Reliable Radon, LLC
Shopping Cart
Your Cart is Empty
Quantity:
Subtotal
Taxes
Shipping
Total
There was an error with PayPalClick here to try again

Radon Mitigators Erik Fardy
My Blog
Blog
NH DES Recommendations 2015
Posted on November 5, 2015 at 11:21 AM |
![]() |
Radon in Your Home: An Overview for New Hampshire Homeowners RADON OCCURRENCE IN A HOME
2015 Radon is a naturally occurring radioactive gas that is commonly found in bedrock and in water from
bedrock (drilled) wells in New Hampshire. Radon gas is colorless, odorless, and tasteless.
Radon gas finds its way into indoor air mainly by migrating from bedrock, through the soil, and into the
home via cracks or other openings in the foundation. Radon from bedrock wells is released into indoor
air during showering, dishwashing and doing laundry. Dug wells and point wells tend to have minimal to
no radon. The amount of radon released from stone building materials such as a granite block founda-
tions, fireplace materials, counter tops and floor or wall tiles is usually insignificant. HEALTH RISK and MEASUREMENT Exposure to radon poses an increased risk of developing certain types of cancer, primarily lung cancer
and stomach cancer. Radon concentrations in both air and water are measured in picocuries per liter
(pCi/L). A general rule of thumb is that for every 10,000 pCi/L of radon in a home’s water supply, the
radon concentration in indoor air is increased by 1 pCi/L. RADON RISK FROM AIR The increased risk of lung cancer is due to inhalation of radon-laden indoor air, including any radon en-
tering the building through the water supply. (There is also an increased risk of stomach cancer due to
ingesting radon in drinking water.) Any amount of radon in air or water increases one’s risk of lung can-
cer; the greater the amount, the larger the risk. Radon is the leading environmental cause of cancer
deaths in the U.S. and the leading cause of lung cancer in non-smokers. Exposure to the combination of
radon gas and cigarette smoke creates a greater risk for lung cancer than either factor alone. Long-term
exposure to radon leads to the deaths of an estimated 100 New Hampshire residents each year. RADON RISK FROM YOUR HOME’S WATER SUPPLY The main health risk associated with radon in water is from breathing radon released into indoor air.
According to the National Academy of Sciences, 89 percent of the risk from radon in a home’s water
supply is the increased lung cancer risk from inhalation of radon that the water adds to the air in the
home, while the other 11 percent is due to other cancers, primarily stomach cancer, due to drinking the
water. This risk estimate is based on the typical situation in which every 10,000 pCi/L of radon in water adds 1 pCi/L of radon to the air. For example, if a home using a bedrock well has 5,000 pCi/L of radon
in water and detects 4 pCi/L of radon in the indoor air, then one would make the following calculations
to estimate how much of the radon in the air is due to the presence of radon in the water supply, how
much is due to natural background conditions, and how much is due to infiltration: Example:
0.5 pCi/L from water (5,000 divided by 10,000) 0.4 pCi/L from “background” (outdoor air; see REDUCING HEALTH RISK below) 3.1 pCi/L from infiltration of high-radon air through the foundation (4.0 - 0.5 - 0.4 = 3.1) 4.0 pCi/L total radon in air
Every home is different in terms of the relative contributions of air and water to the total radon risk,
which is why NHDES recommends testing air and/or water according to the flow chart on page 4 and
consulting with a certified radon mitigation provider and (if radon in water is a concern) with a radon-in-
water treatment professional. However, in the example above and in most cases in New Hampshire in
which total radon in the indoor air is elevated, infiltration of high-radon air through the foundation con-
tributes more to the overall health risk than radon in the water supply, and addressing infiltration is usu-
ally more cost-effective than treating the water.
Nevertheless, it is quite common for water from bedrock wells in New Hampshire to have radon levels
that pose a significant health risk (based on a lifetime of exposure) in comparison with other common
drinking water contaminants. NHDES’ Environmental Health Program considers the risk of one excess
cancer case per one million people exposed over a projected 70-year lifetime to constitute a significant
health risk. The U.S. Environmental Protection Agency (EPA) considers significant health risk to be in
the range of one per million to 100 per million people exposed. At 2,000 pCi/L of radon in the water
supply, the estimated contribution to radon in air is 0.2 pCi/L, and the associated estimated total (lung,
stomach, etc.) increase in cancer deaths is 1,300 per million people exposed.
There is no federal or state standard for radon in drinking water. NHDES recommends that at 2,000
pCi/L or greater in water, homeowners should test the indoor air for radon and consult with radon miti-
gation and water treatment providers on the advisability of taking measures to reduce their exposure to
radon in air. In most cases, “mitigation” of radon in air by preventing infiltration of air through the
foundation is more effective and less expensive than treatment to remove radon from water. In cases
where radon in water is contributing significantly to radon in air, radon-in-water treatment may also be
warranted. Accordingly, NHDES recommends testing both air (if living space in the home is below the
third floor) and water (if from a bedrock well). These results, reviewed with a certified radon mitigation
provider, will help homeowners to make well-informed decisions about the best way to reduce their ex-
posure. REDUCING HEALTH RISK
The U.S. Surgeon General and EPA recommend testing for radon in air in all living spaces below the
third floor. The U.S. Congress has set a long-term goal that indoor air radon levels be no more than out-
door levels, which average around 0.4 pCi/L. While this goal is not yet technologically achievable in all
cases, radon in most homes today can be reduced to 2 pCi/L or below and EPA strongly recommends
treatment when the radon indoor air concentration exceeds 4 pCi/L. Approximately 27,000 cancer deaths
can be expected for every 1 million persons exposed for a “lifetime” (70 years) at 4 pCi/L. Radon miti-
gation is achieved mainly through reducing the passage of radon through foundations and, in some cas-
es, treating bedrock well water to remove radon. TESTING FOR RADON
NHDES’ recommendations for testing and reducing exposure to radon are summarized in the flow chart
on page 4 of this fact sheet.
Testing for Radon in Air – Both short-term and long-term testing methods are available. For infor-
mation on testing radon in air, please visit http://www.epa.gov/radon/radontest.html, call (800) 767-
7236, or search the internet for “USEPA Where Can I Get a Radon Test Kit?” NHDES recommends us-
ing nationally certified radon-in-air measurement providers. Certified radon service providers can be
found at www.nrsb.org and www.nrpp.info. Testing Water for Radon – For an up-to-date list of New Hampshire-accredited laboratories that con-
duct analyses for radon in water, visit the NHDES website des.nh.gov, click on “A to Z LIST” in the up-
per right or left corners, and select “L” and then “Laboratory Search.” On the “Accredited Laboratory
Search” page, select “DRINKING WATER” for the Matrix, and for “Analyte” select “RADON,” and
then click on “Submit Query.” Radon concentrations in well water can vary substantially from one test to
another. NHDES recommends at least two radon tests (at least one month apart when possible), prior to mak-
ing any treatment decisions. Because radon is not the only potentially harmful radioactive substance com-
monly found in New Hampshire well water, NHDES also recommends testing water from private bedrock
wells for uranium and analytical gross alpha; some laboratories offer these tests as a package along with radon. A well that has high levels of radon is more likely to have high levels of uranium and/or gross alpha.
Radon Measurement and Mitigation Service Providers and Equipment Suppliers
Since January 1, 2015, all radon-in-air mitigation designers and installers must be nationally certified to
perform those services in New Hampshire. Certification is not required for radon-in-air testing or for
radon-in-water treatment, but some radon-in-air testing providers are nationally certified. Certified radon
service providers can be found at www.nrsb.org and www.nrpp.info. Suppliers of radon water treatment
devices can be found on the internet and in the Yellow Pages under listings for “Water Treatment,” “Wa-
ter Conditioning,” or “Radon Testing & Services.”
ADDITIONAL RESOURCES
• A Citizen’s Guide To Radon, The Guide to Protecting Yourself and Your Family From Radon
(USEPA, 2012), available at http://www.epa.gov/radon/pubs/citguide.html
• Information and publications about all aspects of radon at http://www.epa.gov/radon • NHDES Fact Sheet ARD-EHP-22, “Radium, Radon, and Uranium: Health Information Summary,” available at http://des.nh.gov/organization/commissioner/pip/factsheets/ard/documents/ard-ehp-22.pdf
• NHDES Fact Sheet GEO-2, “Radon in New Hampshire,” available at
http://des.nh.gov/organization/commissioner/pip/factsheets/geo/documents/geo-2.pdf
• Risk Assessment of Radon in Drinking Water (National Academy of Sciences, 1999), available at http://www.nap.edu/download.php?record_id=6287#
Note: During real estate sale or financing transactions, or at other times, parties may choose to test indoor air and
water supply concurrently to save time.
|
Categories
/