Frequently Asked Questions
Questions
About Radon
Questions
About Radon Mitigation
Questions About Radon Testing:
Where does radon come from?
Radon is a naturally occurring gas that results from the
breakdown of uranium commonly found in soil.
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How does radon enter my home?
Radon comes up through the soil and rocks surrounding your home
and seeps through cracks in concrete walls and floors, floor drains,
sump pumps, joints, and hollow-brick walls.
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Why haven't I heard of the radon danger
until recently?
Radon has always existed. However, it was not until the 1980s
that dangerous radon levels were found inside homes across the U.S.
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What are the health risks?
Radon is the second leading cause of lung cancer.
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How do I know if I have radon in my home?
By testing with an EPA-listed or State-certified easy-to-use,
inexpensive test kit as soon as possible, or by hiring an EPA-listed
or State-certified contractor to test your home for you.
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If I have a radon problem, can it be
corrected?
Yes. The use of trained personnel is recommended. State radon
offices can recommend qualified contractors. In some cases, the
problem can be treated by the homeowners if they have experience
with other kinds of home repair.
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Will my neighbor's radon measurement
indicate whether or not I have a radon problem?
No. Radon levels vary from house to house. The only way to know
if you have a radon problem is to conduct a test.
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How can I get a reliable radon test kit?
Kits can be purchased through the mail or from your local
grocery or hardware store or other retail outlets. Look for a test
kit from a company that is State-certified or "qualified" (see
www.epa.gov/radon/radontest.html for information on how
to find a "qualified" radon service professional in your
area).
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Questions About Radon Mitigation
Why does the radon fan
have to be outside my home?
We would much prefer to put the fan in the basement, where it will
live longer and be less obtrusive. However, the EPA makes us put the
fan outside the home, out of fear that the fan or rubber couplings
might leak, causing radon-laden soil gas to be pumped into the house
"perhaps for years" as they put it. [Presumably this would occur
without the homeowner seeing, hearing or smelling anything out of
the ordinary, without ever checking on the system's radon
performance, and/or without caring.]
This paternalistic requirement is a relic from the early days of
the radon industry, when makeshift or poorly designed fans were the
norm. The industry has moved on with leak proof fans, continuous
radon monitor/alarms and much-improved installation techniques, but
despite a longstanding promise to revisit the issue, the EPA is
stuck in the past. Worse yet, some states have adopted the EPA's
antiquated guidelines as regulations, and with all those
bureaucracies having their hands in the pot, it appears unlikely
that reason will ever prevail.
It is interesting that the EPA admits that they have never found
a case where the leakage was significant enough to make the radon
system totally ineffective (as would happen from a complete fan
failure). Guess that doesn't matter. [EPA Technical Guidance Manual
- 625/R-93-011, page 152]
We do offer two optional EPA-approved configurations that feature
more attractive fan locations. Our Reverse-Flow Systems have the fan
in the basement, and our Hidden Fan option puts it in the attic or
garage. These may entail significant extra costs, and are not
feasible on all homes.
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Why does the exhaust
pipe go way up to the roof?
EPA rules again, but this time with somewhat more justification. The
idea is to keep the exhaust gas from coming back into the house or
impinging on patios, walkways, play areas, etc. There are three
basic requirements: The exhaust must be
(a) at least ten feet off the ground,
(b) above the eave [not necessarily the edge] of the roof, and
(c) either ten feet away from, or two feet above, windows.
It's not necessarily a good idea to pump the exhaust gas up high.
Apart from the unsightly appearance, the added piping and elbows
create backpressure that reduces the effectiveness of the radon
system. Also, it's not really clear that this configuration produces
less reentry of gas than (say) a ground level exhaust on a blank
wall. Finally, in cold weather condensation forms and freezes on the
interior of the pipe as the soil gas is cooled during its journey
(Just like when warm summer air cools on contact with an iced tea
glass), causing complete failure of the radon system. As with
Question 1, there is little chance of a change, though.
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Why doesn't the system
have a cap or screen? Won't rain and bugs get in?
A cap or screen creates a wonderful place for ice to form as the
warm, moist exhaust impinges on it. Bugs are not a problem, because
there's air blowing outward, typically at 20-40 cubic feet per
minute. Besides, where are they going to go? Into the ground under
your house? Bugs are not particularly bright, but they don't need to
fight through a radon fan just to get into the dirt.
Regarding rain entry, the fan is designed to take it. But even
more importantly, a three inch rainfall would produce only about a
cupful of water if it all flowed down to the bottom. The system
actually removes much more moisture than it could possibly let in!
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Why do you have to use
that ugly PVC? Why not tubing to match my downspouts?
We would dearly love to use aluminum downspout material, but there
are problems. First is the cold weather operation as discussed at
the end of FAQ 2. Metal downspouts have great heat transfer, and
would be filled with ice for most of the winter, disabling the
system just when you need it the most. There could even be physical
damage from up to 100 pounds of ice plug. Secondly, the downspout
would be unacceptably noisy, both from rattles and from the airflow
itself. Finally, it is utterly impractical for us to stock up on all
the available (and discontinued) colors of downspouts.
Our compromise to all this is that the pvc can be painted, and
will then effectively disappear.
Incidentally, unlike many radon contractors, we have standardized
on 3 inch piping instead of the traditional 4 inch. Because the
airflow is faster in a small pipe, we have to be especially careful
of noise control, and must invest a little more money in the fan.
But the result is a dramatically improved appearance.
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If you cover my sump,
how can I tell if the pump is working? How can I fix it if it fails?
We have tried a lot of different materials for sump covers, and have
standardized on transparent 1/4 inch Lexan, something that lets you
shine a flashlight into the sump for easy inspection.
By the way, this is NOT "cheap plexiglas" as one of our
spectacularly uninformed competitors charges. Not even close. In
fact, fighter aircraft canopies are made of Lexan, a material that's
crystal clear, tough and durable as all get-out. Unlike the cheap
black plastic that is generally used in the radon business, Lexan
will never become brittle or break into sharp shards. Doesn't turn
brown over time, either. It costs more than the alternatives, but we
think it's well worth it.
Finally, our system is designed for easy maintenance. We include
a rubber quick-disconnect on the piping (removable with only a
screwdriver), and the sump cover is caulked into place (no fasteners
to rust). The cover is rectangular, not round ... self-aligning so
that when you reinstall it, the whole thing pops back into place. If
you have been careful, it may not even need any caulk touchup.
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Why do you need to fuss
with my sump at all?
The idea is to put a vacuum on the drain tile that surrounds the
foundation. The builder put it there to collect water, but we can
use it to collect gas too. Because the drain tile is connected to
the sump, we have to seal it to hold the vacuum. As gases come
percolating through the soil, they are drawn off into the drain tile
and then into our radon piping. Instead of passing through the
house, they are confined to a three inch tube. Elegant.
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Why do you need to
replace my sump pump?
As discussed in FAQ 6, the sump is a means to an end. Your pump's
float valve must be set low enough to keep the drain tile dry. If
the drain tile is allowed to fill with water, it will no longer
function as a vacuum collector.
Also, if you have a pedestal style sump pump (the kind where the
motor sits above the basement floor) it generally needs to be
replaced so that the airtight seal can be maintained.
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My home has a very high
radon level. Can it be fixed?
How much good news can you stand? In our experience, the homes with
the very high initial readings have been the easiest to fix, and
have had the lowest post-mitigation radon levels. Here's the
reasoning. Very high radon levels mean very loose soil conditions,
and in these situations our system's vacuum will cover the entire
footprint of the house, reducing radon levels to near outdoor
levels. One recent Ann Arbor home began at 216 pCi/l and ended at
0.6.
The tough homes are usually those with slightly elevated radon
levels, frequently built on clay. There all the radon might be
coming in from one fissure, and the tight clay might prevent our
system vacuum from reaching it. We could take several tries and
several suction points before finding the right location. We are
very stubborn, and always win.
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Joe Blow promises to get
the radon level below 2, and you only promise 4. Why should I go
with you?
Promises are only as good as the company making them. More
than 95% of our installations systems wind up below 2, and all of
them are below 4. We simply will not promise something that we
cannot deliver on 100% of the time.
In some situations it simply may not be possible to get the radon
levels much below 4 pCi/l. After all, that's why EPA chose 4 as the
Action Level. They were required by law* to choose the lowest level
that could be achieved on the vast majority of homes. They
considered 2, and rejected it.
* Title III of the Toxic Substance Control Act, 15 USC 2665.
Signed by President Reagan, by the way!
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That same contractor
gives a lifetime warranty. Why don't you?
Again, it's easy to make promises, especially vague ones like that.
(Whose lifetime? Yours? His? His company's?) Our performance
guarantee is 10 years, and our warranty is 5 years a time period
chosen to be longer than just about anything else in your house, yet
still unambiguous and legally enforceable. National surveys of
EPA-listed companies have shown that the typical radon system
warranty runs from 1 to 5 years. We are way beyond the average.
Ask yourself how long that person is likely to be around. Better
yet, ask the Better Business Bureau.
One other thing -- it's easy to make promises if nobody will be
checking up. We make it easy for our customers to monitor the system
performance, by offering the plug-in radon monitor/alarm. We want
you to have complete confidence and peace of mind, and if you
entrust your family's health to us, we'll do whatever we can to give
you that assurance.
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Why don't you run a
test after the work? Your competitor does.
Ask yourself why a contractor would want to run the
post-mitigation test himself. Either he's not sure of his work, or
he doesn't want a third party involved.
There's an obvious conflict of interest when the radon contractor
determines the effectiveness of his own work. Because of this, the
EPA requires the contractor to recommend a third-party test of some
kind. Some states go further, allowing the contractor to do tests
for his own purposes, but prohibiting him from reporting the results
to anyone else.
Professional Decontamination Services, LLC always include a
mail-in test kit. [AirChek brand, the same kit you could purchase
from the county health department.] The user breaks the laboratory
seal on the packet, conducts the test, mails it off and receives
results directly from the lab to whatever address he may specify. We
are hands-off through the entire process.
- We know that time is important, so we have made special
arrangements with AirChek for priority handling. Our website
also has a
window into their database; if you know your test kit
number, you can see the result within about 12 hours after it
reaches the lab.
Even where the contractor has guaranteed his system, a home
seller still has an inherent interest in producing a low
post-mitigation radon reading. Unavoidably, that also creates a
conflict of interest with the buyers. Bottom line -- in a real
estate transaction the buyers are better off doing the test
themselves, when they are in control of the test conditions.
Please understand that (unlike many contractors) we are in fact
EPA/NEHA-certified for radon testing, and also have the specific
certification that allows using electronic monitors. We do offer
such a test when the client needs a certified test report ASAP to
support the closing or satisfy a relocation company. And we may also
conduct a diagnostic test in those rare cases when we're not certain
that the system will work the first time. However, in both those
situations, we consider our test to be supplemental to the mail-in
kit third party test.
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Questions about Radon Testing
Why test in the
basement? Nobody in our family spends any time there.
The EPA specifies testing in the basement because it is [almost]
always the worst case, and the next people to live in the house
might use it differently. Of course, if it's a Michigan basement
that could not easily be converted to living space, the test should
be done on the living areas.
There's another reason, too. Basement air is the most stable, and
if we know the radon level in the basement we can make a pretty good
estimate of what it will be on upper floors. With a typical home and
forced air heating, radon levels on the upper floors will be [very
roughly] about 40% less than in the basement.
Surprisingly, we find
that the second floor typically has more radon than the first; this
is because the "neutral pressure plane" is typically about halfway
up the wall on the top floor. Below that level, the house tends to
draw air in; above it the tendency is to exhale. Thus the basement
is drawing in radon, the first floor is drawing fresh air, and the
upper floor is receiving and expelling a mixture of the two.
By the way, if you let a skunk loose in your basement, you'd
smell it throughout the house. Don't for a minute think that the
radon is only in the basement.
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Why bother paying extra
for a professional to do radon testing?
If you are buying a home, it's important to remember that
you are not in control of the property, and you need all the help
you can get to be sure that the test conditions were properly
maintained. A pro will know how to deploy the radon detector(s),
will use security seals and other methods to tell if windows had
been opened, and will deliver you a certified report that has legal
standing. If the tester is state-licensed or NEHA-certified, you
also know that he has a formal quality assurance program and
subjects his records and his knowledge to periodic audit.
We are frequently called in to pick up the pieces after the home
buyer or seller has learned that the test was not done properly.
Often the first inkling they may have is when they call us to fix a
supposed radon problem, and we begin inquiring about the test or
refer them to the State of Georgia Radon Office (1-800-RADON GAS).
The most common deficiencies or outright errors we find in real
estate transactions are:
- In cases where the test device does not produce a datatape
with hourly readings, EPA protocols require that two detectors
be employed. If you did not receive a datatape with your test
report, you should see two radon readings and an average. Only
one? Unfortunately, you paid for a radon test, but only got half
a test. Do not take action based on this half-test.
- Protocols require that the "closed house conditions" be
maintained for 12 hours before the test, and for at least a 48
hour test period. Competent professionals will use various
methods to ensure that these conditions were achieved.
Frequently we find that an inexperienced and uncertified tester
didn't even inform the homeowners that this was expected.
- Test devices are sometimes placed in inappropriate locations
where they will give false readings -- sometimes high, sometimes
low.
- Some monitors are improperly calibrated or have calibrations
grossly out of date.
We don't always know what to do when faced with one of these
situations. Often the sellers, afraid of the deal falling through,
will just accept an improperly run test and shell out the money to
"fix" what amounts to a non-problem.
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Why do I have to keep
the upstairs windows closed during the test?
The short answer is that the protocols require it. The complete
answer is that your house is acting like a giant chimney, with warm
air rising and escaping out the top, drawing replacement air in from
the lower level(s). Thus, if you open upstairs windows you are
adding to the "stack effect," probably causing the radon levels in
the basement to increase.
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Where is the best place
in the basement to set the test?
All other things being equal, we would place the test in a finished
area where people are most likely to be spending time and inhaling.
Be suspicious of a tester who places the detector close to the sump,
which is (a) likely to be a major radon entry point, and (b) not
likely to be where people would spend much time. Be especially
suspicious if the tester is also someone who does radon fixing.
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I've heard that radon
levels change from day to day. What's the point of a test?
It's true. Radon levels are strongly influenced by wind, barometer
changes, precipitation and temperature. A skilled tester will be
able to help you sort through all these variables and advise whether
a long term test is needed
If you are buying or selling a home and want to minimize your
risk and hassle, you may wish to consider an UnTest instead of an
inherently uncertain short term radon test.
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What's a long term test?
How long is it? What is the cost?
The EPA defines a long term test as one that runs for at
least 90 days, and preferably for a full year. Ideally, the weather
conditions should represent a balance of warm and cold weather, i.e.
with an average outdoor temperature equal to the annual average.
Cost of an alpha track test kit is about $45 including lab fees.
These are probably available from your county health department, and
definitely from us. In either event, the lab sends the test report
directly to you.
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The house was closed up
for approximately a month before the test, so the reading is too
high. Isn't it?
Sorry. Radon levels stabilize within about 12 hours. That's why the
EPA requires a 12 hour period of "closed house" before the test
begins. There are two factors at work. First off, radon is
radioactive (otherwise we wouldn't be having this conversation),
which means that it is breaking down continuously. If I had a bottle
containing 1 pound of radon (very large bottle), in 82 hours (3.8
days) half of it is gone, transformed into other elements --
bismuth, polonium and lead. Another 82 hours and we're down to only
1/4 pound of radon, and so on.
More importantly, a house is breathing (in at the bottom, out at
the top) even when it's closed up. A typical home will have at least
15 air changes a day in normal operation, and perhaps 8-12 when
completely closed up.
Bottom line -- the vast majority of the radon that's measured
entered the house during the test or in the preceding 12 hours.
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