OSL with chips from US credit cards

Abstract

Chips from credit cards issued by the major US banks have been tested with optically stimulated luminescence (OSL) as potential materials for use in emergency radiation dosimetry. The following dosimetric properties have been studied: (1) OSL decay curves from both irradiated and unirradiated samples; (2) dose-response characteristics of the OSL and values of minimum detectable doses; (3) fading of the OSL signal with time after irradiation. No OSL was detected in unexposed samples while prominent signals were observed after irradiation. It was found that the shape of the OSL signals can be fitted by a combination of an exponentially decaying function and a power function. The dose-response relationship was linear in the range 0–7 Gy if the OSL signals were measured at the same effective time after irradiation and normalized to the response to a test dose. Dose recovery tests demonstrated that the doses can be reconstructed with an accuracy ±20% if the OSL measurements are conducted within 7 days after exposure and the corresponding OSL doses are corrected for fading.