Radon Gas in the Thanet District
What is it?
Radon gas, which emanates naturally from rocks and soils in the
ground, mixes with air and rises to the surface where it is quickly
diluted in the atmosphere. Concentrations in the open air are very
low. However, radon that enters enclosed spaces, such as buildings,
can reach relatively high concentrations in some circumstances.
- Radon is a naturally occurring radioactive gas.
- It comes from the minute amounts of uranium that occur
naturally in most rocks and soils.
- It has no odour, taste or colour (at standard temperature and
pressure).
- It can only be detected by using specialist equipment.
- Radon is present throughout the country and in Thanet at levels
that pose a low risk.
The Health Protection Agency (HPA) measures radon levels in
Becquerel per cubic metres of air (Bq m-3) and have advised the
government that a reading of 200 Bq m-3 in homes should be
considered the ‘Action Level’. This is the level at which action
should be taken to reduce the radon concentration.
What has changed?
The Health Protection Agency and the British Geological Survey
have jointly produced new information on radon Affected Areas in
England and Wales. A new atlas was published on 12 Nov 2007 giving
an overview of ‘Radon Affected Areas’ by km2 of the national grid.
The atlas is indicative rather than definitive (ie. it refers to
the maximum percentage band that exists within each km2 grid). This
material replaces the existing Radon Atlas of England and Wales.
These maps may be viewed on www.hpa.org.uk
According to the new indicative atlas, most of the Thanet
District now falls within a ‘Radon Affected Area’ (defined as an
area where there is a 1% or more risk of homes being above the 200
Bq m-3 ‘Action Level’), and it highlights maximum percentage bands
of 1-3% for most 1-km2 grids of the Thanet District.
However, this does not automatically mean that an individual
property within these 1-km2 grids will have a radon problem. More
accurate radon potential estimates for an individual home can be
obtained through the following website:
www.ukradon.org
Where does it come from?
Radon gas is generated by the breakdown of radioactive radium,
which in turn is the decay product of uranium, found in the earth's
crust [1]. It is present in small quantities in
most soils and rocks, although the amount varies from place to
place. It is particularly prevalent in granite and limestone areas,
but not exclusively so. Radon levels vary not only between
different parts of the country, but even between neighbouring
buildings. Most homes even in the higher radon affected areas will
not have a radon problem.
What can it do to me?
Exposure to high concentrations of radon can pose serious risks
to health.
If you breathe in high concentrations of radon decay particles
they can damage your lung tissue. The radiation decay products
ionize genetic material, causing mutations that sometimes turn
cancerous. Radon exposure is the second major cause of lung cancer
after smoking[2].
How does it get into my home?
Air from the soil seeps into the lower pressure area of the
house through cracks and gaps in the floor or walls. In some areas,
this air will contain Radon gas. These Radon levels may become
concentrated inside buildings and rise above the ‘Action
Level’.
What if I live in an affected area?
The estimated radon potential for an individual home can be
obtained through the following website for a small fee.
www.ukradon.org
The government recommends that people
in affected areas test their houses for radon. The test involves
monitoring radon in the home with a simple, safe device for a
period of three months. It costs around £40 and is available to
anyone.
Test Kits are available from the
Health Protection Agency at:
http://www.hpa.org.uk/
HPA Radon Hotline: 0800 614
529
The government, the HPA and the Building Research Establishment
(BRE) all recommend that if householders' indoor radon levels are
found to be above the ‘Action Level’ they should take radon
reduction measures as soon as practical - and then take the test
again to give themselves peace of mind that the measures have
worked.
How do I protect myself and my property?
It is your average exposure to Radon that matters. Short-term
exposure to high levels is not significant, if over the long term
your average exposure is low. This means that if you have detected
a problem, you can plan a solution that suits you, your house and
your Radon level. Having decided on a solution, you should
implement it as soon as practicable. The best approach is to stop
Radon entering the house. If this is not possible, you need to be
able to remove it when it gets in.
The aim is to reduce indoor radon levels to well below the
‘Action Level’. There are a number of ways in which this can be
achieved.
Following publication of updated BRE guidance, there are no
special requirements for radon protection in new buildings and
extensions in Thanet. For more information, you can call the Radon
Hotline at the Building Research Establishment on 01923 664707.
Further Information
If you require any more information about Radon in the Thanet
District you can contact the Environmental Protection Team on 01843
577000.
Advice can also be obtained
regarding Radon in the Workplace from: http://www.hse.gov.uk/radiation/ionising/radon.htm
References
[1] N.N. Greenwood and A. Earnshaw
(1994) ‘Chemistry of the Elements’, Oxford: Pergamon
Press, 1454-55.
[2] Catelinois, O; Rogel A; Laurier
D et al. (May 2006) ‘Lung Cancer Attributable to Indoor Radon
Exposure in France: Impact of the Risk Models and Uncertainty
Analysis’, Environmental Health Perspectives 114 (9):
1361–1366: National Institute of Environmental Health Science