Radon is a colourless, odourless gas that is produced from the uranium that occurs naturally in rocks and soils. Radon gas disperses quickly outside, but when it seeps into buildings it can collect in greater amounts. The geology of the UK means that people in certain parts of the country, such as Devon, Cornwall, Northamptonshire, and parts of Derbyshire, Somerset, Grampian and the Highlands, are exposed to much higher levels of radon.
Because radon “decays” to form radioactive alpha particles, which can be breathed in, it can cause lung cancer.
The HSE says that radon is now recognised to be the second largest cause of lung cancer in the UK after smoking.
The radon reference site from the Health Protection Agency (HPA) says:
The UK has been surveyed by the HPA and the British Geological Survey. The highest radon areas have been defined as radon Affected Areas. The UKradon website will show you whether your workplace is in one of these Areas.
The HSE advises that underground workplaces such as basements, mines, caves and utility industry service ducts can have significant levels of radon, as can any above-ground workplace in radon Affected Areas.
The Management of Health and Safety at Work Regulations 1999 require employers to carry out a risk assessment and the HSE says that this should include radon in the following circumstances:
The law (Ionising Radiations Regulations 1999) requires employers to take action where radon is present above a certain level (400 bequerels per cubic metre of air). So, if you work in high radon areas of the country, or in poorly-ventilated premises, your employer should monitor the levels of radon at work.
The tests are cheap and simple, and the Health and Safety Executive or your Local Authority Environmental Health Department can put you in touch with someone who can test your workplace for radon. If radon levels exceed 400 Bq m-3, your employer will need to act to reduce them by having a sump and fan installed by a local builder to suck the radon from the soil and vent it outside the building.