- The 1997 Building Regulations require that "Precautions shall be taken to avoid danger to health and safety caused by substances (including contaminants) found or in the ground to be covered by the building".
In this Part - "Includes any substances which is or could become flammable, explosive, corrosive, toxic or radioactive and any deposits of faecal or animal matter"
Radon is deemed to be a contaminant that is a danger to health and therefore comes under the terms of this requirement and is referred to in Technical Guidance Document C.
- A "High Radon Area" is an area where the RPII National Survey indicates that more than 10% of houses are likely to have a Radon level exceeding the National Reference Level.
- New House in a High Radon Area: Foundations must incorporate measures to protect the building from Radon in the ground e.g. a sealed membrane of low permeability and a potential means of extracting Radon from the sub-structure, such as a passive sump with an outlet.
- New House ouside High Radon Area: Foundations must incorporate a means of extracting Radon from the sub-structure i.e. a Radon Sump.
- The passive sump can be activated by the installation of a fan if Post-Construction Survey of a particular house indicates that actual Radon Gas level exceeds the National Reference Limit of 200 bequerels per cubic metre (200Bq/m3 )
