Beta radiation dosimetry with electrets

Cylindrical electret ion-chambers were used for detection and dosimetry of beta radiation and showed a linear decrease of electret charge with absorbed dose for different field geometries and wall materials. A beta secondary standard system was used with four beta sources (
⁹⁰
Sr
⁻⁹⁰
Y,
²⁰⁴
TL,
¹⁴⁷
Pm and
⁸⁵
Kr). Doses from 10
⁻⁶
Gy to 10
⁻¹
Gy can be measured with the system.