Alpha particle emission from reference glass surfaces implanted with 210po

Implanted long-lived radon decay products in glass surfaces have been used as a measure of pastradon exposure in homes. Special track-etch devices (so-called retro-detectors") attached to the glasssurface, have the ability to specifically measure the implanted activity of 210Po in-situ. Calibratingthese devices for 210Po is fairly straightforward, but the retro-detectors are also sensitive to thebackground activity of the glass substrate. Thus, for the successful calibration of retro-detectors, it isnecessary to determine the complete alpha emission energy spectrum of the reference glass sheetutilized as a calibration pad. In order to achieve accurate knowledge of the alpha surface emissionrate, we have combined several different approaches, i.e. alpha spectrometry of the pad surface withboth surface-barrier and pulse-ionisation detectors, and activity determination of the glass matrix bymeans of radiochemical methods. The part of the alpha emission spectrum originating from the glassvolume is then calculated theoretically and compared with experimental results.