Now there's a quick, inexpensive way to find out if a deadly visitor is seeking refuge in your home. Is radon calling?
PHOTO: FOTOLIA/CONCEPT W
Now there's a quick, inexpensive way to find out if a deadly visitor is seeking refuge in your home. Is radon gas calling?
By now, the presence of radon gas in many U.S. homes has been widely reported. Radon, a decay product of uranium, rises from the soil and is often trapped inside buildings. Once there, the colorless, odorless gas and its radioactive decay products (often called daughters) attach to dust and can be inhaled by occupants. Centers for Disease Control scientists now estimate that indoor radon is the number two cause (after cigarette smoking) of lung cancer in the U.S. and is responsible for between 5,000 and 30,000 deaths per year. Unquestionably, radon is an extremely hazardous form of indoor air pollution.
Test to Find if Radon Gas is Present in Your Home
Most of the publicity about radon has concerned one so-called hot spot in the eastern part of Pennsylvania, an area which is underlain by significant uranium deposits. But recent evidence has begun to show that high indoor radon levels are far more pervasive than first imagined. Information compiled from over 50,000 samples taken by Terradex Corporation's testing laboratory shows that only five out of 50 states have so far failed to show at least one case of a radon level above the Environmental Protection Agency's recommendation for homes built on sites contaminated with uranium-processing waste. And there have been fewer than a dozen tests done in each of those states, so more bad news may well be yet to come.
What's more, data from a study done by the Bonneville Power Administration have shown that it's not just tight, energy-efficient houses that are susceptible, as was previously supposed. Field monitoring of super-insulated homes with air-to-air heat exchangers and conventional leaky houses showed little difference in radon levels. It's now estimated that as much as 10% of the homes in the U.S. have indoor radon levels that exceed the EPA's recommendation.
Testing for Radon Gas
How do you find out if your home, or a house you're planning to buy, has dangerous radon concentrations? Terradex Corporation (Walnut Creek, CA) will send you its Trak Etch monitors, which remain in your home for 30 to 90 days and are then returned to the lab for analysis. It usually takes about 90 days for a complete test, and the service costs about $80. Terradex's system involves what is essentially photosensitive material that is etched by radioactive decay particles. It has been widely used by individuals and government agencies. In fact, Terradex tested the earth-sheltered house at the MOTHER EARTH NEWS Eco-Village, which we're pleased to say turned up clean.
Another testing service, Airchek (Penrose, NC), uses a method that was refined for indoor measurement of radon gas by Dr. Andreas C. George of the U.S. Department of Energy's Environmental Measurements Laboratory. Airchek sends a porous bag containing 50 grams of activated carbon (charcoal) that is exposed in the home for four to six days, absorbs radon, and then is sent to a laboratory for analysis. Typical total turn-around time for the standard service is three to five weeks, and the cost is $19.95.
From both a time and a cost standpoint, Airchek's testing has obvious advantages. You can order either the standard ($19.95) or the deluxe ($29.95) service from Airchek by major credit card over a toll-free line. Within 24 hours, the staff will ship a package to you by first-class or bulk-rate mail (standard service) or United Parcel Service blue label (deluxe service). Inside the airtight, foil-lined envelope, you'll find a brown bag with the activated carbon, instructions, and a return envelope.
The sample bag stays in your home — located according to Airchek's detailed instructions — for four to six days. Then you seal it carefully in the airtight, foil-lined return envelope and send it to the laboratory by first-class mail, UPS, or whatever method you prefer. (Bear in mind that you pay the postage on this leg.) It's important, however, to get the sample to the lab as soon as possible after it's sealed. After about six days, the radon decays to the point where it begins to affect the accuracy of the test; after ten days, about 50% loss can be expected.
All laboratory work is done by Alpha Energy Laboratories in Dallas, Texas, using sophisticated, computer-controlled sodiumiodide testers. Alpha Energy has been doing this sort of work for five years, and the laboratory manager has 18 years of experience in radiation measurement. Testing is completed within 24 hours of receipt of the sample, and the results are transmitted over phone lines from Alpha Energy's computer in Dallas back to Airchek's computer in North Carolina. Before another 24 hours have elapsed, Airchek will send you the results by first-class mail. Those ordering deluxe service will also receive a phone call within 24 hours of the completion of testing, as well as preference at all stages of processing. Deluxe service customers can expect results within 10 to 12 days of ordering the testing.
Airchek's technician also has a method to recommend for people who are interested in testing property before buying or building on it. Erect a roughly 4 foot by 4 foot temporary tent out of 6-mil plastic, propping the center up with a two-foot pole and weighting the edges down with rocks or boards. Hang Airchek's sample bag on a nail halfway up the pole, and cut a small, scalloped ventilation hole near the top but on the other side of the pole from the bag. (Don't allow rain to fall on the sample bag.) Radon will rise from the soil and pass by the activated carbon on its way to the small vent.
Because government agencies have yet to settle on what level of radon constitutes a significant hazard, Airchek has divided the scale into three areas. A measurement of less than 4 picoCuries (pCi) per liter is safe, 4 to 8 pCi/1 is warm, and greater than 8 pCi/1 is hot. If your test shows less than 4 pCi/1, you have little to worry about. In the 4- to 8-pCi/1 range, you might consider retesting to confirm the reading and then instituting some simple control strategies. If your house has more than 8 pCi/1 of radon and its decay products, you have cause for concern. For customers who order before April 1, Airchek will rerun the test for free to confirm an 8 pCi/1 or higher reading. Airchek will also tell you how to get help in improving your indoor air quality. Unless you request otherwise, all testing results will be kept confidential.
Airchek's speed and price put radon gas testing within almost anyone's reach. And it's really a small price to pay to beat lung cancer to the punch.