Frequently Asked Questions

By regulation, radon fans must be located outside of the conditioned space of the home.

The regulation stipulates that the exhaust must extend above the roofline. 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.

As long as the system is running, the air exiting the pipe keeps rain and bugs out. The system exhaust must be vertical, and upward. The rest of the system is designed so that it pitches back down toward the suction point, so that any water in the system drains back into the soil. Caps and other diverters can cause freeze-up problems from condensation when it’s cold out. Did you know: radon systems can expel hundreds of gallons of water vapor each year?

PVC piping is the most suitable material for the job. Metal downspouts are not intended to be used for gas exhaust applications, and the joints cannot be permanently sealed (they require frequent re-sealing). Downspouts also tend to ice up in the winter, disabling the system just when you need it the most.

Our standard sump covers are transparent, so you can shine a flash light into the sump pit to verify that the sump is working.

The idea is to put a vacuum on the draintile that surrounds the foundation. The builder put it there to collect water, but we can use it to collect gas too. Because the draintile 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 draintile and then into our radon piping. Instead of passing through the house, they are confined to a small tube. Elegant.

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 draintile dry. If the draintile 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.

How much good news can you stand? In our experience (valid for Michigan, at least), 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. More than 10,000 successful systems so far.)

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. Here are two exercises for you:
Check out our 20 or 30 most recent test results using the window into Air Chek's database, and see how many times a value below 2 is listed. (Don't be scared off by the occasional high number; these are almost always pre-mitigation screening tests.)
Check out the credentials and track record of the Company making the promises. Some companies will simply walk away (and hopefully return your money) if they can’t fix your home. What happens if your home is one of the tough ones?
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!

National surveys of EPA-listed companies have shown that the typical radon system warranty runs from 1 to 5 years. Lifetime warranties are often vague or misleading (the lifetime of the fan, system, homeownership, the company, etc?). Keep in mind that radon can change based on changes you make to your home, and that the typical life expectancy of the radon fan 9the only motorized component of the system) is 5-10 years, and most manufacturers only warranty them for 5.

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.

Protech's mitigation systems 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.

Years ago, when turnaround times for mail-in kits were measured in weeks, our contracts always included a post-mitigation test performed with an electronic monitor. However, now that you can get results in a few days, mail-in kits are finally practical for real estate transactions, and our supplemental test is seldom needed.

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.

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 Michigan 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.

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.

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.

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.

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. Click here for a handy test planner that will calculate the optimum 'begin' and 'end' dates for you.

Cost of an alpha track test kit is about $25 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.

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.