Radon is an element (no. 86 in the periodic table) that occurs as a colourless, odourless radioactive gas. It is formed by the radioactive decay of the small amounts of uranium that occur naturally in all rocks and soils. Radioactive elements decay and emit radiation. Any exposure to this type of radiation is a risk to health – radiation is a form of energy and can cause damage in living tissues increasing the risk of cancer. Radon can be found everywhere we go, including Cornwall.
What is radioactivity and radiation?
Radioactivity occurs when unstable elements, such as naturally occuring uranium, thorium and radon, break down. When this happens, energy is released and different elements form. The new elements may also be unstable, so the process is repeated until a stable element is formed. The energy given off from these changes is radiation.
Radiation occurs as alpha or beta particles, or gamma rays. Alpha particles contain more energy and are absorbed over a smaller area and are therefore more harmful than beta particles or gamma rays.
Our exposure to radiation
We are all exposed to radiation from natural and man-made sources. Just 20 Bqm-3 (the average UK background radon level) gives us half our exposure to radiation from all sources.
Higher radon levels give higher exposures: that is why it is important to find out the levels in your home, and in your school or workplace.
How much radon is dangerous?
The amount of radon is measured in becquerels per cubic metre of air (Bqm-3). The average level in UK homes is 20 Bqm-3. Public Health England (PHE) recommends that radon levels in homes should be below 200 Bqm-3 (annual average) – the ‘Action’ level – and preferably below the ‘Target’ level of 100 Bqm-3 for smokers and ex-smokers. The Health and Safety Executive states that employers must keep workplace radon levels below 300 Bqm-3 (annual average) to comply with UK law.
For more deatiled technical information about radon, and more information about radon locations in the UK