Radon is a naturally occurring radioactive gas that can seep out of the ground and build up in workplaces.
Most radon gas breathed in is immediately exhaled and presents little radiological hazard. However, the decay products of radon behave more like solid materials than gas and are themselves radioactive.
These solid decay products attach to atmospheric dust and water droplets which can then be breathed in and become lodged in the lungs and airways. Some decay products emit particularly hazardous radiation called alpha particles which cause significant damage to the sensitive cells in the lung.
Radon is now recognised as the second largest cause of lung cancer in the UK after smoking.
Workplaces that may be affected
The UK has been extensively surveyed by the Health Protection Agency and the British Geological Survey. The highest radon areas have been defined by Government as Radon Affected Areas. An Atlas indicating the locations of Radon Affected Areas has been produced by the HPA.
Underground workplaces such as basements can have significant levels of radon as can any above ground workplace in Radon Affected Areas. All workplaces including factories, offices, shops, schools, nursing homes and health care centres can be affected.
Under the Health & Safety at Work etc Act 1974 employers must ensure the health and safety of employees and others who have access to their work environment. The Management of Health & Safety at Work Regulations 1999 require the assessment of health and safety risks and should include radon in the following circumstances:
- Ground floor rooms in above ground workplaces inside Radon Affected Areas require a Radon Risk Assessment.
- All below ground workplaces in the UK irrespective of whether they are inside a Radon Affected Area require a Radon Risk Assessment.
The Ionising Radiation Regulations 1999 come into affect where radon is present above the defined level.
Testing for Radon
As part of a risk assessment process, radon monitoring should be conducted in any building or basement where its location suggest that elevated levels may be found and exposure to employees and others are possible. Radon levels in buildings vary widely throughout any given day and season. For this reason measurements are usually made over a period of 3 months and correction factors used to determine worst case winter results. Experience has shown that radon concentrations can differ significantly even in adjacent buildings, so results from nearby properties are not a reliable indicator. The number of radon monitors and placement will depend on the nature and size of the building.
We are able to offer a Radon Risk Report for your company which will determine whether or not you are inside a Radon Affected Area. If you fall outside of an Affected Area and work exclusively above ground
you will legally not need to take any further action.
What will the results mean?
If radon levels are found to be less than those specified in the Ionising Radiation Regulations 1999 at the initial measurement, no action will be required other than to remeasure on a predefined basis, normally between 5 and 10 years depending on the results. If radon levels are above the designated action level specified in the Regulations, measures would need to be taken to reduce exposure such as engineered measures or occupancy restriction and the measurement period is likely to be much more frequent.
For more information about Radon, click here to download our Radon Risks brochure.