Radon FAQs

Yes. Radon levels in homes vary during the day, from one day to the next, and from winter to summer, mainly because of temperature differences between indoors and outdoors. They are generally higher at night and during the winter.
Issue 3 (Summer 1995) (PDF, 1.3 MB)

No. Although radon enters homes all the time, some is carried away by the natural ventilation. Even in a home with good draughtproofing and double glazing, the air changes several times a day.

The main danger from high radon exposure is the increased risk of lung cancer. If there is any risk of leukaemia, it is, by comparison, extremely small.
Issue 32 (Autumn 2002) (PDF, 398 KB)

There is no indication from current evidence that the risk to children is any greater than that for adults.
Issue 32 (Autumn 2002) (PDF, 398 KB)

Most people receive a larger radiation dose from radon indoors than from any other source, whether from the many industrial uses of radiation, nuclear power or medical exposures.

Average annual dose of ionising radiation to the UK population from all sources, 2.7mSv:

Yes. Most water supplies have low levels of radon, but some smaller supplies may have high levels. None has been found in the UK with high enough levels to cause as much concern as radon from the ground. The Health Protection Agency endorses a proposed European guideline suggesting action if radon levels in private water supplies exceed 1000 becquerels per litre.
Issue 9 (Winter 1996) (PDF, 200 KB)

The risk from radon is calculated for a lifetime spent in the same home; the risk from holiday periods will be very small.

No. Exposure from the natural radioactivity in food is much less than from radon in the home.

No. Radon is present in all parts of the UK, but in the most populous areas the levels are quite low. Some of the highest levels have been found in the southwest, but levels well above average have been found in some other parts of England and parts of Scotland, Wales and Northern Ireland. However, even in these areas most homes have low levels.
The Indicative Atlas of Radon in England and Wales summarises the areas with higher risks of finding high radon levels
Issue 30 (Spring 2002) (PDF, 357 KB)

No. There are extensive areas outside southwest England where high radon levels occur in buildings, including large parts of Wales and the Midlands, and some more northerly areas (see our radon map).
The Indicative Atlas of Radon in England and Wales (HPA-RPD-033) summarises the areas with higher risks of finding high radon levels
Issue 30 (Spring 2002) (PDF, 357 KB)

All homes have radon in the air to a greater or lesser extent. The main source of radon in homes is the ground beneath the home. Radon cannot escape from the inside of solid granite, only from a very thin surface layer. For this reason, granite walls, fireplaces and worktops add very little to indoor radon concentrations.
Issue 32 (Autumn 2002) (PDF, 398 KB)

Yes. All countries are affected to some degree by radon, but the problem is receiving particular attention in Sweden, the other Nordic countries, Germany and the USA.
Issue 6 (Spring 1996) (PDF, 115 KB)

No. Radon from rocks and soil in the open disperses rapidly in the air.
Issue 14 (Spring 1998) (PDF, 367 KB)

Even in Affected Areas most homes have low levels of radon, and high levels can generally be reduced at fairly moderate cost. Concern about radon should not therefore influence your choice of home. Further advice is given in the information pack that is available free of charge from the HPA. Once you have moved, you can obtain a measurement for around £40 (see below). The test is confidential, the significance of the result is explained and advice is provided on how to reduce high levels.

The Indicative Atlas of Radon in England and Wales (HPA-RPD-033) summarises the areas with higher risks of finding high radon levels; a specific report for an individual property can be obtained for a small fee through the UKradon.org website [outside link].

Issue 34 (Spring 2003) (PDF, 113 KB)

The report will indicate whether or not the property concerned is in a Radon Affected Area. The only way to find out if a particular house has a high radon level is to test, so the vendor should be asked if a result is available. Otherwise, your solicitor should be asked to arrange retention of a sum to cover radon mitigation work should a subsequent test show it to be necessary.
Issue 22 (Spring 2000) (PDF, 112 KB)

One of the solicitors retains a sum from the sale proceeds pending the result of a radon test by the new occupier. If this result is below the Action Level, the money is returned to the vendor, normally within six months. If this test result exceeds the Action Level, the money is used to pay for mitigation work. Once this work has been completed and shown to be effective by a further test, up to a further nine months after the first test result, any surplus is returned to the vendor. For most properties a sum of around £1000 is adequate for normal mitigation work and HPA advises that the most effective method of mitigation should always be used.
Issue 15 (Summer 1998) (PDF, 270 KB)

Yes, but the radon level may change when the home is occupied. Homes undergoing alteration also cannot be measured accurately; it is best to wait until building work is complete and the home is again occupied in a normal manner.

Access the radon measurement service page on this website.
Issue 26 (Spring 2001) (PDF, 186 KB)

Radon levels vary so much that it is not possible to predict with any certainty the long-term values from short-term measurements.
Issue 29 (Winter 2001) (PDF, 150 KB)

Because radon levels in houses vary over short periods with changing weather conditions, such measurements may give a misleading estimate of the annual average radon concentration. They can be used for screening purposes, although a further measurement may be required in some cases.
Issue 15 (Summer 1998) (PDF, 270 KB)

No. Smoke detectors contain a small amount of a radioactive material, which does not emit radon and will not affect measurements in your home.

Geiger-counters are unable to detect radiation from radon and its decay products at the levels found in homes.

Yes. When you receive the result of radon test from the Health Protection Agency you will be advised whether you need to take steps to reduce the level. If you do, you will be sent a copy of a Government booklet, "Radon: A guide to reducing levels in your home" which gives details of the various methods. The booklet also contains useful addresses for further information. The Environmental Health Department of your local council can also offer advice.
Issue 24 (Autumn 2000) (PDF, 104 KB)

Yes. There are several tried and tested methods to reduce radon levels in existing homes. The choice of method depends on the radon level and the way your home is built. The HPA has produced a simple colour coded chart to help people select the most appropriate method.
Issue 44 (Autumn 2005) (PDF, 160 KB)

Although radon remedial work must be to a high standard, it is technically simple, and will generally be within the ability of local builders. Many builders have attended training events on radon under a Government programme. These events have been hosted by many local Councils, which may hold trainees' names. The HPA has provided information about radon to the Environmental Health Departments of all Councils, whose staff may be able to advise you. Advice about more difficult cases should be sought from specialist contractors, some of whom advertise in trade directories, or the Building Research Establishment.
Issue 24 (Autumn 2000) (PDF, 104 KB)

It is important that any mitigation work is followed promptly by a measurement, preferably for the normal three month period. A contractor may conduct a shorter test to provide a rapid but approximate guide to the effect of the work, but it is essential that this is supplemented by the longer test, as this is the only way to be sure that radon has been reduced below the Action Level.
Issue 26 (Spring 2001) (PDF, 186 KB)

If reduction is recommended after long-term radon measurements in your home, you should seek advice on this from your local Council, Environmental Health or Housing Department.
Issue 37 (Winter 2003) (PDF, 1.3 MB)

A small void under a solid floor connected by a pipe to the outside. A small electric fan in the pipe continually sucks the radon from under the house and expels it harmlessly to the atmosphere. Modern sumps are often constructed from outside the house so there is no disruption inside.
Issue 1 (Winter 1994) (PDF, 879 KB)

The power of the fan is typically around 75 watts, about the same as a light bulb - and runs all the time. The annual cost will be about £50.00. The fan might need to be replaced about every five years and costs about £120.00.
Issue 1 (Winter 1994) (PDF, 879 KB)

None of these devices can reduce doses from radon much. It is better to prevent radon entry rather than to try and reduce the level once it is in the house.

Increasing the ventilation, especially on the ground floor, will generally not produce a significant or sustained reduction in the radon level. Extractor fans can aggravate radon problems if a suitable air inlet is not provided, as they may draw soil gas into the house.
Issue 38 (Spring 2004) (PDF, 160 KB)

Yes. Starting in 1988, guidelines have been introduced in the most affected parts of the country to reduce radon levels in new homes. The guidelines were incorporated in the building regulations in 1991 and these are revised from time to time to take account of the increasing knowledge about radon. You can check with your local authority to see what regulations apply in your area and look at maps that summarise the areas where preventative measures are required in extensions, conversions, refurbishments as well as new buildings in England and Wales. These maps are available from the Building Research Establishment at www.bre.co.uk/radon/maps.html [outside link].

There are similar maps in the Indicative Atlas of Radon in England and Wales (HPA-RPD-033). A specific report for an individual property can be obtained for a small fee through the UKradon.org website [outside link].

Issue 32 (Autumn 2002) (PDF, 398 KB)

Yes. Using the advice for new buildings will help to avoid the problem. Particular attention should be paid to the join between the old and new parts. Contact the building control officer for your area for further advice and look at maps that summarise the areas where preventative measures are required in extensions, conversions, refurbishments as well as new buildings in England and Wales. These maps are available from the Building Research Establishment at www.bre.co.uk/radon/maps.html [outside link].

There are similar maps in the Indicative Atlas of Radon in England and Wales (HPA-RPD-033). A specific report for an individual property can be obtained for a small fee through the UKradon.org website [outside link].

Radon concentrations in workplace buildings can also reach quite high levels. You should discuss the matter with your employer and ask them to contact the Health and Safety Executive or the Health Protection Agency for advice on the need for measurements.
Issue 37 (Winter 2003) (PDF, 1.3 MB)

The Indicative Atlas of Radon in England and Wales (HPA-RPD-033) summarises the areas with higher risks of finding high radon levels in England and Wales and the final three paragraphs on page 5 of the text discusses radon in the workplace; a specific report for an individual property can be obtained for a small fee through the UKradon.org website [outside link].

The Ionising Radiations Regulations impose a duty on employers to protect workers from exposure to radon. You should contact the local HSE area office or the Environmental Health Department of your local council (whichever you normally deal with for health and safety matters) for advice on whether the regulations are likely to affect your business.
Issue 27 (Summer 2001) (PDF, 183 KB)

The Indicative Atlas of Radon in England and Wales (HPA-RPD-033) summarises the areas with higher risks of finding high radon levels in England and Wales and the final three paragraphs on page 5 of the text discusses radon in the workplace; a specific report for an individual property can be obtained for a small fee through the UKradon.org website [outside link].

The Health Protection Agency provides a measurement service for places of work and publishes a range of leaflets on radon in the workplace. The HPA also provides advisory services under contract to employers, to assist with risk assessments, consultations with certificated Radiation Protection Advisers and personal dosimetry where appropriate.
Issue 43 (Summer 2005) (PDF, 320 KB)

The Indicative Atlas of Radon in England and Wales (HPA-RPD-033) summarises the areas with higher risks of finding high radon levels in England and Wales and the final three paragraphs on page 5 of the text discusses radon in the workplace; a specific report for an individual property can be obtained for a small fee through the UKradon.org website [outside link].

Radon exposures at school are generally lower than at home. Some local authorities in the most affected areas are making measurements in schools and taking action where necessary to reduce radon levels. If you are concerned, do discuss the matter with the head teacher.
Issue 29 (Winter 2001) (PDF, 150 KB)

High levels of radon occur in some caves and mines but a short visit will not cause much exposure.
Issue 3 (Summer 1995) (PDF, 1.3 MB)

No special precautions are necessary because of radon, just the usual need to avoid too much dust.
Issue 32 (Autumn 2002) (PDF, 398 KB)