TECNORAD uses electret as integrated system to measure gas radon in the short term and for precautionary map before annual concentration measurements. Electret ion chamber consists of a stale electret mounted inside an electrically conducting chamber, that permits the entrance to radon gas only.
The electret serves both as a source of electric field and as a sensor. The ions produced inside the chamber by radiation are collected by the electret. Once radon gets inside the chamber, after the decay, alpha particles reduce the electrostatic potential of the disk. In this way measuring the difference of the disk pre and post exposition using a special reader it is possible to discover radon concentration using appropriate