Emergency EPR dosimetry technique using vacuum-stored dry nails

Human finger- and toenails have been tested with an X-band EPR technique for different conditions of nail storage. The main radiation-induced signal at g = 2.005 demonstrated good stability if the samples were stored in a vacuum at room temperature after nail harvesting and irradiation. On the basis of this phenomenon, a new protocol is proposed to use the nails as possible emergency EPR dosimeters. The dosimetry protocol was tested on laboratory-exposed samples and demonstrated the ability to recover doses in the region 0–10 Gy with an estimated uncertainty of approximately 0.3–0.4 Gy for doses in the range <2 Gy, increasing to 0.6–0.7 Gy for doses in the range 5–10 Gy. - Highlights: • A dry storage technique for EPR dosimetry of finger- and toenails is introduced. • The main EPR signals from nails are isolated and their stability is determined. • Uncertainties are of the order of ∼0.5 Gy for the dose range 0–10 Gy.