- What is radon?back to top
Radon is a naturally occurring radioactive gas. It is invisible, odourless and tasteless, and can only be detected using special equipment.
- Where does it come from?back to top
Radon comes from the radioactive decay of uranium, which is present in small quantities in all rocks and soils. Because it is a gas, it can move freely through the ground enabling it to enter the atmosphere or seep into buildings.
- What is the health risk associated with radon?back to top
Radon is a carcinogen, in the same group as tobacco smoke and asbestos.
Long-term exposure to high levels of radon can irradiate lung tissue and increase the risk of lung cancer.
- How serious is the risk? back to top
The magnitude of the risk depends on the quantity of radon inhaled and the length of exposure. Smokers exposed to high levels of radon are at greater risk from lung cancer than non-smokers. Radon-linked lung cancer accounts for 150-200 deaths each year in Ireland.
- Does radon cause any other illnesses?back to top
There is no current scientific evidence linking radon exposure with other forms of cancer, or other respiratory illnesses.
- How does radon enter workplaces?back to top
Radon comes from the ground and gets into buildings mainly through cracks in floors or gaps around pipes or cables. As the pressure inside a building is slightly lower than the pressure outdoors, radon will be drawn from the ground into the building. This phenomenon is known as pressure-driven flow.
- Which workplaces are at risk?back to top
All workplaces can be at risk from radon. Workplaces at higher risk tend to be those located in High Radon Areas. Underground workplaces such as mines and show caves are also at higher risk of increased radon levels, wherever their location might be.
- What is a High Radon Area?back to top
A High Radon Area is an area in which the RPII has predicted that 10 per cent or more of the buildings are likely to have radon levels above the acceptable level.
- Where are the High Radon Areas in Ireland?back to top
The RPII has produced radon maps and statistics for each county. Research has revealed that almost one third of Ireland is affected by high radon levels, with the South East and the West being of particular concern. However, high radon levels can exist in every part of the country.
- Why are some areas more affected than others? back to top
The distribution of radon is largely determined by the geology. Certain types of rock and deposits - including some granites, limestone and shales – tend to be associated with high radon emissions, for various and different reasons.
- Are workplaces outside High Radon Areas at risk?back to top
Harmful levels of radon can affect indoor buildings everywhere, including those which are not located in High Radon Areas. Large variations in radon emissions can occur even within small geographical pockets.
- Are outdoor workplaces affected by radon?back to top
Radon which is dispersed into the open air is generally diluted to harmless concentrations. If you work in outdoor construction, fishing, agriculture, transport, or in any other non-enclosed workplace, you are unlikely to be affected by radon.
- Can radon affect upper floors? back to top
Because radon enters a building from the ground, the worst affected workspaces are likely to be at basement and ground floor levels, with a diminishing concentration the higher you ascend. Radon testing is normally conducted as near to the ground level as possible. If radon concentrations at ground floor level are within acceptable limits, upper floors of the same building should also be safe.
- What if I suspect my workplace may be affected by radon?back to top
If you are an employer, you should have the radon levels measured in your workplace by an approved measurement service. If you are a worker, you should raise your concerns with your employer and/or trade union.
- How do I test for radon?back to top
Radon measurement must be undertaken by an approved measurement service. Radon concentrations are measured at basement and ground floor levels of workplaces, in locations that are occupied by workers for more than 100 hours a year (i.e. workshops and offices, as opposed to corridors and washrooms).
- What are considered to be safe levels of radon?back to top
Irish legislation sets a national Reference Level of 400 becquerel per cubic metre (Bq/m3) in workplaces, measured over a consecutive three-month period.
- Can high radon levels be reduced?back to top
Harmful radon concentrations can be reduced to safe levels by carrying out remedial work on the affected building. This might include measures such as improving the ventilation or installing an extraction system (radon sumps).
- At what radon concentration should remedial work be undertaken? back to top
The RPII recommends remediating all workplaces which have a radon measurement above the national Reference Level of 400 Bq/m3.