Radon: Breathe easy by tackling this silent earthborn enemy

Kya deLongschamps on the dangers associated with Radon and the measures to deal with this potentially deadly gas that few of us seem to know much about.
Radon: Breathe easy by tackling this silent earthborn enemy
Radon map of Ireland available at

Radon kills more people in Ireland each year than carbon monoxide poisoning, but few of us seem to know much about this silent earthborn enemy.

It’s a potentially deadly ventilation failure in as many as 7% of Irish homes.

You may already have a stand-by radon sump (not yet in use) and have no idea what it is — it’s that funny capped off pipe coming up out of the footpath.

What is Radon?

Radon is a naturally occurring radioactive gas present in rocks and soil, caused by a breakdown of elements in the Earth’s crust.

During this ongoing decay, microscopic particles of radon (radionuclides) from uranium 238 leak up out of the ground and can enter buildings, supped up through holes in the foundation around conduits, cracks, gaps in boards and other inventible tiny avenues.

Accelerated into the atmosphere by the difference in pressure from inside to out, every building, commercial and domestic has some radon, and Ireland has some of the highest radon levels in Europe, most surfacing and dissipating harmlessly.

Radon is a naturally occurring radioactive gas.

Radon is a naturally occurring radioactive gas.

Where radon levels are significantly concentrated in the confines of a poorly ventilated home, it is a known human carcinogenic.

This radioactivity is a form of energy, specifically damaging tissues in the lung, and contributing at least 250 cases of lung cancer in Ireland every year, and smokers are made more vulnerable to lung disease by the long-term inhalation of radon.

Radon can be prevented from entering a building with a well installed radon barrier in polyethylene (similar and sometimes in lieu of a DPC) and used in concert with a radon sump where the gas gathers and is drawn out passively or pushed out using a fan.

Stand-by sumps with a pipe rising out of the ground and capped if not needed, are a feature of houses built to Building Regulation standards since July 1998.

Ireland & Radon

A survey of 11,000 homes was carried out by the Radiological Protection Institute of Ireland (now part of the Environmental Protection Agency)

between 1992-1999

Parts of Ireland were consequently mapped and shown to have excessive readings for radon, above the safe National Reference Level (or action level) of 200 Becquerel (units of radioactivity) per cubic metre (Bq/m3).

The most dramatic reading found in the country to date is 49,000 Bq/m3 recorded in a home in north Kerry in 2003- equivalent to several chest X-rays per day.

Radon map of Ireland available at www.epa.ie

Radon map of Ireland available at www.epa.ie

The average indoor radon level found for an Irish house over a period of one year is 89 Bq/m3. Interestingly the average level in UK homes is only 20 Bq/m3.

Some granite rich geology produces more radon gas. You can find the indicative map at the EPA website, but keep in mind, it is only a grid-mapped guide.

Heavy swathes of the north-west and the south-east indicate significantly high readings of radon in the original RPII survey (about 30% of the Republic with 10% of homes predicted to have high levels).

However, incidental areas of high concentration above the action levels of 200 Bq/m3 appear all over the country from Tralee to Louth.

Log onto www.epa.ie/radiation/radonmap/ to find an interactive map, and enter your address for an indication of the radon risk.

There’s an indicative Atlas for Northern Ireland based on a survey by the PHE and the British Geological Survey of 23,000 homes available at ukradon.org.

Testing for Radon

National mapping does not inoculate your family against the cumulative health impact of radon.

Over nine months from September 1, 2010 to June 1, 2011, 5,000 homes tested by the RPII, revealed 800 with high radon readings, 700 were up to 800 Bq/m3 — clearly efforts at educating homeowners nationwide to test and take action had not penetrated.

A house in a predictably hot spot for radon may have low readings due to its specific position and radon protection devices (barrier and sump) within the structure.

A house in an area of negligible radon on the EPA map may be urgently in need of remedial works to offset a high radon reading.

Radon testing is effortless, and the EPA recommends testing even for new homes for three months to allow for day to day variations in the air quality during occupancy.

Two small detectors the size of a digestive biscuit, ordered online, arrive by post, and are placed in the home, one in the main bedroom, one in the principle living room for a period of three months.

They are then returned for analysis, again by post. Use at least one detector per 400m2. The supply of the detectors, analysis, results and recommendations from the EPA is €56.90.

There are also trusted private testing consultants available and listed at the EPA including Alpharadon who do a testing service complete for just €40.


Dealing with Radon

Retro-fit measures are vital to deal with a worryingly high reading from testing (this is in the view of some UK scientific experts more like 100 Bq/m3 plus).

The work is not wildly expensive or complicated. The radon has to either be prevented from entering and/or expelled from the building before it adds to a dangerous airborne burden.

The price point for retro-fit works will be anything from €50-€500 to seal openings in floors and improve passive ventilation downstairs only (installing wall and trickle vents), or to add mechanical measures to improve air exchange to move radon outside.

Where the burden of radon is 1000 Bq/m3 or more in a house without a sump, a relatively discreet retro-fit of an under-floor radon sump and a powered fan using a 110mm pipes, starts in the area of €850-€1,200 for one sump excavated (it’s a bucket full or two from the hardcore) and made good for a standard sized house.

The fan will cost in the area of €150-€200 to run pa. A longer pipe reaching over the eaves, on the exit pipe of an existing stand-by sump, fitted with a fan if needed, can also solve the radon issue within hours.

Whatever you decide to do, retest the house for radon after the works. EPA provides a free post-remediation service to homeowners.

A booklet ‘Understanding Radon Remediation – A Householder’s Guide’ (PDF) will help you learn more about the solutions available and how best to deal with the problem. 

In addition, the EPA holds a list of companies who are known to provide a radon remediation service.


Freephone: 1800 300 600.

Remedial work for radon control falls under the two year tax credit scheme, the Home Renovation Incentive Scheme.



The mapping provided by the EPA, above (www.epa.ie) will indicate if your potential, or new house is in a radon-affected area, but it is only a guide to major pockets known to the Radon Protection Institute of Ireland.

Being in a high radon area does not mean a property has dangerous levels of radon and if you’re buying, the seller has no legal requirement whatsoever to present you with radon test results for the house, and the results of past testing are confidential.

The Building Regulations since July 1998, stipulate a radon barrier must be fitted in the construction of all new homes, and a quality damp-proof course acting as a radon barrier should be part of the basics in any extension work too.

Ask for any available certification for such work or reports for past testing.

The EPA does not regard site testing (before a new house is built) as reliable. If you have concerns, test the house for three months after you have moved in. This will indicate if you need to activate stand-by measures already in place.

Unoccupied houses generally have higher radon levels, due to lack of regular ventilation.

Even if the house next door has been checked and proven to have a low readings for radon, it’s worth investigating further, especially where only basic radon protection (a damp-proof course for example), is in place.

Radon levels can vary from site to site, and damage to the integrity of a radon barrier are unseen.

Ask your solicitor about the prospect of retention from the purchase price on a second-hand house to pay for any remedial work that may be required to improve the radon levels after a high test result.

This might entail activating a stand-by radon sump with a fan or installing a sump and works from the outside of the house for example. All homes have radon.

The levels are not higher or lower depending on the address, type of build or layout.

“You cannot make any confident prediction of your radon levels based upon the location, construction or age of your house.

“The Radon Protection Institute of Ireland recommends all householders, especially those living in high radon areas, should test for radon” said the EPA. For prospective vendors, this just makes sense.

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