BRE BR413 PDF

Radon is a colourless and odourless radioactive gas formed where uranium and radium are present. It can occur in any area of the country, but certain regions, partly related to the underlying geology, will experience higher concentrations. Radon seeps up through cracks and fissures in the soil and in open areas is naturally dispersed into the atmosphere. Any solid enclosure in these locations can inhibit this free dispersion of the gas and consequently there is a danger of high concentrations of radon developing within buildings. Such concentrations may constitute a risk to health.

Breathing in radon gas increases the chances of developing lung cancer and since many people spend a high proportion of their time at home, concentration levels in dwellings are very important. This report focuses on new dwellings, extensions to existing buildings and the constructional features that affect this risk. Although the risk is relatively insignificant for people visiting or living for short periods in a dwelling with high levels of radon, long-term exposure can increase the risk to the point where preventative action is recommended.

Radon originating in the subsoil is transported up into the dwelling by air movement. In traditional construction there are a number of paths through which the gas can be carried into the living areas.

This report provides guidance on protective measures in new dwellings and extensions to existing buildings. Practical measures are outlined which, when applied to new dwellings, will significantly reduce the ingress of radon. Guidance is provided for both solid and suspended floors. The gas must be dealt with before it becomes a risk to health and therefore the measures are generally applied at or below the lowest floor level.

The initial research on floors was undertaken in some of the worst affected areas in the UK. The floors of the properties on which monitoring could be carried out were mainly concrete. The recommendations for concrete floors, which are contained in this report, have been based on that work (BRE Report Radon: guidance on protective measures for new dwellings ).

Methods for dealing with suspended timber floors are the subject of a current research programme. The results of that work were not available for inclusion within this report. The details for timber floors are therefore provided as best practice advice in terms of current knowledge. These recommendations may be modified as more information becomes available. Protection from radon at work is specified in the Ionising Radiations

Regulations (Northern Ireland) 1985^[1], legislation made under the Health and Safety at Work (Northern Ireland) Order^[2] administered by the Health and Safety Inspectorate. The technical advice contained in the present report may however, be of use to designers and builders of new structures whose form of construction and compartmentation is similar to housing and where the heating and ventilation regime is similar to that used in housing. This is likely to include small office buildings and some primary schools. Further information is contained in the HSE/BRE Report Radon in the workplace.