graphic showing terrestrial radiation

Ecology: An Overview of Radon Levels as a Significant Source of Terrestrial Radiation

Radiation is a word that, quite justifiably, is associated with being something harmful and injurious to health. What if you were to find out that we are exposed to radiation all the time?

Radiation refers to the energy that is released by materials in the form of electromagnetic waves or particles. In this form, energy can travel at the speed of light through vacuums like space and other mediums.

Background radiation, which is essentially radiation that we’re exposed to at all times, has many sources. Most of us are familiar with the sources of radiation that are produced by humans. This is also known as a man-made source of radiation. This involves radiation emitted from medical, commercial and industrial procedures and products. For example, CT scans, x-rays, mammograms, radiation therapy, etc., electronic devices like cell phones, televisions, radios, microwave ovens, etc., the use of nuclear power or coal to generate electricity and nuclear weapon tests, among many more sources. Radiation emitted from these sources, however, only constitutes 12% of all the background radiation exposed to us.

The majority of the radiation that we’re exposed to comes from natural sources. An example of this is cosmic radiation, the radiation that we receive from space. Cosmic radiation is produced when particles from celestial objects interact with the Earth’s atmosphere. Another example is the radiation we expose to others because of the naturally occurring radioactive isotopes of certain elements found in the human body – potassium-40 and carbon-14.

The major source of natural radiation, however, is terrestrial radiation. Terrestrial radiation refers to the amount of background radiation emitted naturally through the ground, soil and water. This is due to the presence and decay of radioactive materials that occur naturally within the Earth’s crust. These radioactive elements decay over time and their products, which are also radioactive, are found everywhere.

One of these products is radon, which is the topic of discussion for today. In this post, we will learn about what radon is, how and why exactly it occurs, where it occurs, how its presence impacts human lives, and how to mitigate any threat it poses.

What is Radon?

Symbol of Radon as seen in the periodic table
Image Credit: Thoughtco

Radon is the largest source of natural background radiation that we’re exposed to all the time. Most often, we do not even realize it exists. But what is it exactly?

Radon is an odourless, colourless, tasteless, non-flammable but highly radioactive gas. It occurs naturally and is present in the atmosphere for two main reasons – terrestrial radiation and human activities like burning fossil fuels such as natural gas and coal, and mining.

Radon is one of the six inert or noble gases known to exist. Being a noble gas means that it does not react with other chemical substances. Hence, it doesn’t form any chemical compounds. However, unlike the other inert gases, radon and its isotopes are unstable, making it radioactive. Due to this instability, it spontaneously releases energy or particles in the form of radiation and disintegrates into various other unstable elements before finally reaching its most stable form. The product that it decays into is known as a daughter product. This whole process is known as radioactive decay. In the case of radon, it emits alpha particles and decays into radioactive isotopes of bismuth, lead and polonium.

Where does Radon come from?

Earlier in this post, it was mentioned that the Earth’s crust contains naturally occurring radioactive materials. The radiation emitted due to the decay of these materials is what causes terrestrial radiation. These materials are actually radionuclides or unstable forms of elements that emit radiation. Uranium, thorium and radium are some radionuclides that are present in very small amounts in all rocks and soils on the planet.

Like radionuclides, they also undergo radioactive decay, and it is through this process that radon is formed. In fact, radon is a daughter product of one of the isotopes of radium, which is a daughter product of an isotope of thorium, which in turn is a daughter product of the most abundant isotope of uranium found in nature – Uranium-238.

The reason radionuclides like uranium and thorium naturally exist in the Earth’s crust is because they are actually the remnants of the Big Bang; ancient supernovae that occurred long before the solar system was formed, and remnants of other cosmogenic sources. This is why they are even known as primordial radionuclides. They still exist today because of their incredibly long half-lives.

A half-life is the amount of time taken for half of the unstable atoms in an element to decay. Some elements may have a half-life of a few seconds, while others have a half-life of billions of years. Uranium, for instance, has a half-life of 4.5 billion years, while radon has a half-life of 3.8 days.

Radon gas is also released when burning fossil fuels because, after all, are obtained from the Earth’s crust, where radon gas is abundant. The gas is also emitted through construction materials such as bricks, granite, concrete, etc. as they also contain trace amounts of uranium.

The Journey of Radon Gas from Soil to Air

Unlike its parents – uranium, thorium and radium, radon is a gas. Being a gas means that it has much better mobility than its parents, which are all solids and metals. It is able to manoeuvre itself from the depths of the ground up to the surface through the pores, gaps and cracks underground.

To reach the surface, however, radon gas must travel through various layers of thick rock and soil. So, the characteristics of these rocks and soils determine their speed and mobility.

If they are too dense, have low permeability or have too much moisture, it becomes difficult for the gas to escape. As such, it is trapped and disintegrates before finding a way out. Only 1/1000th of the radon present in the sub-soil manages to come up to the surface.

It is easier for radon to escape through gravel, coarse sand, and silt due to its high permeability. On the other hand, it is difficult to seep out through clay, as it is less permeable and it retains water. Radon moves slower through water.

The actual amount of radon released from a certain location depends on the concentration of primordial radionuclides present in the rocks and soils in the area. The amount, therefore, varies from place to place. The amount will also change over time due to radioactive decay. Radiation emitted in the same location could be different at another time period.

Consequently, national agencies in different countries around the world have created maps to indicate the locations with higher concentrations of radon. In the United States, for instance, the Environmental Protection Agency (EPA) has designed the following map:

Map of Radon Zones in the U.S.
Map of Radon Zones in the U.S. Image Credit: EBI Consulting

What happens to Radon once it reaches the surface?

Once the gas seeps out from the ground and reaches the surface, it begins to decay and produces its daughter products and emits alpha particles, and secondly, it mixes with the ambient air. Upon mixing, it disperses from high concentration areas to areas with lower concentrations of radon.

According to the World Health Organization (WHO), the average level of radon found outdoors ranges from 5 Bq/m3 to 15 Bq/m3  or 0.135-0.405 pCi/L.  These measurements are discussed in detail further in the article.

The concentration of radon present outdoors, not only depends on the amount of primordial radionuclides found in the ground in that area but, also on the weather conditions there. This is because it influences the mixing of air. For instance, the concentration of radon outdoors will be lower if there is rain, snow cover, an increase in air pressure, etc. On the other hand, it will increase with an increase in wind and temperature.

Radon Gas in our Homes and Other Indoor Spaces

Radon, being a gas, disperses in the atmosphere from where some of it enters and gets trapped inside buildings and indoor spaces. Another way that the gas enters into buildings is directly through the ground.

What happens is that the radon gas that rises up into the soil from the depths of the Earth’s crust gets trapped under buildings. Trapping this gas builds high pressure. Generally, the air pressure inside buildings is lower than the pressure underground because of heating, air conditioning and ventilation systems that allow indoor and outdoor air to mix.

Due to the differences in these pressures, the high pressure built underneath the building forces the gas inside the structure through any gaps, cracks, pores or openings it comes across. Once it enters the building, the gas is trapped and it starts to build up in large concentrations.

The level of radon is highest in indoor spaces that are closest to the ground. This is why there are often increased concentrations of radon in underground spaces, like caves, mines, basements, etc.

There is often a misconception that only older worn-out buildings have increased radon levels, since they tend to have more broken or cracked walls, floors, holes, gaps, etc. Or that lower levels of a building have higher radon levels. In reality, all indoor spaces, including homes, offices and schools, whether they’re old or new, are all exposed to some amount of radon gas of varying concentrations. The gas even leaks into the higher floors the same way that it enters the building in the first place. Albeit, the concentrations of radon are lower at the upper levels.

sources of radon gas emission
Sources of radon gas. Image Credit: CT Radon

Factors Determining Concentration of Radon Indoors

Some of the factors that influence these concentrations indoors are the amount of primordial radionuclides present in the area, the distance of the indoor space from the source of radon gas; the difference in air pressure between the ground and the building. If the difference is large, the concentration of the gas is likely to be higher. Other factors are the number of fissures present in the foundation of the building, and the number of paths for gas to enter from below the ground. This may be in the form of cracks, holes, pores, cavities, drains, sumps and gaps around loosely fitted pipes or cables.

Additionally, certain features within buildings, such as the basement, cellar or crawl space, being so close to the ground, maybe constructed using permeable materials like loose gravel or coarse sand. This would facilitate the escape of radon gas into the building and atmosphere. Lastly, the concentration of radon will be higher if there is overall poor ventilation in the building as it contributes to trapping the gas. In fact, it is this trapping and deposition of radon that indoor levels of radon are sometimes more concentrated than the radon directly being released from the ground.

According to the EPA, the average level of radon found indoors in the United States is 1.3 pCi/L or, 48 Bq/m3. 

Presence of Radon in Water

Radon is not only present in the air and ground but also water. Including the water that is supplied to our homes. Radon tends to dissolve in water and release itself into the air when the water is agitated.

Water supply systems use either groundwater or surface water. Water supply in buildings is another source for radon to enter and be part of the air indoors. Radon is released into the air when the water is used for household activities. Both types of water sources contain radon but in varying concentrations.

Surface water such as reservoirs, lakes and rivers contain lower levels of radon as much of the radon is released into the air before it is supplied into homes. Only trace amounts remain in the water. In urban areas, where water from various sources goes through water treatment plants, also contain lower concentrations of dissolved radon gas, as one of the steps in the treatment process is aeration. This process agitates the water thus, releasing the radon into the air.

In places that don’t use surface water or treated water, they use groundwater. Rural areas, in particular, still make use of groundwater obtained from wells, springs and boreholes. This water is then used to drink, wash clothes, cook, wash utensils, bathe and basically carry out necessary household activities.

Groundwater contains larger concentrations of radon gas because it has more direct contact with the rocks and soil containing small amounts of uranium and thorium for prolonged periods. The concentration is even higher in groundwater that passes through areas known to have rocks containing higher levels of uranium. When this water is used for daily activities, radon gas is released indoors, where it gets trapped.

On average, water containing 10,000 pCi/L of radon will add to 1 pCi/L of radon indoors.

How does Radon enter the human body?

Now that we know how we come in contact with Radon, let us see what happens when we’re exposed to it.

The radon that is released from the soil and water combines with the ambient air. This is the same air that we breathe in. Consequently, we inhale a certain amount of radon every time we breathe. The amount of radon inhaled increases as the concentration of the radioactive gas increases. Meaning, we inhale more radon when we are indoors. Inhalation is the primary method through which radon enters the human body.

The gas also enters the human body when a person ingests drinking water containing dissolved radon, or by consuming foods with traces of radon.

What happens once we’re exposed to Radon?

Radiation is a natural process that has been since the beginning of time. Our bodies are designed in a way that is able to tolerate being exposed to very low levels of radiation. Or at least being exposed without posing any major health risks. Besides, not all types of radiation are harmful. It is only the ionizing radiation that we must watch out for. Some radiation particles are known to damage living tissues to the point that they are irreparable, causing cancer, premature ageing and increasing the threat of developing heart diseases, strokes, respiratory and digestive diseases.

Unfortunately, in the case of the omnipresent radon, it emits ionizing alpha particles during its decay process.

This radiation emitted from radon gas has been proven to put people at a higher risk of developing lung cancer. In fact, radon is one of the major causes of lung cancer in the world. According to WHO, it is responsible for 3%-14% of all lung cancers in a country, and according to the EPA, radon is the second major cause of cancer overall, after cigarette smoking.

In the United States alone, around 20,000-21,000 people die annually due to radon-induced lung cancer.

The risk of developing lung cancer from radon really depends on the dose of radon an individual is exposed to, how the radioactive gas enters the body and whether or not the individual is a smoker.

Concentration of Radon

The average concentration of radon present outdoors in the atmosphere is minimal. So, it isn’t enough to cause any major health issues. The problem arises when individuals are exposed to high concentrations of radon for extended periods of time. Though the effects aren’t visible in the short term, in the long term, the exposure is often responsible for the development of lung cancer.

They may even be victims of radon poisoning, which damages the body gradually and its symptoms take years to appear. When they do, it is often near the time when a person develops cancer or when they’ve already developed it. Some symptoms of radon poisoning are shortness of breath, coughing, wheezing, chest pain, frequent occurrences of pulmonary infections like bronchitis or pneumonia, fatigue, weight loss, etc.

In this case, an extremely high amount of radiation from radon is exposed to the human body within a short amount of time; it may result in a serious radiation emergency or even death.

As we discussed earlier, high concentrations of radon can be found in indoor spaces, especially in spaces close to the ground, with a lot of entry points for the gas to enter and where there is poor ventilation. Therefore, risks of developing health issues can be high in everyday spaces such as homes, offices and schools with high radon levels. These are after the places that we spend most of our time in. However, individuals working in mines, caves, other underground spaces, uranium processing units, etc. are exposed to the largest amounts of radon.

This increases their risk of developing a major health issue like lung cancer. The reason why we now know that increased concentrations of radon increase the risk of lung cancer is because of scientific studies done on miners in the mid-20th century.

Entry through Inhalation

diagram showing how radon damges living cells
The consequence of inhaling radon. Image Credit: Interior Health

Most of the radon found in these places is inhaled, which is the worst way for radon to enter the body. This is because maximum radiation exposure comes from inhaling radon present indoors and in the water supply.

Once an individual breathes in a certain amount of radon, the gas enters the lungs, where it begins to decay. Once the gas begins to break down, it emits ionizing alpha radiation particles and their radioactive decay products.

Now, unlike radon, its decay products are solid in nature. Also, unlike radon, they aren’t noble gases, which means that they are electronically charged and are able to attach themselves to other particles in the air that are inhaled, like dust. Due to these properties, the daughter products also deposit themselves in the lining of the lungs. Once they stick to the surface, the radioactive products also begin to decay, breaking down into their unstable daughter products and further emitting ionizing radiation particles.

Meanwhile, the original alpha particles emitted during the radioactive decay of radon are at work.  Alpha particles cannot penetrate into human skin. However, if it is inhaled or ingested, it can damage living tissues, cell structures and DNA. These tissues are damaged to the point that it is difficult for the cells to repair themselves without making errors. These errors ultimately lead to cancer.  This is what happens to the tissues in the lungs.

Once radon enters the lungs and starts to decay, it travels very short distances. Meaning, much of the damage is restricted to the lungs as it doesn’t go far enough to harm other tissues. This is how the lung becomes the target of radiation from radon.

Other Methods of the Gas Entering the Body and their Risks

Radon dissolves in substances like fat and water. And, we discovered earlier, that water sources, particularly groundwater, also contain radon. While most of it is either inhaled or diffused into the atmosphere, some of it is ingested. This ingested water is absorbed by the stomach and intestines, which is where it most likely begins to decay. Although there isn’t sufficient evidence to support this, some scholars believe that ingesting radon increases the risk of stomach cancer. It is known that the threat of cancer is higher when radon is inhaled as compared to ingested.

Apart from water, even construction materials used to build homes also contain radon. Luckily, the amount of radon released from these materials does not contribute much to any major health issues.

While there is a risk of lung cancer for everyone, the risk is elevated for those who smoke regularly. More than 85% of lung cancers caused due to radon were found in smokers. The risk multiplies further if these individuals also reside in an area concentrated with radon.

What is the Safest Level of Radon?

The safest amount of radon exposure would be 0, but realistically speaking, achieving this level is impossible. Radon is, after all, everywhere.

So what is the most acceptable level of radon that we can tolerate without risking our health? This varies from country to country. But before we discuss the standard levels advised by national and international agencies, let us understand how radioactivity is measured.

Two units are largely used to measure radioactivity or the amount of radiation emitted from a radionuclide like radon. They are, Curie (Ci) and Becquerel (Bq).

To measure the speed of decay, the standard measurement used worldwide is Bq/ m3. The United States, however, uses pCi/L.

Bq/m3 stands for Becquerel per cubic metre.  This measures the amount of radon in every cubic metre of air.  Here, 1 Bq = 1 radioactive decay per second

1 Ci = 3.7 x 1010 decays per second. This refers to the amount of radioactive decay that happens in 1 gram of radium every second.

1 pCi = 1 trillionth of a Curie.

pCi/L stands for Picocuries per litre. It measures how fast radon decays by calculating the number of picocuries of radon present in every litre of air.

1 Ci = 37 billion Bq

1 pCi/L = 37 Bq/m3

According to WHO, the average amount of radon that should motivate taking action to reduce radon levels is 100 Bq/m3. In places or situations where it isn’t possible to attain this level, it is advised not to exceed 300 Bq/m3.

In the United States, for instance, the EPA recommends maintaining indoor radon levels between 2 and 4 pCi/L (74 and 148 Bq/m3) and it requires water suppliers to supply water that does not exceed 4,000 pCi/L (148,000 Bq/m3) as it releases 0.4 pCi/L (14 Bq/m3) of radon indoors.

arrow indicating acceptable radon levels
Action levels as recommended by WHO and EPA. The concentrations are measured in pCi/L. Image Credit: Rad Tek

Solutions to deal with Radon Gas

So far, we learned that the lower the radon levels, especially in indoor spaces, the better it is for our health. Fortunately, radon levels in buildings can be reduced. With the methods and systems that exist today, it is possible to reduce the levels by over 50%. That too for affordable prices.

Before all, however, it is important to know how much risk we’re at. Notably, in places where we spend most of our time, like our homes. This is done by testing radon levels in indoor spaces and checking if radon levels meet the regional acceptable amounts.

When moving into a new home, it is always a good idea to test the radon levels of the space. That is, in addition to making sure that the place has some sort of radon mitigation system. When constructing a new home or building, it is another great idea to add at least one of many radon-resistant features. Ensuring reduced levels of radon at all times.

Importance of Testing

Radon, being an odourless and colourless gas, cannot be felt or seen. So, the only way to detect radon levels is through special devices and testing kits.

Once the test is completed, it will help determine whether the radon levels are within advisable levels. If it isn’t within the acceptable range, it is best to take action to reduce these levels. There are several ways to solve the issue but, many individuals prefer to invest in a radon-reduction system for their properties. These systems work by either reducing radon before it even enters the building or by removing it after it is trapped indoors. There are also systems to reduce the amount of radon gas from water supply systems as well. Such systems a long term, reliable and affordable to a problem that exists all the time. Anyone is capable of installing these systems with little knowledge and training. However, most prefer hiring radon mitigation contractors.

Let us now explore radon testing devices and a few of the mitigation systems, in detail.

Radon Testing

image of a radon testing kit
A short term radon testing kit. Image Credit: Pro Lab Store

It is important to detect radon concentrations indoors as it allows us to understand the level of risk we are really at. Understanding the risk will also determine what sort of reduction system is best for the building. What is interesting is that all buildings have different levels of radon. Even if they are located in the same neighbourhood, or even if they stand next to each other.

This happens because of the characteristics of the soil underneath the building. One building could be standing right under the soil that may have numerous fissures, allowing radon to escape. Another reason for this occurrence is that the number of cracks, gaps and holes always vary in different buildings. Lastly, the amount of ventilation also contributes to the differing levels of radon indoors. This is why the test must be done individually for each building, instead of testing just one building in a certain area.

Radon detection is done by placing small devices inside the home and the radon levels are either analysed in a lab or by the device itself. The test can be simple enough to do on your own. These tests usually come in the form of a kit along with a set of instructions. Once the test is done, the kit is sent to a lab for the results. These kits are available online or at certain hardware stores. In the U.S., radon testing kits cost between $15 and 30. On the contrary, tests can be complex enough to require the professional services of radon inspectors. These do not usually need to be sent to a lab for reports.  These tests range between $120-400. 

Types of Tests

Testing devices can be of two types – active or passive. Passive tests do not require the use of power, tend to be inexpensive and the tests can usually be done without the help of a professional. Passive tests include detection devices like alpha-track detectors and charcoal liquid scintillation devices.

a device used to detect radon
An Alpha-Track Detector. Image Credit: RGC Radon

An alpha track detector, for example, uses a chip to detect alpha particles. Usually, when alpha particles are emitted during radon decay, they collide with other materials in their surroundings. In the process, they leave their track and the chip detects it. The information from the chip is used to count the number of tracks and used to calculate the amount of radon required to create those number of tracks.

Active testing devices make use of power to work. They are also costlier than passive devices but they are able to provide hourly readings of radon levels. Some not only measure but record, analyse and even prepare reports based on those measurements. Active testing devices are more complex to operate, so it often involves a professional. Some types of active devices are continuous radon monitors and continuous working level monitors.

A continuous radon monitor, for example, works by either collecting a portion of air through a small pump or by letting air directly enter its sensor chamber. The device then continuously measures the amount of radon and its decay products in the air. For maximum accuracy, the machine needs to be calibrated frequently.

continuous radon monitoring device
A continuous radon monitor. Image Credit: Femto tech

Short-term and Long-term Testing

These detectors are available for both short term and long term tests. For short-term tests, the detector is kept indoors between 2 and 90 days. They quickly provide an understanding of the radon levels present. Short-term tests are usually done for urgent cases such as when a person wishes to sell their home or if they wish to check if their radon reduction system is properly functioning.

Some people doubt the accuracy of these tests, so they do them more than once. Alternatively, they opt to do long-term tests. For this type of testing, the device is placed indoors for 90 days or more. Long term tests seem to be more reliable because they provide detailed information about the average annual concentration of radon found indoors. Radon levels tend to fluctuate, not only throughout the year but throughout the day as well, within the same building. So, this sort of testing provides more accurate results and helps determine which reduction system would be best.

As we discussed earlier, acceptable levels of radon indoors depend on a country’s regulations. If the levels are found to be higher than the acceptable amount after testing, a reduction system is installed.

Radon Mitigation Systems

Radon mitigation systems refer to systems implemented to reduce the level of radon gas within buildings. These systems have been designed based on scientific research and professional experience.

Radon mitigation systems available today are efficient, capable of even reducing extremely high concentrations of radon. They are reliable and durable, as they last for at least 10-15 years. And the best part is that they are affordable.

There are generally two ways to reduce the concentration of the radioactive gas. The first is to prevent radon from even entering the building. The second method is to remove the gas after it enters the indoor space. The EPA, recommends the first method because prevention is always better than cure.

Active Mitigation Systems

Radon mitigation systems can also be classified as either active or passive.

Active radon mitigation systems are typically installed when buildings have really high concentrations of radon. This system makes use of continuously running vent fans and pipes to draw the radon out from indoor spaces with high levels of radon, and release it outdoors.

The pipe, which is installed either indoors or on exterior walls, runs from the lowest levels of the building, like the basement, to the roof or attic. This is where the vent fan is located.

This system is best to drastically reduce radon levels. Being a durable and reliable option, many people prefer this system to the passive system.

Active Soil Depressurization is perhaps the most popular active mitigation system installed. In this system, pipes are installed inside the building, such as in places like the basement or garage. Air is drawn out from the soil and expelled outside the house using a vent fan on the roof. In case there is no underground space in the building, a hole big enough to fit a PVC pipe will be drilled onto the ground in the concrete slab. Once it is attached, it runs along the building to be fitted with a fan.

diagram of an active soil depressurization system
A typical active soil depressurization system. Image Credit: M. Webster Construction Inc.

Passive Mitigation Systems

Passive radon mitigation systems are installed during the construction of a building. Unlike the active reduction system, it doesn’t require the use of electricity. Instead, it takes advantage of the differences in air pressure between the soil and buildings, and the air currents to reduce levels of radon.  The pressure is what allows the gas to move through the pipes to the exhaust vents.

An example of this system is the use of radon barrier membranes. These are large multi-layered plastic sheets that are spread on the ground during construction. It is part of the building’s foundation. The membrane is meant to prevent the radon from escaping from the ground and entering the building.

red radon barrier membrane to prevent radiation
Radon barrier membrane being spread on the ground. Image Credit: Laydex

This system is generally better for places with moderate to low levels of radon. As it is better at maintaining these levels rather than actually reducing them.

One advantage of this system is that it is built into the structure so it is out of sight. It doesn’t have any pipes running down the walls. However, as it is installed during building construction, most of the time it isn’t installed by experts like radon mitigation contractors. As a result, the system often isn’t installed properly because of which, it doesn’t function as intended. Unfortunately, building owners or residents aren’t always aware of this, so they falsely believe that they are protected. When, in reality, it is doing absolutely nothing. For this reason, among many others, people prefer to convert it to an active system by adding a vent fan.

Once these systems are installed, another radon test is often done to check their efficiency and efficacy.

Selecting the Right System

Selecting the best radon mitigation system depends on the needs of the building. These are based on a few factors. The first is, of course, the geology of the location, the second is the concentration of radon present indoors. This is based on the radon detection test. Next, is the size and design of the structure, including the foundations. Lastly, it depends on one’s ability to afford these systems, their installation and maintenance costs. Considering all these factors, it is possible to select the ideal system or even design a customized system. This can be done with a help of a radon mitigation contractor.

Other Mitigation Systems

Just as there are systems to mitigate radon levels released from the ground, there are also systems to treat radon in water supply systems. This is done by either removing radon from the water before it enters the water supply system, by using filtration or aeration systems. Or by removing radon from water when it reaches the tap. The latter is better to prevent ingesting radon but, the former is better for preventing inhaling radon from water.

Other methods to reduce radon levels are relatively simpler and can easily be done without professional help. It involves sealing off all entry points, especially the cracks and gaps in underground spaces. This can be done using rubber seals or caulking products like latex and silicone. It also involves increasing ventilation by opening windows and adjusting air vents to allow better passage of air within the building. These methods, however, aren’t very durable or effective on their own. If they are done in addition to installing a radon abatement system, it will ensure maximum reduction.


radon mitigation contractor installing system
Contractor at work. Image Credit: Radon Resources

As mentioned earlier, these systems can be installed by anyone with a little bit of training and knowledge. However, many find it a hassle to get this training and they attempt to install the systems without it. As a result, many mistakes are made in the process. The fixtures aren’t installed properly, leaving gaps and holes and thus, increasing radon concentrations. It ultimately leads to wasting time, money and energy.

As such, numerous people directly engage radon contractors or mitigation services. A qualified contractor will have the expertise, knowledge, skill and resources to solve all radon related issues. They can do the testing, advise on the appropriate radon reduction system and install it properly and in the safest way possible. Ensuring not to increase any gaps or cracks in the process, cause any other potential risks or involve any extra costs. Moreover, with contractors involved, the systems can be installed within a day.

Naturally, most homeowners like to hire qualified and certified contractors, ones that can guarantee to fix the problem.

Costs and Maintenance

The average cost of the system depends on the type of system. Typically, active radon mitigation systems tend to cost slightly more as they make use of electricity to constantly power the vent fans. Fortunately, they are low voltage fans, so the increase in cost isn’t drastic.

It also depends on the size, design and foundation of the building, along with the construction materials used to build it. It is also determined by the weather of the location that the system is being installed. In the U.S. the average cost of a radon-reduction system can range from $1500 to $3000.

There may be some added maintenance costs too, as some of the equipment needs to be cleaned or replaced every few years. Equipment such as vent fans and filters in the systems that require filters.

A Quick Recap

graphic of the radiation symbol inside a house inside a triangle
Image Credit: KFL&A

In summary, radiation is a natural process that is released by materials in the form of electromagnetic waves or particles. We are constantly exposed to natural background radiation, of which terrestrial radiation is the largest source. Terrestrial radiation is emitted due to the decay of naturally occurring radionuclides like uranium in the Earth’s crust. One of the products of uranium decay is radon, a highly radioactive and carcinogenic gas. Inhaling radon happens to be the second major cause of lung cancer. The majority of radon is released from the ground. And the majority of it is inhaled in indoor spaces, where the gas gets trapped.

Every country has its own acceptable levels of radon before action is recommended. While it is impossible to remove all radon from indoor spaces, it is possible to reduce it. Reduction starts with testing to understand the risks, then radon abatement systems are installed. Most of the time, it is installed with the help of radon mitigation contractors.

Much is still unknown about radon so, until it is further studied, the objective is to keep indoor radon levels as low as possible.

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Missimer, T. M. et al., 2019. Natural Radiation in the Rocks, Soils, and Groundwater of Southern Florida with a Discussion on Potential Health Impacts. International Journal of Environmental Research and Public Health, 1793(10), p. 1.

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  1. I loved it when you mentioned that every country has its own acceptable levels of radon before action is recommended. We just bought a house near the beach. I want it checked for radon gases to make sure we are safe from hazardous gas. Thank you for this guide on how and where to find radon mitigation services in town. I will be looking for one tomorrow.

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