Very high radon levels

We are selling our house which my 50 year old husband has lived in for about 15 years, and I have lived here for 10. We finished our basement about 5 years ago and have been down there a lot with our dogs. We just had the buyer’s radon inspection done which came back with an average of 11.0 pCi/l - the normal is below 4 pCi/l!!! The test even spiked up to over 20 at one point in the 2 day period! My husband said he had all the vents closed in the basement and I had a dehumidifier running pretty close to the unit at one point because of some water on the floor from giving my dogs a bath on the unfinished side, and it had also rained a lot so the ground was really saturated so he thinks those things may have affected the test a little, but he is not concerned about the results at all - just upset that we have to spend more money to get the mitigation system installed now to sell the house, but I am TERRIFIED that we are all going to end up with lung cancer now - especially my husband who has spent hours down there playing his X Box!! We are both non smokers but he is an electrician and was exposed to asbestos a long time ago to make me even more worried. Has anyone lived in a house with levels this high and not died of cancer?? I never even knew you were supposed to get your house tested for radon until this!!!

Hi Debra. The first thing is DON’T be terrified. 11.0 pCi/l is not that high. Let’s put things into perspective.

*- Why, according to the DEP, is 3.9 pCi/l OK but 4.0 is bad?

  • Did you know that nearly all foods are naturally radioactive?

  • Did you know that the average radiologic profile of bananas is 3520 pCi/l per Kilogram (2.2lbs) due to the radioactive potassium-40 they contain?*

Here is a link to an excellent (but long) article by Caoimhín P. Connell, a renowned Forensic Industrial Hygienist:

I’m not saying that you should not install a radon mitigation system (you pretty much have to these days to sell a home with an elevated radon level), I’m just saying that the more you understand radon, the less terrified you will be.

1 Like

Thanks Stephen Good post great info .

Great response Stephen! Good info, bookmarked.

I always provide my clients with some perspective on the numbers.

The EPA says you should remediate if above 4.0 picoliters.

I tell them the highest I’ve ever recorded in Baltimore metro is 26.
Sometimes their eyes widen at that and I tell them to hold on and just listen for a moment.

I then tell them that if I test West of the city in the Frederick area I can get up in the 60’s.
Up toward the Pa. line I’ve gotten above 100.

Then I tell them that the State of Maryland has no radon protocols and no State radon program, which tells you something since this is a highly regulated state.

I finish up with Pa. and tell them I talked with one of their radon officials last year and at the end of the conversation I asked him what was the highest level they’ve ever recorded in Pa. It was over 2500 picoliters. Now that provides some perspective!

I hit an 89.4 the other day. Spike over 100 in 4 of the hours. Is my highest to date. I live in a neighborhood that has high radon level. I was at 17. Put a system in in the fall and now am at .3.

First, if the test location was a basement that you spent no time in, then your radon exposure is likely less than you think.

Second, you cannot do anything about the past. You can only do something about the future. Below is a link to the EPA publication for radon. Please read it and make your own mind up.

Best regards,

Debra - I did a test on a house that a realtor lives in, she was curious. The level came back at 136 pCu/l. She has lived in the house for 20 years. She and her husband show no signs of cancer. Like most things in life, knowledge is good, but sometimes can be scary. Will you get cancer in the future? 1 in 3 people get some cancer at some point. Maybe yours will be lung, maybe skin, maybe none. Don’t live your life being afraid of what the EPA says. Remember, they are just another gov’t agency.

It seems as though most of you are trying to diminish the effects of Radon. The EPA does not say that 3.9 is safe. And who are you to say that 11.0 pCi/l is ‘not that high.’

Here’s a radon risk chart. It’s a little dated but useful. Came from a publication NH put out years ago but I believe is still relevant.

I believe 11 needs to be mitigated but no since crying over spilled milk as the saying goes. You can’t do anything about the past and I like what Greg said. There is no telling if you will get cancer in the future but don’t let it keep you up at night.

The EPA does not say levels below 4.0 are safe, there is simply less risk.
It’s all based on actuarial tables etc.

You have one radioactive particle come in contact with one cell there is a chance mutation will occur and possibly cancer. It is simply the world we live in.

This puts the risk into perspective:

Hey check this story about radon.

Radon gas is a danger that can be checked for. The checks should be free.

This recent unwelcome European record… proves the need.
Tests have found a home in Castleisland, north Kerry, with one of the highest amounts of naturally-occurring radon ever found in Europe only a few kilometres from the record level detected in 2003 .
Checks for Radon gas should be free in Ireland.
The principal source of exposure to radiation in the home is from radon gas. Radon comes from the ground and may accumulate in your home to unacceptable levels. Long-term exposure to the radioactive gas can lead to lung cancer. Therefore, we recommend that everybody should have their home tested for radon, regardless of where they live or how old their house is.
Checks for Radon gas should be free in Ireland .
It makes perfect business sense… any home that was found with high levels would require work. The scheme if managed effectively… would be self funding.
If the checks can not be free for everyone… they should at least be free in known high radon gas areas.
There are people using scams to make money out of the fear of radon gas… they prey upon the vulnerable… the elderly and naive in Ireland.
Radon Gas Map of Ireland, detailing areas known to be at high risk.

Press Association news confirms the need for a national policy and it has to be free.
Thousands of households are living unaware with a cancer-causing gas, experts have warned.

Tests have found a home in Castleisland, north Kerry, with one of the highest amounts of naturally-occurring radon ever found in Europe only a few kilometres from the record level detected in 2003 .

The Radiological Protection Institute of Ireland (RPII) said that out of 5,000 homes tested in the nine months to June, more than 800 showed high levels.

Radon is the second biggest cause of lung cancer after smoking and is directly linked to about 200 deaths from the disease in Ireland each year.

Dr Ann McGarry, RPII chief executive, said tests show Ireland has a significant problem with the colourless, odourless gas in homes.

“We predict that there are thousands more homes across the country with high levels of radon gas,” she said.

“To date, only a very small proportion of these homes have been identified. Exposure to high radon levels causes lung cancer and many people are unknowingly living with very high levels in their homes. The only way people will know if it is in their homes is by testing.”

Record radon levels in Donegal. A house in Lifford has been found to have the highest levels of radon gas in County Donegal
Donegal’s worrying levels of radon gas
Donegal County Council has been asked to put measures in place to promote awareness of the dangers of Radon Gas after it emerged that five per cent of homes in the county have high levels of cancer causing radon gas.
Radon, a colourless, odourless and tasteless radioactive gas is linked to up to 200 lung cancer deaths each year in Ireland. Figures from the Radiological Protection Institute of Ireland (RPII) show that 562 houses here have high levels of the gas.
At a meeting of the local authority Cllr. Dessie Larkin raised the issue and explained there are a number of areas outside Letterkenny which have high concentrations of the potentially lethal gas.

Record radon gas level found at Co Cork office
An office in Mallow, Co Cork, has been identified as having the second highest reading ever detected in the country for the radioactive gas radon.
The Radiological Protection Institute says the level present at The Corkman newspaper was 60 times higher than the acceptable limit.
Radon is the second biggest cause of lung cancer in Ireland, causing up to 200 deaths per year.
Advertisement Radon is a colourless, odourless, tasteless gas which occurs naturally from the decay of radioactive uranium in rocks and soils. It only becomes a problem when it builds up in basements of houses and offices. The institute said levels at one office of The Corkman newspaper in Mallow would be equivalent to receiving 39 chest X-rays per day, or nearly 10,000 in a working year.
However, the RPII said the office in question was largely unoccupied, and so the risk to employees was significantly reduced. The RPII’s Chief Executive, Dr Ann McGarry, said over 100,000 homes and offices are estimated to be at risk and while the Corkman took the appropriate action, many others were being irresponsible for not testing for radon.

Radon is created when uranium in rocks and soil breaks down and it is regarded as a class one carcinogen. Experts estimate that in Ireland a 70-year lifetime exposure to radon at the acceptable level - 200 becquerels per cubic metre (Bq/m3) - carries a one in 50 chance of contracting fatal lung cancer. That is twice the risk of dying in a road accident.

The RPII said smokers, or reformed smokers, face up to 25 times greater risk from radon than non-smokers.

An interactive map is available on the RPII’s website - - for householders to see whether their home or workplace is in a high radon area.
Free Radon Gas checks all homes in Ireland.
Measurement of radon levels in Ireland.
Information Radon Gas In Ireland
Radon is a naturally occurring radioactive gas that results from the decay of uranium in rocks and soils. The gas is colourless, odourless and tasteless and can only be measured using special equipment. When radon surfaces in the open air, it is quickly diluted to harmless concentrations, but when it enters an enclosed space, such as a house or other building, it can sometimes build up to unacceptably high concentrations. Radon from the ground enters buildings chiefly through cracks in floors or gaps around pipes or cables.

Radon decays to form tiny radioactive particles, some of which stay suspended in the air. When these particles are inhaled into the lungs, they give a radiation dose that may damage cells in the lung and eventually lead to lung cancer.
Radon concentration is measured in becquerels per cubic metre of air (Bq/m3) - the becquerel is a unit of radioactivity and corresponds to one radioactive disintegration per second.
National Radon Survey

The National Survey of Radon in Irish Dwellings was conducted by the Radiological Protection Institute (RPII) between 1992 and 1999. The RPII is the national organisation with regulatory, monitoring and advisory responsibilities in matters relating to ionising radiation. The survey assessed radon levels in Ireland and identified those parts of the country where high indoor radon levels are more likely to be found.
The survey involved measuring radon over a 12-month period in a random selection of houses in each 10 x 10 km National Grid square throughout the country. The results were used to predict the percentage of houses in each grid square in which the radon concentration is in excess of 200 becquerels per cubic metre (Bq/m3) - the National Reference Level. Grid squares where the percentage is greater than 10% are designated High Radon Areas.

The RPII has published the results of the National Survey of Radon in Irish Dwellings and has produced a map entitled “Radon in Irish Dwellings”, ,which shows the predicted percentage of houses above the National Reference Level for each grid square. You can view county radon maps by clicking on the county. You can also view a table that summarises the results of the radon survey for each county.
Measuring radon

The RPII recommends that all householders have their homes tested for radon.
The level of radon in a house can be measured simply and inexpensively. It is usually carried out by placing two small testing devices (detectors) in the house for three months. At the end of this period, the detectors are sent back to the testing laboratory for processing. This procedure can be carried out entirely by post. A three-month measurement period is recommended because radon levels in a house can vary considerably from day to day as a result of changes in the weather conditions, ventilation, building usage, etc.
The radon measurement service is confidential. The RPII will not release the result of any measurement to anyone other than the person who requested the original measurement.

Building Regulations and radon
Since July 1998, every new house or long-stay residential building must incorporate some degree of radon preventive measures at the time it is built, in accordance with the revised Building Regulations of 1997. The degree of radon protection required depends on whether the site is located within an area with high or low levels of radon.

Two levels of protection are laid down in the Regulations: a basic or precautionary level that applies to new buildings in all parts of the country and a more advanced level that applies to new buildings in designated High Radon Areas.
The Building Regulations require that new buildings in all parts of the country include a potential means of reducing radon levels, should high levels be found in the completed building. In the case of dwellings of normal construction, this is usually achieved by means of a radon sump, as described in the Department of the Environment, Heritage and Local Government’s publication " Radon in Buildings " , which can be purchased from the Government Publications Sale Office, Molesworth Street, Dublin 2, Tel: 01 661 3111. The RPII recommends that, once occupied, all new buildings should be tested for radon. If the radon level is above the National Reference Level, the radon sump or some other means of reducing the radon levels should be activated.

In High Radon Areas, the Building Regulations stipulate that, in addition to providing a potential means of reducing radon levels, measures should be taken to protect the building from radon in the ground. For a residence of normal construction, this means that a fully sealed low-permeability membrane should be provided in addition to a radon sump.

For further information contact, contact the Radon Department of the RPII by e-mail at or telephone Freephone Radon 1800 300 600.
Radon in the workplace

Exposure to levels of high radon can occur in the home, in school or in the workplace. Indoor radon levels vary greatly from one building to another and in some workplaces, radon can be a significant source of occupational exposure to ionising radiation.

Occupational exposure to natural radiation sources, including radon, has been subject to regulatory control in Ireland since May 2000. This change is in line with the most recent revision to the Euratom Basic Safety Standards Directive (Council Directive 96/29/EURATOM), which establishes a common basis for radiation protection legislation in all EU Member States.

In Ireland, the laws and regulations needed to comply with the Directive were brought into force by the Radiological Protection Act, 1991 (Ionising Radiation) Order, 2000 (Statutory Instrument 125 of 2000). The Order sets a National Reference Level for radon in workplaces of 400 Bq/m3 averaged over any three-month period. In accordance with the Order, an employer or self-employed person responsible for a workplace is required to measure radon levels in the workplace if he or she is directed to do so by the RPII. The RPII has produced Guidance Notes for Planning Radon Surveys in Workplaces, which should be studied when planning radon surveys in workplaces.

If radon levels in a workplace are found to exceed the National Reference Level, the Order requires that the employer take measures to safeguard the health of workers. The employer must evaluate whether remedial measures to reduce the radon levels in the workplace should be undertaken. Where this evaluation shows that remedial measures are necessary, the employer must implement such measures as soon as is practicable.

Where remedial measures are not shown to be justified or where they fail to bring levels below the National Reference Level, the employer must apply radiation protection measures in the workplace. Such measures might, for example, include the organisation of work schedules to reduce exposure to radon, making and keeping radon exposure records, medical surveillance and controlling access to areas in the workplace where radon levels have been shown to be high.

The RPII provides a radon measurement service (consisting of two radon detectors) to householders at a price of 40 euro. You can buy additional detectors for 24 euro each.

An A1 size version of the map “Radon in Irish Dwellings” can be purchased directly from the Institute for 15 euro.
How to apply

Why should someone be entitled to anthers time and skill for free? Tests should absolutely not be free and if a high level is detected and has to be mitigated you should be thrilled to have paid the technician and not an oncologist.

Keep in mind that it is important to test over a long period of time. Even having doors open and close on the main floor can cause the air to be pulled from the basement. The levels during winter may be totally different than summer.

While it can take a bit to do, I’d recommend getting a long term radon test. It takes 90+ days but it takes into account the fluctuations that happen day by day. The rate might be 20 pCi/l one day and 0.5 pCi/l the next. Alternatively, a short term test would still be good (10 to 90 day test). Obviously, these two aren’t ideal when selling your house, but I would highly consider doing these in your new home.

If you are purchasing a new home and the seller conducted a radon test, keep in mind that the test may only be over 1-2 days and could be very inaccurate.