The electronic continuous radon monitor (CRM) gives hour by hour measurements of the radon levels in your home. The CRM equipment might look like the pictures below. Some equipment can determine if it is moved and may also measure temperature, humidity and barometric pressure which might indicate someone opened windows in the test area.

Radalink CRM

Pylon CRM

There are a number of qualified companies who can test your home with very accurate radon monitors. Visit PA DEP Radon website for a list of qualified testers. Click the PDF that is sorted by "County" and look up your county for local companies.

PA List of Certified Radon Companies

Hire a Professional Radon Tester who uses a

CERTIFIED PASSIVE RADON TEST

Some Professional Certified Testers may use passive detectors. The two commonly used types are charcoal detectors and E-PERMs.

Charcoal Detectors

E-PERMs

These detectors give the average radon levels over the entire exposure period. The E-Perm method will tend to give a more accurate average than the charcoal detectors but is only available when placed and retrieved by an E-PERM certified test technician

To order "do it yourself" test kits call:

ABE Radiation Lab (610) 756-4153

or order test kits online from:

Air Chek Test Kits and Homeradontest.com

LONG TERM RADON MEASUREMENTS

Most radon measurements are typically 2 to 4 days in length. You can also leave a radon detector in place for one month to one year. You need to expose one of the detectors pictured below to do a long term radon test.

RSSI ATD

Radtrak ATD

A Professional Certified Radon tester can install and retrieve these devices in your home for about $175 or you can purchase them your self. Air Chek Test Kits and Homeradontest.com sell the long term detectors for about $30.

Inexpensive Electronic Radon Monitor

You can purchase your own electronic monitor that can be used over and over in different locations. This unit does not have the sensitivity to measure radon levels every hour but it will give you the average radon levels over a seven day period. The data can be cleared and the unit moved to a different location to give the radon levels at that new location.

You can also purchase this Pro-Series 3 monitor for about $150 from
Homeradontest.com

Measuring Granite Flux

You can purchase granite testing kits from Homeradontest.com for measuring the radon emanation from your granite counter tops. If your counter top does emit significant radon, this test kit will detect it. Unfortunately, however, the emanation from a counter top will vary significantly across the surface and the coatings applied to the polished side can drive the radon out the un-polished side. Therefore this test can easily give wrong information about the radon emanation from your counter top.

If you are considering using this test please consult with Airchek first.

Before purchasing go to WPB Radon & Granite info for more detailed information

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Click - Frequently Asked Questions below for answers

Should I do another radon test?

Will rain during my radon test raise the level?

Can I do my own radon test?

Are electronic radon monitors more accurate than passive testers?

Are the Test Kits sold at Home Depot or Lowes any good?

What is a long-term radon test?

Should I test radon in water?

Does a vacant house have higher radon levels?

Can a person selling his home cause a radon test to pass?

Why are previous tests so different?

How is a mitigation system tested?

What is Thoron?

You can ask Bill any question by email: Bill's email

Should I do another radon test?

If only one radon test was done in your home it is generally recommended to make a second measurement before deciding on mitigation. Radon tests are easy and inexpensive. You can purchase test kits from these two suppliers: Air Chek Test Kits and "ABE" (610) 756-4153

If the home is in the midst of a real estate transaction then it is usually necessary to have a professional independent tester make the second measurement. You can, however, always test your own home. Note that a buyer may not accept test results made by a seller.

If the radon levels are greater than 10 pCi/l it is unlikely that the second test will be below the guideline. It becomes more prudent, however, to do a 2nd test the closer the first test is to the 4.0 pCi/L guideline. When radon levels are marginal or below the guideline it is recommended to test in an opposite season or do a long term test to better define the average radon levels.

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Will rain during my radon test raise the radon level?

Normal light rain does not generally raise the radon levels significantly. If there is continuous hard rain (more than 1/2") it can cause radon levels to rise in most houses and to fall in other homes when the rain causes the sump pump to run (The water under the basement slab can reduce radon entry). When you average the radon levels for the length of the test exposure (typically 2 to 4 days), the elevated radon levels during the rain period raises the overall average much less. If the radon test is done to determine if mitigation is necessary for a real estate transaction then prolonged rain and a borderline test (4 pCi/L to 6 pCi/L) may be a reason to retest.

Can I do my own radon test?

You can always test your own home even if it is involved in a real estate transaction. A new buyer, however, may only feel comfortable with a radon test done by a certified independent radon tester.

Are electronic radon monitors more accurate than passive testers?

Electronic radon monitors can be more accurate than passive test kits such as charcoal detectors or E-Perms. All radon test kits and monitors used in Pennsylvania must pass proficiency tests. Electronic radon monitors offer the advantage of measuring the radon levels every hour, which can indicate unusual radon patterns or possible radon test tampering.

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Are the Test Kits sold at Home Depot or Lowes any good?

The radon test kits commonly sold at local hardware stores, Home Depot and Lowes are OK. They do not have the accuracy of a professional electronic radon monitor but as a homeowner you primarily need to know does you house have very little radon, a moderate amount or a lot of radon. Day to day differences in weather and house activity causes a greater variation in radon levels than the variation from simple radon test kits. Ultimately the best method to determine your radon levels is to do more than one test.

What is a long-term radon test?

Short-term radon tests are generally 2 to 7 days in length. Short-term tests must be made with closed house conditions. A long-term radon test is three months to one year in length. Long-term tests do not require closed house conditions. If radon measurements during a real estate transaction are questionable, a long-term test is sometimes performed with money left in an escrow account to pay for a radon mitigation system if the long-term test results are above the 4.0 pCi/L guideline.

Should I test radon in water?

The EPA states in the Home Buyers and Sellers guide to radon , “If you have tested the air in your home and found a radon problem, and your water comes from a well, have the water tested.” Radon in water needs to be in the thousands to be a significant risk. One study indicated that about 1 in 20 wells in Pennsylvania will have radon levels of 3000 pCi/l or higher. For more information refer to the radon in water information page at: Radon in Water

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Does a vacant house have higher radon levels?

The upper floors of a vacant house will likely have higher radon levels than a similar occupied house if a normal occupied temperature is maintained. The basement ventilation level of a vacant house, however, is not likely to be significantly different than an occupied house and therefore is likely to be a similar radon level. Note that radon does not build up to higher levels the longer a home is vacant because of normal natural ventilation.

Can a person selling a home cause a radon test to pass?

Radon levels will change when you open a window especially if the window is in the same area as the test kit. In general however the window or multiple windows have to be wide open in the test area to make a big change (cut radon levels in half). If the radon levels are just above the guideline they can however be reduced below the guideline by opening windows. Opening windows on floors above the area being tested can cause the radon levels to go either higher or lower. Moving the radon detector to a low radon area will obviously also change the results to the new location level but many testers will minimize this possibility with tamper resistant features. We have a full report on test tampering available as a download.

Why are previous radon tests so different?

Some difference is expected because radon levels fluctuate due to weather and house conditions. It is not un-common for radon levels to be twice as high or one half of previous measurements. Upstairs measurements in particular can be significantly different in heating versus cooling seasons. Basement measurements tend to be more consistent in different seasons. A basement measurement that is ten times higher or one tenth of a previous measurement would be unusual.

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How is a mitigation system tested?

The PA DEP and the EPA RMS requires a post mitigation radon test be completed within 30 days after the mitigation system is activated. It is advisable to have an independent certified tester perform the test for all real estate transactions

What is Thoron?

Thoron is a common radioactive element found all over the world that is also a noble gas like radon. It is typically not a problem in homes because it has a very short half life (55 seconds). This short half life does not allow enough time for thoron to typically escape into the air of a home. See lots more info on Thoron here.

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You can ask Bill any question by email: Bill's email