ACCIDENT DOSE ESTIMATION USING PORCELAIN - A COMPARISON BETWEEN DIFFERENT THERMOLUMINESCENCE METHODS

Accident dose estimation using the pre-dose technique on the 110 degre es C peak in porcelain has been used since 1984. The disadvantage of t his technique is that the reservoir traps appear to begin to saturate for doses around 1 Gy. This has limitations in regions of high fallout doses such as the contaminated settlements in the Chernobyl Exclusion Zone with fallout doses often above 1 Gy. When doses are added to mea sure the growth curve the total absorbed dose falls into the saturatio n region. Samples of porcelain fitments were collected from such settl ements and it was observed that the 230 degrees C peak in the thermolu minescence (TL) glow-curve for some of them was strong enough to carry out the simple additive dose procedure. In addition, the 230 degrees C peak pre-doses in a similar way. This enabled us to carry out three dose evaluations on each sample. It was observed that both pre-dose ev aluations yielded a similar result. The results of the simple additive dose in most cases are in agreement within error limits with the resu lts obtained using pre-dose techniques, although in some cases some di screpancies were observed. (C) 1997 Elsevier Science Ltd.