Tag Archives: radon

Radon Measurement

The only thing Continuous Radon Monitors (CRM) do continuously is power their timers. “Why is that?”, you say. CRM timers tell the machines when to sample for Radon. Yes, that’s right, I said, “sample.”

Some popular machines only sample once every hour, others once every half-hour. Either way the most readings your getting over a 48 hour period is 96! The average of these samples is your result.

Everyone knows that the more samples you have the better their average represents the actual quantity.

The only way to get a truly continuous result is if you have a chemical reagent that changes over time. Film and photo papers are good examples of this. Exposure to light changes them over time.

Two Radon Measurement technologies exist that do just this. Each gradually changes over time when exposed to Radon continuously. The sample is the entire 48 hour time commonly allowed of Radon measurement for Real Estate transactions.

The most consistently accurate of these two are charged electrets. An electrical charge is placed on two electrets and measured before exposure to Radon. After the exposure time is complete (48 hrs.) they are measured again. Because the charge decays in the presence of Radon, the difference in readings will accurately measure the quantity of Radon in the home.

Radon equipment should be calibrated annually. Measurement should be done in the lowest livable level of the home. If the buyer intends to finish the basement it should be done there.

Your report should tell you where in the home the measurement was taken, the final result, and the equipment calibration date. The equipment calibration date should never be more than one year from the test date. This assures you that equipment maintenance is up to date.

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National Radon Action Month – January

January is National Action Month for Radon Awareness.  Do you know the Radon levels in your home?  Do you know the effects of long term exposure to you and your children.

Independent Home Inspection is offering a 20% reduction in our fee for Radon tests with or without a home inspection.  This includes testing those homes that already have a Radon mitigation system.  Testing homes with mitigation systems installed insures their continued effectiveness at reducing Radon to safe levels.

You’re wise to check your new home for Radon before you buy. The EPA says all homes can have Radon. This includes new homes as well as older homes. No mitigation systems installed in your neighborhood may simply mean those homes haven’t been tested.

So, what results do you need to make a decision about Radon levels. The answer is simply the average concentration over the testing period. This includes short term tests, as in a Real Estate transaction, or long term tests that might be done to monitor the effectiveness of an installed mitigation system. The EPA has set 4.0 piCul as the action level for a single family home. At or above that level requires a mitigation system to reduce harmful Radon levels.

Independent Home Inspection uses an electret based Radon monitoring system to measure your homes Radon level. Electrets have an initial electrical charge that decays at a known rate in the presence of Radon. I use annually calibrated equipment to measure the electret charge before and after exposure and a computer generates the result on the basis of the measured differences.

Electret systems advantages are many. They require no power source during testing. They continuously respond to Radon exposure rather than sampling (other methods sample hourly or ½ hourly). Results do not require a lab and accurately indicate the Radon average over the testing period. In fact this method of Radon testing has been determined to be the most accurate system available today.

Independent Home Inspection is available to test your homes Radon either with a home inspection or alone. Call or text today for availability and cost: 410-504-3751

www.IndependentHomeInspectionMD.com

Montgomery County Radon Law

Montgomery County Bill 31-15 will take effect on October 1st of this year requiring radon testing for certain residential Real Estate transactions.

In an article published last fall the ‘Bethesda Beat’ discusses some of the ramifications of this bill.

The article erroneously suggests, however, that radon test kits can be had for as little as $15-25 at hardware and lumber stores. Had the authors taken the time to actually read the instructions with these kits, they would have known that an additional $50-75 fee is necessary to submit these kits to a lab by mail.

For a Real Estate transaction the time required to test and mail the kits may not accommodate the settlement schedule. Radon Testing for a Real Estate transaction will require a minimum two day (48 hour) short term test. A professional Radon Testing company, like myself, can provide results the same day that testing concludes.

Bob Kenney
Independent Home Inspection