Radon gas

Radon is a naturally occurring, radioactive gas. All homes have some radon gas in the atmosphere, however, if it exceeds a certain level, it can be dangerous. This page looks at how you can test radon levels in your home and what you can do to reduce them.

What is radon gas?

Radon is the biggest source of radiation in our lives and is found at varying levels across Britain. A naturally occurring, radioactive gas, it's formed by the breakdown of uranium found in all soil and rocks. Outdoors, it disperses harmlessly into the air, but once it finds its way indoors, through gaps and cracks in floors and walls, it may build up to potentially harmful levels.

What are the dangers?

As radon decays, it releases tiny radioactive particles into the atmosphere which, when breathed in, can damage the lungs. Exposure to high levels of radon gas causes a higher risk of lung cancer. If you smoke, these risks are greatly increased.

Am I at risk?

Certain areas of the country with high radon levels have been designated Radon Affected Areas, and anyone living in these areas is advised to test their homes for radon and take steps to reduce levels if necessary. Detailed maps can be found in the publication available from the Health Protection Agency (HPA) website.

However, there's no easy way to tell whether your home is likely to have high levels of radon gas, as this depends on many factors, so even if you live outside these areas, it's a good idea to test to be on the safe side.

How much is too much?

The 'action level' set by the Health Protection Agency is ten times the average level. If the amount of radon in your home exceeds the action level, you are advised to do something to decrease it. Even if the amount is below the action level, you may wish to reduce it further, as studies have found that exposure at lower levels can still increase the risk of lung cancer.

What can I do if radon levels in my home are too high?

The most effective way of reducing radon levels is to prevent the gas getting into your home in the first place. The best way to do this is by extracting the gas from underneath the floor before it can seep upwards. If your home has a solid floor, a sump can be installed to extract the radon from beneath the house and expel it harmlessly outside. If your home has spaces underneath the floor, these can be ventilated using airbricks or a small electric fan.

Keeping your home well ventilated may also help, but will not reduce levels significantly.

How much will it cost?

A fan will set you back around £100-£150 and a sump £500-£700. Fans and sumps then cost around £50 a year to run.

What if I rent my home?

If you rent your home and are concerned about radon gas, you should speak to your landlord about it and ask them to test the property for you. If they refuse, you may have to buy a radon detection pack yourself to test your home. If the amount of radon in your home is above the action level, it's up to your landlord to do something to reduce it, just as it's up to them to deal with any structural disrepair problems. You can find out more here about getting repairs done if you rent from a private landlord or from the council or a housing association.

If you rent your home privately and your landlord is refusing to do anything about the problem, you may be able to get help from the council's environmental health department, as high levels of radon gas can be seen as a 'statutory nuisance', harmful to your health.

Where can I find out more?

You can find more information and advice on dealing with radon gas from the Building Research Establishment (BRE).

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Last updated: 29 December 2014

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