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Radon Gas

Some homes and workplaces within Devon are known to be affected by high levels of Radon gas, primarily due to the geology of the area. We can provide advice on radon however the following questions and answers may give you the information you need.

What is radon?
Radon is a gas that has no colour, odour or taste and comes from the natural radioactive breakdown of uranium in the ground.

You can be exposed to radon by two main sources:
Radon in the air.
Radon in drinking water.

Radon can get into the air you breathe and into the water you drink. Radon is also found in small quantities in outdoor air.

Most of the radon in indoor air comes from soil underneath properties. As uranium breaks down, radon gas forms and seeps into the ground. Radon from soil can get into any type of building – homes, workplaces and schools and build up to high levels in the air inside the building.

Radon gas can also dissolve and accumulate in water from underground sources (called ground water), such as wells, springs or boreholes. When water that contains radon is used for showering, washing dishes and cooking, radon gas escapes from the water and goes into the air. It is similar to carbonated soda drinks where carbon dioxide is dissolved in the drink and is released when you open the bottle. Some radon also stays in the water.

Radon is not a concern in water that comes from lakes, rivers and reservoirs (called surface water), because the radon is released into the air before it ever arrives at your tap.

Why is radon a health concern?
Breathing radon in indoor air can cause lung cancer. Radon gas decays into radioactive particles that can get trapped in your lungs as you breathe. As these break down further, the particles release small bursts of energy. This can damage lung tissue and increase your chances of developing lung cancer over the course of your lifetime. People who smoke have an even greater risk. Not everyone exposed to high levels of radon will develop lung cancer. However, radon in indoor air is the second leading cause of lung cancer. About 2,500 deaths a year in the United Kingdom are caused by breathing radon in indoor air.

Only about 1 to 2% of radon in the air comes from drinking water. However, breathing radon released to air from tap water increases the risk of lung cancer over the course of your lifetime. Some radon stays in the water; drinking water containing radon also presents a risk of developing internal organ cancers, primarily stomach cancer. However, this risk is smaller than the risk of developing lung cancer from radon released to air from tap water.

Is there radon in my drinking water?
Not all drinking water contains radon. If your drinking water comes from a surface water source such as a river, lake or reservoir, most radon that might be in the water will be released into the air before reaching your water supplier or property. Radon is only a concern if your drinking water comes from underground, though not all water from underground sources contains radon.

I receive water from South West Water. Is there a problem?
There is no problem with radon in mains water supplied by South West Water. Nearly all South West Water’s water sources are upland surface water catchments and the few underground sources in use are regularly checked. No radon enters the mains distribution system.

What levels of radon in indoor air should I be concerned about?
The Government’s recommended action level for radon in air in domestic houses is 200 becquerels per cubic metre. This is the level at which it is suggested you ought to take some remediation action.

In workplaces, employers have a duty to comply with the Ionising Radiation Regulations 1999 and here the compliance level is compulsory and fixed at 400 becquerels per cubic metre

What levels of radon in drinking water should I be concerned about?
The European Union is considering a draft recommendation of the protection of the public against exposure to radon in water supplies. Because the way in which radon irradiates the body is quite different when it is swallowed in water than if it is inhaled in air, the action level for radon in water is not the same as for radon in air. The risk to a typical person drinking water with radon at this concentration is similar to the risk which would arise from breathing air which contained radon at the action level in homes of 200 becquerels per cubic metre.

The European Union draft recommendation is:

  * For private water supplies that are part of a commercial or public activity (eg hotels or bed & breakfast) remedial action should always be taken when the radon concentration exceeds an action level of 1,000 becquerels per litre.
   * For individual water supplies (no commercial or public activity) consideration should be given to taking remedial action when the radon concentration exceeds an action level of 1,000 becquerels per litre.

These levels have been adopted locally in the South West to deal with radon levels in water in West Devon.

How do I test for radon?
You can contact the Health Protection Agency, who offer a home radon testing kit.

How do I test for radon in water?
If you get your water from South West Water, there is no need for a test to be carried out – the water will be free of radon.

If your water comes from a private surface water source, most radon that may be in the water will be released to the air before it makes its way to your tap and there is no need to test for radon. If your private water supply source comes from a ground water source, ie a borehole, well or spring, then you may need to have your supply tested

Private water supplies that are in high risk areas and are part of a commercial or public activity will automatically have their water supplies tested for radon as part of the Council’s normal sampling programme, for which a charge will be made.

How do I remove radon from the air in my home?
There are a number of ways of reducing radon in air, most of them simple and relatively inexpensive. The short guide " Radon – a Guide to Reducing Levels in your Home (603KB - 22 August 2011 - PDF Help)" can give you more information.

How do I treat radon in drinking water?
If you have high levels of radon in your privately supplied drinking water there are a number of things you can do. The most effective treatment is to remove radon from the water before it enters your home. This is called point of entry treatment. There are two types of point of entry devices that remove radon from water.
  * Granular activated carbon (gac) filters which use activated carbon to remove the radon and;
   * aeration devices which bubble air through the water and carry radon gas out into the atmosphere through an exhaust.
GAC filters tend to cost less than aeration devices, however, radioactivity collects on the filter which may cause a handling hazard and require special disposal methods for the filter.

Further information

Buildings Research Establishment Ltd (BRE)
Garston, Watford, WD2 7JR.
BRE can provide advice on radon in the workplace, dwellings with cellars and basements, major alterations and conversions and various methods of radon remediation.

Health Protection Agency (HPA)
Chilton, Didcot, Oxon, OX11 0RQ.
The HPA can provide a range of information relating to occupational exposure to radon.

The Radon Council
PO Box 39, Shepperton, Middlesex TW17 8AD.
The Radon Council has a list of organisations that provide radon remediation and removal services.

Page last updated on 24 May 2012