New radon exposure risk

New Radon Exposure Risk: Impact on Health and Indoor Air Quality

Radon: Why worry about it?

Many of us think of radon as something in the basement. We commonly test for radon when buying a home. We may install a radon mitigation system. But there are new health exposures relating to natural gas usage that may increase radon levels in your home even if it previously tested low.

Some Background

What exactly is radon and how does it affect us?

Radon is a cancer-causing, naturally-occurring, radioactive, odorless, colorless gas that forms as the uranium or thorium in the earth decay. Granite and shale contain the highest concentrations of uranium. One of the highest average radon concentrations in the United States is found in the Marcellus Shale region in southeastern Pennsylvania. Westchester and Fairfield counties are loaded with granite so radon testing is common when homes change ownership.

Radon and Lung Cancer

According to the EPA, radon is responsible for much of the public’s exposure to ionizing radiation and is believed to be the second leading cause of lung cancer in the US. Due to lung shape and size differences, children are even more vulnerable than adults. The risk for children may be almost twice as high as the risk to adults from the same amount of radon– and if the child also is exposed to tobacco smoke the risk of getting lung cancer increases at least 20 times.

Radon in Our Homes

Historically, the main source of radon in a home was migration of the gas through cracks and openings the foundation. Given its “heavy” nature, when it enters it tends to concentrate in basements and crawl spaces, which is why these areas are where radon tests usually are performed.

As radon breaks down, it turns into radioactive particles that adhere to surfaces and dust particles. If not blown or filtered out of the air, inhaled radioactive particles can stick to the passages of the lungs and potentially cause cancer.

There also is radon in water, particularly ground water from wells or public water from ground water sources (surface water is less of an issue). If your water tests high for radon, it’s best treated at the point it enters your home.

New Health Risks from Radon

Natural gas also contains radon and it is released when gas is burning. All gas appliances—such as boilers, hot water heaters, fireplaces, dryers, and cooktops—may elevate radon levels in your home, including in the living spaces, if not properly vented. At a minimum, we recommend that clients avoid gas appliances with constantly burning pilot lights. It’s very important to add ventilation (when cooking, for instance) to try to reduce the risk of radon in your home’s indoor air.

A new risk: residents of metropolitan New York and Connecticut may now be exposed to much higher levels of radon from natural gas than previously. Although the natural gas supply in our area historically has come from the Gulf of Mexico, which has a low level of naturally occurring radon, since November 1, 2013 some of the natural gas being supplied to our area is from the Marcellus Shale in Pennsylvania. This area has one of the highest concentrations of radon in the country. If hydrofracking (“fracking”) and pipelines are expanded, even more of our area’s natural gas may come from this high-radon shale in the future.

What You Can Do

  • Build tightly sealed homes and foundations to prevent radon from migrating into the home from the ground and add whole house ventilation (as the DOE says: “Build Tight, Ventilate Right”)
  • When choosing gas-fired appliances and equipment, select high efficiency, well-ventilated models with no pilot light
  • Install a radon mitigation system and a whole house heat recovery ventilation system (HRV or ERV) as part of all new construction projects, including basement ventilation
  • Hire a licensed radon tester and system installer to investigate and remediate any radon issues that they identify. It’s a good idea to test at the end of construction projects as well as on an ongoing basis. Review radon information at [] for links to more radon information and state licensed radon mitigation companies
  • Re-test for radon every two years, whether or not you have a mitigation system, and have your mitigation system serviced every five years
  • In existing homes as part of an energy efficiency retrofit, have the cracks and openings in the foundation and crawl spaces sealed to reduce migration of radon from the soil around your home
  • Consider installing an HRV system to increase ventilation throughout your home and bring in a constant supply of fresh air. It’s a great way to improve indoor air quality and rid your home of air-borne toxins
  • Take steps throughout your home to increase your home’s energy efficiency to reduce your demand for natural gas
  • Support legislation to require testing for radon levels in natural gas arriving from the Marcellus Shale as well as to ban hydro-fracking (“fracking”) in the Marcellus Shale region and the Algonquin Pipeline (

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