ResourcesGlossary: testing
Continuous radon monitor
Short answer
A continuous radon monitor is an electronic test device that measures and records the radon in the air again and again through the test, instead of giving one total at the end. EPA classes it as an active device: it needs power to work.
What continuous radon monitor means
EPA describes what you get from one: active radon testing devices usually provide hourly readings and an average result for the test period.
For a home sale, one of the test options EPA gives is to test the home with a continuous monitor for at least 48 hours.
How many readings an hourly monitor takes
Each row multiplies the days of the test by 24 hourly readings.
| Length of test | Days | Hourly readings |
|---|---|---|
| EPA's 48-hour minimum | 2 | 48 |
| One week | 7 | 168 |
| The shortest long-term test | 91 | 2,184 |
What it means for your home
The hourly readings come with an average for the test period, and the average is the number to hold against EPA's 4
For a home sale, EPA recommends that the test be conducted by an independent, qualified radon tester.
Where to go next
- Which radon test to use. See whether a monitor, a kit or a professional test fits your situation.
- Professional radon monitors. The instruments testers use, and how they differ from home monitors.