How to Test Your Home for Radon A Beginner’s Guide

To test your home for radon, choose a suitable test kit or electronic monitor, follow the relevant placement and testing instructions, and compare the completed result with local guidance. The correct procedure depends on where you live and why you are testing.

This guide explains the decisions to make before starting. It does not replace a device manual or a formal property transaction testing protocol.

Step 1 Identify the purpose of the test

Are you measuring everyday exposure in your own home, checking a newly used basement room, or arranging a test for a property sale?

Write down the purpose before selecting a device. A home monitoring product is not automatically accepted for a regulated inspection or transaction report. If a report is required by another party, confirm the measurement method and provider requirements first.

Step 2 Check the guidance for your country

Testing periods are not identical worldwide.

Do not shorten a test because an electronic monitor has started displaying numbers. The first reading and a completed measurement answer different questions.

Step 3 Choose a suitable kit or monitor

A passive kit can suit a defined measurement period, with analysis handled according to the kit instructions. An electronic monitor can make it easier to observe readings and averages while it remains in place.

Check performance evidence, power requirements and the instructions for your chosen product. In Canada, Health Canada advises purchasers of electronic radon monitors to choose a model that has passed C-NRPP performance testing for long-term residential measurements. [4]

For a fuller comparison, read How to Choose a Radon Detector for Your Home.

Step 4 Select the location before starting

Choose a room and level according to your local protocol and measurement purpose. US residential guidance commonly focuses on the lowest lived-in level; property transaction guidance may consider the lowest level suitable for occupancy. Do not assume the same room rule applies everywhere.

Avoid placing a device wherever it is easiest to see without checking the instructions. Drafts, heat, humidity and disturbance can make a location unsuitable. US guidance includes keeping the device at least 20 inches above the floor, but other clearances and room-selection rules must also be followed. [5]

Record the room, position and start date. A quick placement photograph can help you keep a consistent record.

Step 5 Maintain the required test conditions

Some short-term protocols require closed-house conditions before and during the test. That does not mean you should apply the same restrictions throughout every long-term measurement.

For Canadian long-term residential measurements, Health Canada advises occupants to maintain their normal lifestyle. Follow the instructions for your particular test rather than mixing short-term and long-term procedures.

Leave the detector in its chosen location. Check power or battery status where applicable, and follow any return or laboratory submission deadline for a kit.

Step 6 Read the completed result in context

Check the unit, the averaging period and whether the test met the required conditions. Keep those details together with the result.

As a US example, EPA recommends fixing homes at 4 pCi/L or above and considering reduction between 2 and 4 pCi/L. These are action recommendations, not a promise that lower exposure is risk-free. [6] Use the relevant national guidance when testing elsewhere.

An elevated reading deserves follow-up. If a result is very high, contact your local radon programme or a qualified professional promptly rather than waiting for a generic testing schedule to finish before asking for advice.

Step 7 Keep records and plan follow-up

Save the completed result and any professional report. Follow-up testing may be appropriate after mitigation, major building changes or a change in which rooms are occupied. [7]

For the underlying concepts, read What Is Radon? If you are using a general air quality monitor, check Can an Air Quality Monitor Detect Radon? before relying on it for this task.

Frequently asked questions

Can I move one monitor between rooms every day?

Not during a test intended to represent one location over a defined period. Follow a planned room-by-room approach or use additional devices when required by the protocol.

How quickly will an electronic monitor show a result?

That depends on the model. Check its initial reading time and averaging periods. A displayed number does not shorten the recommended measurement duration.

Can I test a home without a basement?

Yes. Select the appropriate room and level under the applicable guidance; a basement is not a prerequisite for testing.