FURTHER STUDIES ON AGEING AND FADING OF CR-39 PADC TRACK DETECTORS USED AS AIR RADON CONCENTRATION MEASUREMENT DEVICES

PADC detectors are commonly used both as radon detectors and as personal dosemeters for neutron radiation. In both cases the measurement in workplace fields are characterized by long term irradiations, lasting up to several months. During this period the detectors undergo to uncontrolled and unmonitored environmental conditions. In a recent work the same authors demonstrated that the environmental conditions, mainly temperature, can seriously affect the detector sensitivity. The temperature effect is to reduce the V ratio by decreasing the track etching velocity Vt. This causes a decrease in limit angle and efficiency. This paper describes the same ageing / fading test made with CR39 from a different supplier. In this case it seems that the temperature has a negligible effect, so no compensation algorithm is needed.