Radon in Winter
As we enter the coldest season of the year, be aware that the cold temperatures increase the pressure within the home, which pulls more air up and in from the ground (see How Radon Gets Into the Home below). This phenomenon increases the chance of radon entering the home. Normally radon levels are naturally affected by the changing seasons, atmospheric pressure (which put pressure on the soil around the home), and rain throughout the year. However, temperature fluctuations have the greatest impact on indoor radon levels due to the differences in pressure put on the home, causing the home to bring more air in from below. It is actually better to test for radon during winter months to see what the highest possible potential radon is overall.
What is Radon?
Radon is an odorless, radioactive gas that is naturally occurring and usually enters the home from unseen or smelled vapors rising from the soil beneath the foundation, coming in through ventilation systems, cracks and other openings. It is created from the breakdown of natural deposits of Uranium, which breaks down to Radium, which then turns into Radon Gas which is damaging to the lung tissue.
Radon (Rn) has an atomic number of 86 and a mass of 222. It is measured in Pico Curies per liter of air, named after Marie Curie, the pioneer physicist in the late 1800’s who discovered Radioactivity, Polonium and Radium. The Environmental Protection Agency (EPA) has deemed Radon a Group-A Carcinogen, alongside Arsenic, Asbestos, Benzine and Vinyl Chloride.
How Does Radon Get Into the Home?
Radon enters from beneath the building’s foundation and travels upward into the building due to vacuum pressures created by the building’s heating, ventilation and air conditioning units.
Imagine a house breathing, expanding and contracting based on the air flow conditions, pulling the gases from the ground up into the home. This movement of vacuum is not visible to the naked eye. Wind and weather can also affect this vacuum.
When the radon is breathed into the lungs, the radon decay products (which are microscopic) release radioactive alpha particles that then can damage your sensitive lung tissue and the DNA within the cells.
Health and Radon: Why is Radon Testing Important?
Radon is known to cause lung cancer with cumulative exposure, especially for smokers, causing 15,000-22,000 deaths per year due to radon induced lung cancer. The EPA states there is an “action” level which is equal to or greater than 4.0 Pico Curies per liter of Air (4.0 pCi/L). If a home or building has these levels, then mitigation is recommended to reduce the radon gas from entering.
Several agencies are in agreement that radon poses a serious health concern: World Health organization (WHO), US EPA, US Surgeon General, National Academy of Sciences and a host of others. Not only does the EPA recommend all homes be tested , but the US Surgeon General also put out a notice in 2005 stating that (paraphrased) indoor radon is the second leading cause of lung cancer in the US, breathing it over time can cause lung issues and it can be tested and simply fixed through well established venting techniques. Anyone that spends significant time in a home, school, hospital or any building can be exposed to radon. Pets are also at risk with continual exposure.
When Should Tests be Done?
The motivation to test homes for radon is often based on a real estate transaction however, any time is a good time to test for radon in your home. Remodels, room additions, changes to HVAC systems or to the foundation of a home are recommended times to test for radon. It is also recommended to test if your home hasn't been tested in the last 5 years.
Why use a Certified Radon Measurement Professional (RMP)?
A certified radon measurement professional has had specific training and passed a written exam on their knowledge of testing standards, analytics, reporting and requirements for radon testing in homes, schools, and other large buildings. Continuing education and recertification every two years is required. Certification is to maintain standards for the United States by either the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB) that certify per guidelines set by the US Environmental Protection Agency (EPA), the American National Standards Institute (ARST) and American Association of Radon Scientists and Technologists (AARST).
The devices used by a radon professional must also be calibrated periodically per the ANSI/ARST standards and maintain quality control records which ensure accuracy and consistency in a scientific manner. Certified radon testers assess the test conditions per known standards which help determine where and how to properly place, handle and retrieve radon devices.
A professional will help you determine which test is right for you, analyze your test results and give recommendations on the needs for follow up tests and or mitigation to fix your home.
Where is Radon in this country?
According to in depth studies by the EPA in the late 80s and early 90s, every state in the US has radon and all homes should be tested. Non residential buildings are also at risk and should be tested as well. The US EPA estimates that one in 15 homes in the US have elevated radon levels, and that every home be tested as it is the only way to tell if radon gas is present.
In Nevada alone, approximately 26% of the small subset of homes tested had a radon level at or above the EPA action level. The Reno / Lake Tahoe / Carson City region is among areas with the highest radon hazard potential, according to the UNR Extension Cooperative.
Radon can also be in water and is released into the air when water is used for showering or other household purposes. Radon in water is not usually a concern unless the source is ground water via a private well or public water supply system that uses ground water. Radon in water can also be tested and fixed. If you test for radon in air and have a radon problem, and have a private well, have your water tested. See our links page for more information on radon in water.
History of Radon
In 1984 an odd coincidence occurred, which came to be known as the Watras Incident. A construction engineer working on building a nuclear plant in Pennsylvania set off the alarm on the radiation detectors. Since there was no nuclear fuel in the plant yet, investigation discovered that he was bringing the high radiation levels from home, and the cause was radon gas.
The Watras home had 700 times the amount of radon considered to be safe. (Living there was equivalent to smoking a hundred packs of cigarettes per day!) He and his family moved out immediately, and the home was turned into a scientific laboratory for the long-term measurement of radon and the testing of radon mitigation approaches. After several months, the radon was reduced to an acceptable level, and the family returned. Today, the U.S. Surgeon General and the EPA recommend that all homes be tested for radon.
By 1988 radon was classified as a recognized lung carcinogen and by 1999 the largest study on underground miners and radon was released, which created a guideline for the EPA's current day action levels.
How Radon Enters a Home