I Live In Texas - Can Radon Be A Danger Here?
Yes it can, even in the Dallas - Ft. Worth - North Texas Area.
Alpha Energy Laboratories (who specializes in Radon testing nationwide) sent out several thousand kits at cost to see what percentage of homes had elevated radon levels. A full 10 % came back with levels above 4 pCi/L (picocuries per liter) and there was even one which measured over 100 pCi/L. So radon is not a problem just in the North or in homes with basements. It can be a problem anywhere and it varies home to home. Finding out for yourself is relatively inexpensive way to prevent possible health issues down the road.
Q. How Long Does A Radon Test Take?
A. Many people who need a Radon test are prospective home buyers and there is
often a narrow window of time to close on the property during which inspectors
can be called out. Short term radon kits normally require 48 hours to develop (for the test to be compliant with EPA protocol),
and Alpha Energy can rush reports within 24 hours. (with an extra fee being
charged) Otherwise, it takes three days. So the minimum time required is three
days with a rush fee, and five days without, plus the lab is closed on weekends and after 5 PM.
ScanTech now offers a Radon Pre-Screening test which can indicate the same
day whether a short term kit should be employed. We utilize a high sensitivity
digital Geiger counter to measure background radiation levels and an Air Ion Counter to pick up traces of radioactive decay. This test is not legally binding or compliant with EPA protocol, but if you are sitting on the fence as to whether it is worth the trouble to do a full test, then this could help make up your mind.
There are professional grade radon detectors that can give a fairly conclusive sampling that will be within +/- 10 % of actual (as compared to +/- 25 % for the charcoal kits) but these typically run over $5000 and are still not in EPA protocol unless left for 48 hours or more. Some home inspectors use these and let them run for 2 hours with 8 tests of 15 minutes each. (discarding the first test and averaging the remaining 7)
Here are some good facts on Radon risk taken from the EPA's website.
Here is a link to the EPA website from which the information on this page
was derived.
Q. What Is the Average Level of Radon in the Home?
A. Based on a national residential radon survey completed in 1991, the average
indoor radon level is 1.3 pCi/L in the United States. The average outdoor
level is about 0.4 pCi/L.
Q. Is there any level which is completely safe?
A. Only 0, which is generally not practical as even the outdoor level is measurable. The risk of radon exposure is completely linear - as levels increase, so does the risk of health effects. There really is no safety threshold per se. (except 0)
Then why 4.0 pCi/L? This was set as as standard with respect to ALARA. (as low as reasonably achievable) If the standards were lower (like 2.0) then the potential cost and difficulty of mitigating certain homes and structures could become untenable. Also, below 4.0, the risk presented by radon gas becomes secondary to other potential factors and safety issues in the home. (realistic assesment of the overall picture)
Q. Is radon really dangerous?
A. On the Internet, a rumour is going around that radon is not really as serious as studies would suggest and that the combined health effects with smoking are greatly overstated. According to some experts, danger from radon goes in and out of fashion with time, but the effects are the same regardless of public perception.
The problem with health factors such as radon gas is that the onset of symptoms or effects can take a relatively long time - 10 to 20 years or more and in the meantime there is no sign that anything is amiss. It is odorless, tasteless and has no real symptoms that can be attributed. (such as headaches or dizziness from carbon monoxide poisoning) But an estimated 20,000 people die every year from radon gas in the United States, the equivalent of a jumbo jet plane crashing every week. But these deaths are not spectacular or as directly linked as a airliner wrecking, so the perception tends to be "So what?"
Q. Won't discovering Radon ruin my property values or peace of mind?
A. Testing for radon is inexpensive and not very complicated. Fixing a problem typically costs less than many other home projects and repairs - sometimes just adding a vent fan is all that is necessary.
Q. Can you test the Radon level in soil before hand?
A. Yes, and normally you need special radon kits that are designed for this purpose and they need to be placed inside of a hooded enclosure. Unfortunately, studies have shown that there is little correlation between radon readings obtained in this fashion and the actual readings in a home built on the site. This is due to multiple variables in how the structure is built, construction materials and home design.
Q. Can there be Radon present in water?
A. Yes, radon gas may enter the home through contaminated well water and it may be released into the air when bathing or doing dishes. This is primarily a concern if you get your water from underground sources such as a natural spring. Drinking the water directly however, is thought to be less risky than radon found in the air.
Q. Are there seasonal fluctuations?
In general, yes. The wintertime will tend to show higher levels due to the home being more closed up. In summertime you may not even observe an issue due to the self mitigating circulation of air from A/C or open windows. If the property tests within guidelines during the summer, it would be wise to measure again in the winter.
Also, there are diurnal fluctuations where radon tends to increase at night due to loss of wind and the "stack effect". This occurs more when outside cooler air combined with rising warm air from interior heating start to pull more radon gas from the earth.
Radon
Radon is a gaseous radioactive element having the symbol Rn, the atomic number 86, an atomic weight of 222, a melting point of -71ºC, a boiling point of -62ºC, and (depending on the source, there are between 20 and 25 isotopes of radon - 20 cited in the chemical summary, 25 listed in the table of isotopes); it is an extremely toxic, colorless gas; it can be condensed to a transparent liquid and to an opaque, glowing solid; it is derived from the radioactive decay of radium and is used in cancer treatment, as a tracer in leak detection, and in radiography. (From the word radium, the substance from which it is derived.) Sources: Condensed Chemical Dictionary, and Handbook of Chemistry and Physics, 69th ed., CRC Press, Boca Raton, FL, 1988.
