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Radon in Basements: Causes, Signs & Dangers

furnace system in the basement

As a homeowner, one of the most important duties is protecting your loved ones from anyone or anything that may seek to harm them. One of the precautionary measures that homeowners undertake is preventing exposure to radon gas. This is a colorless and odorless gas that can have adverse health effects once exposed to it for an extended period.

While many people assume that radon gas is only present in homes with a basement, this is a very dangerous assumption because radon is present in every home. It is considered dangerous because people rarely notice it until they start experiencing its harmful side effects.

In this article, we will explore the causes, signs, and dangers of radon gas in your basement to better protect your loved ones from exposure.

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What Is Radon Gas?

If you are unfamiliar with radon gas, it is a naturally occurring radioactive gas that can cause lung cancer when exposed for a considerable time. It is inert, odorless, and colorless, which makes it extremely difficult to detect. Naturally, this gas is present in the atmosphere in trace amounts. While outdoors, it poses no health risks because it tends to disperse rapidly and our bodies adapt to its presence.

Radon gas can also be present inside workplaces, schools, and homes. It tends to slip through cracks and other holes in the foundation of a building and normally gets trapped in the basement. This is probably the reason most people assume it is an issue only experienced by homeowners with basements. When the gas is present in enclosed spaces, it tends to build up from normal levels to extremely high levels of radiation.

When exposed to radon gas for a while, you run the risk of developing lung cancer. In fact, it is considered the second leading cause of cancer in the United States. Fortunately, radon gas present in buildings can be controlled and managed with tried and tested cost-effective techniques. You can have your home tested by a professional or with a do-it-yourself home kit.

EPA guidelines suggest that radon levels should never exceed 148 Becquerels/meter3 (4 picocuries/liter). If the level exceeds, consider immediately contacting a certified radon service professional to increase your home air circulation or fix your underground ventilation system.

Radon Gas
Image Credit: Francesco Scatena, Shutterstock

divider 4 The 5 Causes of Radon in the Basement

1. Natural Stone Foundations

Many old homes were built on a foundation of natural elements like limestone, granite, and other quarry rocks. These natural rocks were combined with concrete or other building materials to make the building sturdier. Over time, certain rocks begin to decompose and erode, leading to the formation of radon gas.

One such natural stone with high trace elements of uranium is granite. So, if your home foundation contains granite, chances are high that it will decompose. Consequently, radon gas will slip into the basement of your building.

2. Soil

The soil outside your home is essentially made from twigs, trees, rocks, and decomposed animal matters, among other things. The topsoil layer tends to be tilled and delicate; however, as you go deeper, you will hit clay and rock sub-layers.

Therefore, when excavating the ground for your basement, you will have to dig through the hard rock formations, which will uncover soil with high concentrations of different chemical substances. When these elements decompose over time, they create radon gas.

Since basement floors are usually directly on top of these elements, radon gas will be able to sip through to your home due to the porous nature of concrete.

checking soil temperature
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3. Groundwater

When water doesn’t flow naturally, it will eventually get stagnant. In such a situation, a variety of biological organisms grow and die in the water, thus creating gasses. When the gasses combine with surrounding rock and soils, radon gas can be produced.

In deep basement environments, radon gas will begin to build up to a point where it needs to escape to the environment. Therefore, it will likely sip into the higher levels of your building as it looks for an outlet.

4. Rocks

Under any building, you will likely find large deposits of rocks that contain elements such as granite with trace amounts of uranium. When these rocks begin to erode due to the pressure exerted by the ground, radon gas can form.

As you would expect from any gas, the pressure will build up over time, needing to escape into the environment. The only place that radon gas can escape is upwards, which incidentally happens to be your basement floor.

construction of basement
Image Credit: Andrei Kholmov, Shutterstock

5. Cracks on Concrete Floors

It is important to inspect for cracks and holes on your floors regularly because concrete floors are not pliable, and they tend to crack over time. When the floor cracks, it creates an avenue for radon gas to sip through to your basement.

Fortunately, with mitigation systems and radon base detectors, you can reduce the amount of radon in your basement and protect your loved ones from its harmful effects.

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How to Determine the Radon Levels in Your Basement

To test for radon gas in your home, take short-term or long-term radon gas tests. Short-term tests usually last between 2 to 90 days, while long-term tests are longer than 90 days. Using radon detection equipment, start the short-term tests to determine the radon level in the lowest level of your home- the basement. This testing equipment can be bought from local hardware stores.

Alternatively, you could call a professional to do the testing for you.

If your short-term tests indicate that radon gas is close to 4 pCi/L, a long-term test is in order. This is because radon levels tend to fluctuate, so a long-term test will determine the actual radon levels. If the long-term tests determine that the radon levels are higher than 4 pCi/L, it’s time to employ mitigative measures.

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What Are the Signs of Radon Poisoning?

Now that you know what radon gas is and the causes, the next logical question is, what are the signs of high radon gas in your basement?

Well, there is no easy way to answer this question because there are no warning signs of the presence of radon. It is virtually impossible to detect radon with just the body’s senses.

It is colorless and odorless, meaning you can neither see nor smell it. It is tasteless so you cannot taste it in your tap water. Moreover, it doesn’t leave any discolorations, stains, marks, or evidence of its presence whatsoever. The only sure way of detecting its presence is testing, especially in the entryways.

Unfortunately, the only natural way of determining if your building has high levels of radon gas is by being diagnosed with cancer. Medical experts estimate that over 21,000 people die every year due to lung cancer induced by radon gas.

So, if you develop lung cancer and you’re not a smoker, chances are high that you have radon poisoning. It is even worse if you smoke because it amplifies your risks of developing the scary big C. Lung cancer usually occurs approximately 5 to 25 years after exposure.

The most common signs and symptoms of lung cancer due to radon exposure include:
  • Persistent cough
  • Chest pain
  • Unprecedented Weight Loss
  • Frequent lung infections, like bronchitis and pneumonia
  • Hoarseness in your voice
  • Wheezing
  • Shortness of breath
  • Loss of appetite
  • Fatigue

If you notice any of these cancer symptoms, you must consult your doctor as soon as possible. Even if it’s a false alarm, it’s better to be safe than sorry.

Fortunately, there is no evidence that radon gas causes other respiratory diseases such as asthma. Also, there is no evidence that children run a greater risk of radon-induced lung cancer than adults. However, most people only learn of the elevated levels of radon in their homes after a lung cancer diagnosis.

old and abandoned basement
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What to Do If You Have Radon in Your Basement?

After carrying out the radon tests and discovering dangerously high radon gas levels in your home, the next logical step is mitigation. Fortunately, there are several radon mitigation companies spread out throughout the United States that can easily install mitigation systems in your home or workplace to remove radon gas and make your basements safer.

If you are the more hands-on type of homeowner, you can also opt to reduce the radon levels by yourself using the following methods:

1. The Sub-Depressurization Method

This is the most commonly utilized radon mitigation system. The process basically involves inserting a suction pipe in the concrete slab line below the house through the floor. This suction pipe then draws out radon gas from the house vent and out into the atmosphere where it is less harmful to human beings.

2. Submembrane Depressurization

Though less common, the other radon mitigation method is known as submembrane depressurization. In this method, a plastic membrane seals the soil in the crawl space by wrapping it around the foundation walls. Then it uses the same ventilation method as sub-depressurization.

You could also opt to use a heat recovery ventilator. This is a simple machine that exchanges indoor and outdoor air to reduce the radon levels in your basement through dilution.

sump pump installed in a basement of a home
Image Credit: Jason Kolenda, Shutterstock

3. Natural Remedies

If you cannot afford radon mitigation systems, you could use natural remedies to reduce radon levels in your home. It may not be as effective as the machines but it would still work to reduce even the tiniest radon gas that you probably weren’t aware of.

The most basic natural remedy is increasing the ventilation of your home. You can simply do this by regularly opening vents, doors, and windows of your ground floor. The aeration will mix outdoor and indoor air, thus reducing the amount of radon gas in your home.

The only drawbacks to this natural remedy are the security issues involved with keeping all the entrances of your home for several hours on end. Also, once the doors and windows are locked, radon levels in the house will be back to normal in just 12 hours.

Additional Tips and Tricks:
  • To further reduce radon levels in your home. Consider replacing, sealing, or installing a sump well cover. This will close up the exposed area of the earth with direct access to your basement.
  • When experiencing extreme high and low temperatures, cool or heat your house as little as possible. This will reduce the pressure increase from drastic temperature changes, thus reducing the stack effect.

house divider Frequently Asked Questions

1. How Often Should One Test for Radon Gas Presence?

As aforementioned, the best way to fight radon gas exposure is early detection. The United States Environmental Protection Agency (EPA) recommends that you test your homes and workplaces after every two years. You should especially focus on the areas where low radon levels have been detected before. If unsure of your property’s radon level, you should consider doing the test immediately.

2. What Information Is Required By Radon Mitigation Companies?

Any company that specializes in radon abatement will often ask some fundamental questions to determine how best to tackle the radon issues.

These include questions such as:
  • When was your property built, and how was it laid out?
  • Does your property come with a basement or an underground crawlspace?
  • Does your property have any radon-resistant features?

3. Where Should One Place a Radon detector?

Most people would assume that the basement is the ideal place to install a radon detector. However, it is a good idea to place radon detectors in all the rooms and places within the household space. Do not determine the position you place your detector based on the level of usage of the household space or level of occupancy.

Radon gas can easily travel from the basement to other areas of the house. The concentration levels are not necessarily determined by the degree of ventilation or the general hygiene of a room. If anything, radon levels are likely to be higher in well-lit and ventilated rooms of the house.

house divider Conclusion

Radon gas is a part of the atmosphere and generally is not harmful. However, it can have adverse health effects if it accumulates in a poorly ventilated space.

Many people assume that radon is only present in the basement, but it can easily spread to all rooms in the house once it gets into your house from cracks and holes on the floor. When exposed to high levels of radon gas, you run the risk of developing lung cancer.

Since radon gas is virtually undetectable, the best way to determine the level is to carry out radon testing. The testing is inexpensive and fairly easy to do. Early detection is the best way to fight radon gasses in your home. Once you find that radon levels are dangerously high, you can use radon mitigation systems to reduce the levels. Regularly ventilating will also help reduce the levels.

Featured Image Credit: J.A. Dunbar, Shutterstock


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