What is Radon Gas

Radon is a naturally occurring radioactive gas released from the ground. It forms as uranium and radium break down in rocks and soil, and it can seep into homes, workplaces, and other buildings without any obvious signs. Because radon continuously decays, it emits radiation that can be harmful when breathed in.

In England, radon exposure is recognised as the second leading cause of lung cancer, responsible for up to 2,000 fatal cases every year across the UK. The risk increases when radon builds up indoors, particularly in areas classed as higher-risk by UK radon maps. The good news is that radon levels are simple and inexpensive to test, and high readings can be reduced with straightforward mitigation work.

All employers in the UK are required by law to review radon risks within their premises as part of their health and safety obligations.

For further information on the health impact of radon, visit the Health and Safety Executive: www.hse.gov.uk

While radon is present everywhere at low levels, it only becomes a concern when concentrations rise indoors. Testing identifies this quickly, and effective solutions are available to bring levels back down to safe limits.

Home Testing → Commercial Testing →

Radon Testing Header

How does radon enter a home or workplace?

Radon, because it is a gas, is able to move though spaces in the soil or fill material around a home or workplace's foundation. Most buildings tend to operate under a negative pressure - this is especially true in the lowest portions of the building and during the heating season. This negative pressure acts as a vacuum (suction) that pulls soil gases, including radon, into the lower level of the structure.

What can cause a negative vacuum?

Heated air rising inside the building (stack effect).
Wind blowing past a building (downwind draft effect).
Air used by fireplaces, wood stoves, and furnaces (vacuum effect)
Air vented to the outside by clothes dryers and exhaust fans in bathrooms, kitchens, or attics (vacuum effect).
Radon can enter a building through the floor and walls -- anywhere there is an opening between the building and the soil.
A basement, of course, provides a large surface area that contacts soil material.
Major Radon Entry Routes
Cracks in concrete slabs.
Spaces behind brick veneer walls that rest on uncapped hollow-block foundations.
Pores and cracks in concrete blocks.
Floor-wall joints.
Exposed soil, as in a sump or crawl space.
Weeping (drain) tile, if drained to an open sump.
Mortar joints.
Loose fitting pipe penetrations.
Open tops of block walls.
Building materials, such as brick, concrete, rock.
Well water (not commonly a major source in Welsh homes).

What happens after radon gets into a building?

How can I find out if my home or workplace has a radon problem?

Radon is completely colourless, odourless and tasteless, so the only reliable way to know how much radon is in your property is to carry out a radon test. At Radon Safe UK, we advise all homeowners and employers to test their buildings, regardless of location or building type.

Every property behaves differently when it comes to radon. Factors such as local ground conditions, construction methods, age, maintenance and even how the building is heated or ventilated can all affect indoor radon levels. Because of this, results from neighbouring properties cannot be used to predict your own radon levels, and old test results may no longer be accurate if a building has been extended, modernised or experienced changes in its ventilation or heating systems.

A correctly performed radon test gives you clear, reliable data. It allows homeowners and employers to decide whether further action is needed to protect their family or workforce from the known health risks associated with radon exposure.

Imagine Seeing This on Your Drive…

You’re travelling from Somerset into Devon when a sign appears at the side of the road:

“WARNING – RADIOACTIVE AREA”

How would you react?

Would you simply carry on, or would you think twice and turn back?

Now picture similar signs on the outskirts of Banbury, Northampton, the Yorkshire Dales, and across parts of Wales, Scotland and Northern Ireland. It would instantly feel like a serious public safety issue – something you’d expect clear warnings about and proper action taken.

The reality is that many of these areas already have naturally elevated radon levels. There are no roadside signs, no visible markers and no obvious clues. Yet radon remains a significant health risk, particularly in the regions identified by UK radon maps as higher-risk zones.

Check Your Location →