Whether you’ve been in your home for years or are just about to close on a new home, it’s important to have it tested for radon and know what to do if you get an elevated result.
Radon is a naturally occurring, radioactive gas that’s formed from the natural breakdown of uranium in soil, rocks, and water. Low levels of uranium occur naturally in the Earth’s crust and can be found in all 50 states. It has no color, odor, or taste, so unless you test for it there is no way of knowing the amount present.
Most indoor radon comes from the soil or rock beneath buildings. Air pressure inside your home is usually lower than pressure in the soil around your foundation. Because of the pressure difference, your home acts like a vacuum, drawing radon in through cracks in floors or walls, construction joints, or gaps in foundations around pipes, wires, or pumps. Radon levels are usually highest in the basement or crawl space. Once inside, the radon can become trapped and concentrated.
So why be concerned? To put the potential danger of radon in perspective, Jerome Adams, U.S. Surgeon General, has identified radon as the second leading cause of lung cancer in the United States. Only smoking causes more lung cancer deaths.
Radon gas decays into radioactive particles that can get trapped in your lungs when you breathe. As they decay, these particles release small bursts of energy that can damage lung tissue and lead to cancer over the course of your lifetime. The Environmental Protection Agency (EPA) estimates that radon is responsible for 21,000 lung cancer deaths every year.
New and old homes, well-sealed and drafty homes, and homes with or without basements can all have radon problems. That’s why it is critical that all homeowners have their homes tested.
When it comes to radon testing, homeowners have two different options.
One option is to purchase a single-use “do-it-yourself” test kit. Simple to use and relatively inexpensive, these kits can be found in hardware stores, local health departments and county extension offices.
When you are buying or selling a home, however, the EPA recommends that you hire a certified radon mitigation contractor to conduct the test.
Testing is done in the lowest occupied level of the home or in a regularly used room. During the test, all windows and doors must remain closed to ensure accurate results.
Radon is measured in picocuries per liter of air (pCi/L). A pCi is a measure of radioactive decay. According to the EPA, radon levels of 4 pCi/L or higher warrant immediate action to address the issue in your home.
What happens if you’ve found high levels of radon in your home? First, don’t panic. Radon is everywhere and fixing a radon problem is relatively straightforward. One out of every 15 homes in the U.S. has a radon problem.
The cost of radon mitigation systems is influenced by several factors, including the size and design of your home.
There are several methods a contractor can use to lower radon levels in your home. Some techniques prevent radon from entering your home while others reduce levels after radon has entered. Homes are generally categorized according to their foundation design.
In homes that have a basement of a slab-on-grade foundation, radon is usually reduced by one of four types of soil suction: subslab depressurization, drain-tile suction, sump-hole suction, or block-wall suction.
Active subslab depressurization is the most common and reliable radon reduction method. One or more suction pipes are inserted through the floor slab into the crushed rock or soil underneath. A radon vent fan is then connected to the suction pipes and draws radon gas from below the home and releases it into the outdoor air while simultaneously creating a negative pressure or vacuum beneath the slab.
Drain tile suction directs water away from the foundation of the home. Sump-hole suction is used in homes with a basement that have a sump pump to remove unwanted water. The sump can be capped so it can continue draining water and serve as the location for a radon suction pipe. Block-wall suction removes radon and depressurizes the block foundation wall.
In crawlspace homes, submembrane suction is an effective method. This involves covering the earth floor with a high density plastic sheet. A vent pipe and fan are then used to draw the radon from under the sheet and vent it to the outdoors.
Regardless of the mitigation method you choose, today’s technology can usually reduce radon levels in homes to 2 pCi/L or below. The EPA recommends homeowners re-test for radon every two years.
While discovering high radon levels in your home can be upsetting, it is an easily resolved issue.