs per cancers averted when compared with other health interventions. A modest reduction in lung cancer induction can be predicted, particularly in areas where significant numbers of new houses are being built.
However, where UK programmes rely on householder actions, such as remediation of existing houses, they have had limited success-with a large majority of householders taking no action at all. As many countries have regions where domestic properties have raised radon levels, this analysis is generally applicable to many developed European countries. Policy-makers in such areas need to design more inventive public health campaigns, or develop legal or financial incentives, so that the uptake of remediation is stimulated.