Radon Ingress: How to Recognize it And What to do About It

What is radon ingress? How do you know if your house is affected by this type of problem and if so, what can you do about it?

Since it is a dense chemical element, radon tends to accumulate in the lower levels of a building. Therefore, radon levels tend to be higher in basements and ground floors, as well as areas that are poorly ventilated. This gas is produced by the degradation of uranium, which is naturally present in the ground. 

Radon gas is colourless and odourless, therefore not recognizable by humans without the help of a machine.  

Why is radon gas dangerous?

In small quantities and areas with proper air circulation, this gas is not considered a health hazard, as it is diluted within the atmosphere. However, radon gas can become a major problem whenever it starts to accumulate in a confined space. It enters the house through dirt floors, through basement floor drains, through cracks in walls and/or floor slabs and, lastly, through joints that are not properly sealed on branch pipes and drainpipes.

Photo: The lung association

The effects of being exposed to radon

High-density exposure to radon gas is the second most frequent cause of lung cancer (10 to 16% in Quebec), right after cigarettes. In the past few years, radon has become a major concern for various government and health organizations that have decided to document the problem and the various risks relating to radon ingress.

Contrary to what one might think, radon does not cause other respiratory disorders including emphysema, allergies and bronchitis. However, long-term exposure greatly increases the chances of developing lung cancer, especially for people who are also smokers and who therefore multiply the risk factors.

That being said, the effects of radon on living beings are still being studied and more is learned every year about the impact of this volatile element.

Photo: saphymo.fr

Diagnosing a radon problem in your home

There is no consensus between experts regarding the maximum amount of radon that can be found inside a building before it turns into a problem. However, various distinct sources agree that the directive issued by Health Canada is the right one. The documentation prepared by this branch of the Canadian government states that if the radon level surpasses 200BQ/m³ inside the building, corrective measures will have to be applied within the next two years.

With a result of more than 600BQ/m³, these measures have to be applied in the coming year. According to pq.poumon.ca, one out of ten houses is faced with a radon problem that should be solved as soon as possible, to avoid lung illnesses that are caused by exposure to this gas. It should be noted, however, that Quebec regulations provide for a maximum limit of 800 Bq/m3, which embodies the old Canadian standard.

How to use a dosimeter

Radon ingress can be tested by oneself, using a dosimeter. This tool can be bought for approximately 40$ and is used to test the BQ/m³ level. You can also contact a building inspector who will be able to do all the tests for you, so you can get a better idea of the situation.

Beware: avoid door-to-door salespeople who offer radon tests. More often than not, they are charlatans who will invent non-existent radon problems or who will not be able to apply the proper remedial actions.

Radon infiltration: watch out for preconceived ideas

While one might tend to believe that radon infiltration is a problem concerning only old houses, it seems that this is completely false. In fact, the opposite would be true.

Indeed, a study put forward by Aaron Goodarzi (head of the Research Chair in Radiation Exposure Diseases at the University of Calgary) and mentioned in La Facture (the Quebec equivalent of CBC's marketplace) shows that the more recent a home is, the more likely it is to display high levels of radon.

As evidence, he argues that 21% of homes built after 1974 have radon levels above 200Bq/m3. For houses built after 1974, this proportion drops to 11%.

Another myth rejected: the one suggesting that the presence of radon is a problem only in winter. If the use of air conditioners or the opening of windows in the summer can facilitate the evacuation of some of the harmful gas, it should be noted that this is not always the case. Indeed, the researcher points out that in some houses, it is possible to see a concentration of radon as that is as high in summer as in winter.

Solutions to fix a radon ingress problem

Once you have gotten the negative results to the diagnosis, it’s important to contact a qualified contractor who will help you fix the issues that are causing this radon ingress problem. The proper method to avoid radon ingress is to start by sealing all the cracks and openings at the floor level and/or touching the ground, as well as the joints between floors and walls.

To solve a radon ingress situation, another solution that often works is to install a system of depressurization wells under the cement slab, to create negative pressure, which will help evacuate the gas. This must be done by a certified contractor. 

The problem could also be located in the basement or the crawl-space under the house. Oftentimes, these spaces are poorly isolated and not well ventilated, which can cause radon gas accumulation. For more information, check out our article about crawlspace ventilation and insulation.

Do you need to have your home decontaminated to fix a radon problem? Check out our article Price of a decontamination project.