Radon levels lower

Last month the Sentinel reported how almost 500 homes in the Derry City Council area may exceed the recommended action level for the lung cancer-inducing radioactive gas.

A report by the local authority's Chief Environmental Health Officer then noted that a NIEA report published in November indicated that between 250 and 460 houses in Londonderry were estimated to be above the Radon Action Level (200Bqm-3).

But in a report to tomorrow’s Environmental Services committee the head of Building Control states that radon levels have significantly reduced in Londonderry over the past decade.

The report notes that maps of radon-affected areas compiled in 1999 were built into the Building Regulations (NI) 2000.

But it goes on to argue that an updated map shows radon levels have reduced here and that special protection installations are not necessary on all new dwellings.

The report states: “The Northern Ireland Environment Agency (NIEA), in association with the Radiation Protection Division of HPA, has now published an updated report on radon-affected areas.

“This follows more detailed measurements of radon levels in dwellings throughout the Province. This report contains updated maps showing the radon-affected zones in each District Council area. These latest maps indicate that radon levels in the Derry City Council area are not as high as shown in the 1999 report.

“Substantial parts of the District that were previously shown as radon-affected areas are no longer shown in this way. This means that it is not necessary to install special radon-protection measures in dwellings to be built in these areas.”

It continues: “The difficulty for us in Building Control is that the radon-affected areas as shown in the 1999 maps were made part of the Building Regulations (NI) 2000 and requirements for radon protection were specially imposed for new dwellings to be built in these areas.

“However, the latest maps indicate that there is no need for these requirements in many areas, now including most of the West Bank. It is therefore illogical for us in Building Control to impose radon-protection measures if they are not needed.”

The Council’s Environmental Services committee may decide tomorrow whether to allow Building control to relax the regulations of 2000 for dwellings not identified as a radon-affected zone in the 2009 map.

Radon is a naturally occurring radioactive gas that is generated in some types of porous rocks and soil. It has been estimated that around 30 deaths a year from lung cancer attributable to exposure to radon occur in Northern Ireland (out of a total of around 850 deaths from lung cancer).