AN ADVANCE IN EPR DOSIMETRY WITH NAILS.

Olive oil is proposed as a medium for storage of nails in the time between nail harvesting and electron paramagnetic resonance (EPR) measurements to minimise the decay of the radiation-induced EPR signals (RIS). The behaviours of three main EPR signals, namely, RIS, mechanically induced and the background signals (MIS and BG, respectively), were studied for storage in olive oil. The properties of the MIS and BG signals were very similar to those previously observed for the storage in a vacuum. The RIS singlet slightly increased during the first day of storage and then remained practically unchanged at least for 6 days. Dose recovery test revealed that doses at the level 2 Gy may be reconstructed with an accuracy of about +/- 20%.