Radon: Hazard or Hype? A Real Lung Cancer Risk

Radon: Hazard or Hype?

From my experience of over 20 years as a home inspector and PA DEP licensed radon testing professional, I know that radon is an often confused subject among most home buyers and sellers and even many real estate agents. I hear many agents tell their clients ‘not to worry about radon’ or that ‘radon is not real’. Well, it is indeed a real thing; its number 86 on the periodic table of elements and has been a known health risk since the 1800s.

Keep in mind, however, that radon testing is outside the scope of a home inspection. Many home inspectors, however, offer radon testing as an add-on service. Before hiring anyone to perform professional radon testing, please confirm that the individual is licensed by the PA DEP.

What is radon?

Radon is a radioactive gas that comes from the normal breakdown of uranium and radium (see graphic below) in the ground. It has no smell, no taste, and you can’t tell its concentration in your home without performing a simple radon test. As a normal part of nature, some substances within the Earth rise to the surface and radon gas is one of them. Some amount of radon is present in almost all homes, and, according to the US EPA, the south central PA region has the highest average indoor concentration of radon in the USA. This conclusion is based upon many years of actual test data collected from professional tests performed across the USA.

According to the US Environmental Protection Agency (EPA), radon is the second leading cause of lung cancer, after smoking. For non-smokers, radon is the leading cause of lung cancer. Approximately 22,000 Americans die from radon-related lung cancer annually. That is more than 6 times the number of deaths attributed to house fires and carbon monoxide (CO) poisoning combined! The use of tobacco substantially multiplies the risk of radon-related lung cancer (by a factor of approximately 15 times). Modern medical research has proven that, at least, 30% of people with lung cancer never smoked.

How does radon get into my home?

The EPA and PA DEP recommend that every home be tested for radon. The vast majority of radon emanates from the soil. It can enter the home in various ways; the most common is through cracks and voids in foundation walls and floors, and to a lesser degree via well water and building materials. We all know that warm air rises, so radon gas is also affected by indoor ventilation, such as the stack or ‘chimney’ effect. High radon levels have also been measured in schools and other buildings.

The stack effect relates to warm air rising within a structure and the need for replacement air to take its place from beneath. The stack effect can be driven by the method of heating that the home uses, direction and force of exterior winds, open vents and flues, and other combustion appliances. The space beneath a basement is most often the source of much of the replacement air. Since this space is in direct contact with the earth and radon most commonly emanates from the soil, this is the most common transport mechanism into a building.

Some real estate agents and home owners are erroneously under the belief that radon levels can’t be high in a city home or a new home or if the home is built on concrete slab (no basement) or over a crawl space or in homes with a daylight basement. I have personally measured high (and low) levels in all types and locations of area homes with and without basements. I have also heard all sorts of misinformation from real estate agents and from home buyers/sellers concerning radon. If you want to know the facts, about radon and clear up the many myths about radon, read on or give us a call.

While a home’s highest radon level is often found in a basement, this is not always the case. The same goes for the home’s age; I have found high concentrations in 200 year old homes and brand new homes and everything in-between. All homes should be tested.

Due to radon’s 3.8 day half-life, its daughter products (progeny) are actually more of a health hazard due to some of them having much shorter half-lives compared to radon. Nobody takes a breath lasting 3.8 days. Radioactive gases, such as radon, break down into other elements and isotopes as part of normal radioactive decay. The 5 things that radon breaks down into are Polonium 218, Lead 214, Bismuth 214, Polonium 214, and Lead 210. Polonium 214 is the biggest concern of these 5 items due to its 0.2 ms half-life. Each time these daughter products (all solids, mind you) break down, they release small amounts of energy. The very short half-life of Polonium 214 means that within an average human breath, Polonium 214 releases energy multiple times (each 0.2 ms) while the air is still in the lungs. This release of energy within the lungs damages lung cells and their DNA; as the damaged cells and DNA multiply, the damage also multiplies which can then lead to tumors (lung cancer).

What on earth is a “picoCurie”?

Radon concentrations are most commonly measured in picoCuries (pronounced “peek-o-ker-ees”) per Liter of air and abbreviated as pCi/L. A ‘Curie’ is a unit of radiation measurement named for Pierre and Marie Curie. A pCi is a trillionth of a Curie. Radiation is all around us; much of it naturally occurs from sources such as space and inside our bodies, but also comes from many other places, such as radon and medical sources (such as X-rays). There is much more radiation exposure from radon and X-rays than from nuclear power plants, cosmic rays, etc. Since breathing is the easiest way for a gas to enter the body, lung cancer is the primary result of radiation exposure related to radon.

Any level of radon (and radiation) may present a health risk. The US EPA has compiled a considerable amount of data relating to radiation exposure and results on the human body. The EPA has chosen 4.0 pCi/L as the Recommended Action Level. If a radon test result is 4.0 pCi/L or higher, remediation is recommended. Levels under 4.0 pCi/L may also be unsafe, but reduction methods in some cases may be more difficult under this level in certain homes. Even if a test shows a concentration less than 4.0 pCI/L, simple things like remodeling a home, weather-stripping doors or windows, reglazing windows, replacing HVAC equipment, or nearby blasting can change or create new entry points of radon into the home or affect internal drafting. In cases where one of the above occurs, performing another test is recommended.

What is used to measure radon?

Radon can be tested using several different technologies, including continuous radon (CR) monitors, e-Perms (Electret), activated charcoal (AC). These are the 3 most popular testing devices. Each has its own advantages and disadvantages although the continuous monitor is the most common technology used for professional testing during a home transaction.

Continuous Radon Monitor (photo courtesy of Sun Nuclear Corp.)

ePerm (photo courtesy of Rad Elec, Inc.)

Activated charcoal (AC) test kit

Closed House Conditions

Since radon concentrations can depend upon air movement, to properly and reliably test inside a structure, the EPA has set specific standards or protocols for testing called “Closed House Conditions” to help limit exterior effects and ensure reliable test results. The EPA defines “Closed House Conditions” as all exterior doors and all windows in the home (not just basement doors and windows) kept closed starting at least 12 hours prior to the start of the test. This does NOT mean to close the windows and doors once the inspector arrives to start the test. Exterior doors can be opened and closed momentarily for normal entering and exiting the home, but must otherwise remain closed during the test. Central heating or A/C systems must be run normally beginning 24 hours prior to the test’s start and then throughout the test’s duration. This helps ensure real life occupancy conditions in the home. Whole-house fans and window or wall mounted A/C units (unless running in circulating mode) must not be operated during the test since they exchange air with the exterior. Chimney flue dampers should also be closed and fireplaces should not used during the test unless they are the home’s only heating source.

PA DEP has documented set standards and protocols for professional radon testing professionals to follow; some of these PA DEP protocols are more stringent than what the US EPA requires. For example, PA DEP requires that radon testing occur in the lowest possible living level. This normally is the basement unless there is a dirt floor or the ceiling height (between the basement floor and underside of the main level’s floor joists) does not allow for normal living conditions. EPA regulations, on the other hand, would call for radon testing on the lowest level suitable for occupancy. If the basement can’t easily be used for occupancy, radon testing (in areas following EPA rules), would most often be performed in the area above the basement. In PA, however, we would test in the basement as long as the basement doesn’t have a dirt floor and an average adult could stand up in that area.

When the inspector arrives to drop off and retrieve the test, he will do his best to verify that closed house conditions have been met. The inspector will communicate with the seller or home’s occupant a day or so prior the test’s start to review PA DEP (Dept. of Environmental Protection) radon test protocols and answer any questions. This communication is made before the test starts because the test protocols begin well before the test starts and the home should be ready for the test to be performed before the radon testing professional arrives.

Most, if not all, certified radon testers have the home’s seller or occupant sign a test ‘non-interference’ agreement which explains the test criteria and also is a form of quality control. This form helps ensure that the owner or occupant understands and will fully comply with the required test protocols and affirms that they won’t interfere with the test. Should any evidence of inference be noted based upon that the inspector finds or what the test results indicate, the test must be voided per PA DEP protocols since the results can not be relied upon for accuracy.

The EPA and PA DEP also have specific requirements regarding where in the home radon testing can occur. Radon testing should not occur in areas of high humidity such as kitchens, laundry rooms, and bathrooms. Radon testing equipment must be located at least 12″ away from exterior walls, at least 36″ away from windows and doors, and, at least, 20″ above floor level (normally between 20″ and 60″ above the floor). Radon tests should not be located in enclosed areas such as closets. I have personally inspected homes over the years and that found another radon testing professional placed a radon test in a bedroom closet which, of course, is not a valid placement location. Radon tests should be placed away from heat sources, away from drafts (such as not near HVAC supply registers, ceiling fans, or dehumidifiers or humidifiers), and not in direct sunlight.

Click here to learn more about PA DEP Radon Testing Protocols. These protocols ensure quality control and sets standards for PA DEP radon testing professionals. For all radon tests that we perform, we are required to follow these protocols and we provide this list to the home seller before the radon test begins so that they are prepared before we arrive to begin the radon test.

What if a radon test indicates a high radon level?

If a radon test shows a high levels, remediation (also called mitigation) can be successful in lowering the home’s radon level in most circumstances. The most common method of remediation is a sub-slab depressurization system. To put it simple, one (or more) hole is drilled through the foundation slab (often the basement’s concrete floor), a small amount of dirt is excavated under the slab, PVC pipe is installed with a special fan, and this system vents to the exterior away from doors and windows. Radon fans can only be placed in an attic or at the exterior of the home, but can not be installed in the home’s living space or in the garage.

Since inspecting homes since 2002, I’ve seen many improper radon system installations. The Commonwealth of PA has specific requirements (called the “PA Radon Mitigation Standards”) about how and where remediation systems can be installed. Professional remediation systems in PA must be installed to these standards. The cost of a professionally installed remediation system in our area is generally in the $800~$1,500 range. Remediation system designs (and their pricing) can vary based upon the home’s layout, the initial test result, type of system installed, number of suction points needed, etc. PA DEP also requires that when a professional remediation system is installed and is started up, a retest must occur between 24 hours and 30 days.

The professional remediator who installed the system may not perform the retest; this is to prevent a possible conflict of interest. The remediator will either provide a test kit to the home owner (or new home buyer) to perform the test themselves (and then mail the test device to a certified lab for the results) or will pay a separate PA DEP certified tester to perform a professional retest.

It is very important that the retest be performed promptly after the remediation system is running so that lower radon levels inside the home with the system running can be confirmed. I have personally tested high levels in quite a few homes with running remediation systems; when a home owner or potential buyer sees the installed remediation system or the installed manometer, they most often assume that the system is working as intended and the radon levels inside the home are low. Again, the only way to know is to test.

Who performs a radon test and remediation?

Homeowners can test their own home for radon or to help ensure a more accurate test performed to PA DEP/US EPA protocols, they can hire a PA DEP licensed radon testing professional. The PA DEP requires that all individuals or firms performing professional radon testing or remediation be licensed by the Commonwealth of PA. A home owner or builder can perform radon testing and remediation in their own homes, however a PA DEP licensed testing professional should be used for a home transaction to ensure a non-compromised test performed to PA DEP protocols. Any changes to an installed remediation system should only be performed by a licensed remediator, as well. Contractors (plumbers, electricians, etc.) who are not PA DEP licensed for radon remediation should never modify remediation piping or their fans in any way; this is against the law in PA per the PA Radon Act. Even minor changes to remediation pipes and fans may cause the system to not work properly, may lead to condensate damage within the home, and/or may raise the radon concentration within the home.

The PA DEP updates its list of PA certified/licensed radon testers and radon remediators each month. This info can be obtained from the PA DEP website or by calling the PA DEP at: 1-800-23-RADON

Matthew Steger is a Certified Level 1 Infrared Thermographer, an ASHI Certified Inspector (ACI), and an electrical engineer. He can be reached at matthew@thehomeinspectorsnotebook.com. No article, or portion thereof, may be reproduced or copied without prior written consent of Matthew Steger.