Building Surveyor Blog

What is Radon?
Radon is a naturally occurring radioactive gas, which produces tiny radioactive particles. It originates from the decay of uranium, which is present in small quantities in all rocks and soils. It is colourless, odourless and tasteless and can only be measured using special equipment.

Because it is a gas, radon can move freely through the soil enabling it to enter the atmosphere. When radon reaches the surface and out into the open air, it is diluted to harmless concentrations, but when it enters an enclosed space, such as dwelling, it can accumulate to unacceptable high concentrations.

How does it enter a building?
Radon can enter a building from the ground through small cracks in floors and through gaps around pipes or cables. Radon tends to be sucked from the ground into a building because the indoor air pressure is usually slightly lower than outdoors. This pressure difference occurs because warm indoor air is less dense than outdoor air.

What are the Health Effects?
Radioactive gas when inhaled, are deposited in the airways and on the tissue of the lung.  This results in a radiation dose that can cause lung cancer. The risk of contracting lung cancer from exposure to radon depends on how much radon you have been exposed to and for how long. Radon is the second leading cause of lung cancer after smoking.

How can I tell if I have Radon in my dwelling?
The two most common devices used for measuring indoor radon concentrations are the “alpha track detector” and the “charcoal canister”. The charcoal canister is a small container of activated carbon, which absorbs radon. It is exposed in a living area for about a week and then sent to a laboratory for analysis.

The alpha track detector gives a more accurate reading of the average exposure but must be left in place for a longer period, usually three months, to cover the widely fluctuating daily and seasonal variations. The detector consists of a small container, which allows the alpha particles released by the radon to come in contact inside the container with a small piece of a special plastic in which tracks are formed by the radiation striking it. After exposure for the recommended time it is also sent to a laboratory for analysis.

These tests can be carried out by Radiological Protection Institute of Ireland.

What has the Irish Government done to help solve the problem?
The Department of Environment, Heritage and Local Government have published a Technical Guidance Document (TGD) Part C of the Building Regulations outlining certain protection measures to be carried out during the construction of new buildings. A typical example of protection is the provision of a sealed radon membrane and a means of extracting radon from substructure such as a sump with connecting pipe work, which is ventilated to the outside air.

What if I live in an old dwelling?
There are a number of remedial works that can be undertaken to reduce radon levels, these include:

•   Sealing floors and walls
•   Increasing indoor ventilation
•   Increasing under-floor ventilation
•   Positive pressurisation
•   The radon sump (sub-floor depressurisation)

How do I know if I live in a high-risk area?
Radiological Protection Institute of Ireland (RPII) have completed a national survey of radon levels in Ireland, which has identified high radon areas. These areas have been identified on a map of Ireland and can be seen on www.rpii.ie/radon.

For further information refer to the Radiological Protection Institute of Ireland on www.rpii.ie of The Department of Environment, Heritage and Local Government on www.environ.ie.