What to Expect During a Radon Test

If you've never had your home tested for radon before, the process is simpler than most people expect. Here's a clear walkthrough of what a short-term radon test involves.

The Two Types of Tests

There are two main approaches to residential radon testing: short-term and long-term. Short-term tests take 48–96 hours and give you a quick baseline reading. Long-term tests run 90 days or more and give you a more accurate picture of your home's annual average.

For most initial screenings — including real estate transactions — a short-term test is the standard approach.

How the Devices Work

Most professional short-term tests use electret ion chamber (EIC) devices or activated charcoal canisters. The tester places one or more devices in the lowest livable area of your home — typically the basement, or lowest floor if no basement.

The devices passively collect radon gas from the air for the duration of the test. After the test period, they're sent to an accredited laboratory for analysis. Results are typically available within 24–48 hours of the lab receiving the sample.

What You Need to Do

Your role during the test is straightforward. The most important requirement is maintaining closed-house conditions:

• Keep all windows and exterior doors closed except for normal entry and exit
• Do not run fans that exhaust air outside (bathroom exhaust fans are fine)
• Continue normal use of the home — you don't need to leave
• Do not move the test device
• Avoid heavy smoking near the device

After the Test

Once the tester retrieves the device and the lab returns results, you'll receive a report showing your radon level in picocuries per liter (pCi/L). The EPA recommends mitigation for any reading at or above 4.0 pCi/L.

If your results show elevated levels, that's when a mitigation specialist like ARS comes in. We design and install the system that brings your levels down — typically in a single day.