The E-PERM® System


Using electret ion chamber methodology is both extremely accurate and highly cost-effective. On average, you will spend less than $2 per radon test.

Versatile & Accurate

The E-PERM® System is the most versatile radon measurement system in the market, able to conduct both short-term and long-term tests in a wide range of environmental conditions. Electret ion chambers are true integrating devices, meaning that they do not bias their results toward the end of a measurement period.

Tons of Research

Rad Elec has been in business for over 25 years, and during this time has seen nearly a hundred academic and research articles published about our electret ion chamber technology. The E-PERM® System is tried and true, and continues to stand the test of time.


With the E-PERM® System, you finally have the freedom to analyze your own results. You never have to mail your detectors to an external laboratory in order to get them analyzed, which means that you can deliver reports to your clients on the same day that you retrieve the test.

Quick Links

Online Store

With Rad Elec's Online Store you can shop for your E-PERM® products at any time.

Quick Calculator

Analyze your radon test results in a flash with our online Quick Calculator.

Research & Publications

Explore our library of articles and publications involving electret ion chambers.

Frequently Asked Questions

Find answers to your most common questions right here.

Manufacturer Certified Users

The Manufacturer Certified E-PERM® User Certificate is issued only to individuals that have passed Rad Elec's equipment training course and adhere to the manufacturer's specifications of annual equipment maintenance and spiking.

YouTube Channel

Check out our latest videos and tutorials on Rad Elec's YouTube channel!