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What is Radon?

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What is Radon?
by: Joshua Luttmer

Radon is an odorless, colorless, radioactive gas that is harmful for your health. Radon gas is all around us all of the time, but inside your home Radon can accumulate to potentially harmful levels. To understand what Radon is, we must first understand where it comes from.

Where does Radon gas come from?

Radon gas is a radioactive decay product of Uranium U-238, which is ubiquitous in soil across the world. Uranium is the stuff that atomic bombs are made of. And we all know how radioactive materials are harmful for our health from watching movies and reading books, right?

So how does Uranium in the ground produce Radon gas? Well, it all has to do with how radioactive elements decay. Uranium U-238 has a half-life of approximately 4.5 billion years. Since the earth was formed around 4.5 billion years ago, that means that around half of the Uranium in the earth's rocks and soils has already decayed. When Uranium-238 decays, it transforms into Thorium-234, which decays into Protactinium-234, which decays to another from of Uranium U-234, this decays to Thorium-230, which decays to Radium R-226, and finally we get to Radon-222. Here is where it becomes a gas. So Radon-222 only has a half-life of 3.8 days. Because of this it can only travel so far. But, there is plenty of it emanating out of the ground and into our homes and businesses. Radon isn't the real threat here though either. It's actually the decay products of Radon that pose the true risk to our health.

You see, the radioactive decay products from Radon have even shorter half-lives. Some as short as a few seconds. You might be asking yourself why that matters though, right? Well, each time a radioactive element decays, it is releasing alpha particles, beta particles or gamma rays. Alpha particles are the most dangerous when it comes to Radon decay. Thats because alpha particles are not able to travel very far, and they are relatively easily stopped. As sheet of paper could stop an alpha particle in its tracks. But when an alpha particle stops, it releases is radioactive energy which can damage whatever it is touching as it decays yet again.

Is Radon gas harmful?

When a person inhales Radon gas, some of that gas decays inside of our lungs. Since the particles that are produced by Radon decay have half-lives that are seconds or less, those particles are releasing their energy inside of our delicate tissues, causing DNA damage in the process. And that is why Radon gas is so harmful to our health. Radon is the second leading cause of lung cancer in the United States, with around 20,000 lung cancer deaths per year.

What can I do about Radon in my home?

The good news is that Radon gas levels can be reduced inside your home. You see, because Radon is a gas is can only enter though vulnerable areas.  It cannot pass through solid materials, just like you or I cannot. Radon mitigation includes sealing cracks in your foundation, walls, windows and doors on the lower levels as well as reducing the pressure differential between the interior of your home and the soil. An active Radon mitigation system actually creates a vacuum below your homes foundation to suck the gas right out from under your home and expel it above your roof line! So, you see its not all doom and gloom when it comes to Radon gas. But the only way to know if you have a Radon problem in your home is to get it tested. If you don't already have a Radon mitigation system, it is recommended that you have your home tested every 5 years to check if Radon levels are crossing the action level of 4 pCi/L. If you do have a mitigation system, you should test every 2 years to be sure that the system is still performing well enough to reduce levels below the action level.  Additionally, it is recommended that a home be tested every time a new resident moves in.

How do you test for Radon gas?

The test process is fairly simple. A certified technician will place a device (or pair of devices) on the lowest occupied or conditioned level of your home for a period no shorter than 48 hours. If the device is an active continuous radon monitor, then your test results will be available within 24 hours from the end of testing. However, if the technician uses a passive test kit such as an activated charcoal test kit, it will need to be analyzed by a laboratory before the result will be made available. Caliber Inspections uses state of the art SunRadon Model 1028-xp continuous radon monitors, so we can get your results to you as quickly as possible. Should the test result be above the 4 pCi/L action level, a second test can be performed to verify the original result. Should that test be above action levels, it is highly recommended that mitigation efforts take place, but ultimately that decision is up to you.

In conclusion, Radon is a harmful gas that is in all of our homes. It is formed as a radioactive decay product of the element Uranium-238. Radon gas decay produces alpha particles in our lungs when the gas is inhaled. But, we can mitigate the risks of Radon gas by having our homes tested for it and installing a mitigation system if the exposure levels are above the action level of 4 pCi/L.

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