The NRPB PADC neutron personal dosimetry service.

The UK National Radiological Protection Board has been operating a successful contract neutron personal dosimetry service based on poly-allyl diglycol carbonate (PADC, also known by the trade name CR-39) since 1986, covering about 1500 workers and serving major nuclear sites in the UK and abroad. In that time approximately 100,000 dosemeters have been issued. Since the service was launched, a number of aspects have undergone evolution and it is therefore worthwhile to give an updated summary of how the service operates and performs today. The description covers the choice of plastic and of etching technique, the design of the dosemeter, the features of the automated image analysis, and the characteristics of the control software. Also described are the approaches to calibration and traceability and to compensation for energy and angle dependence, with particular mention of the ability of the service to estimate the quantity Hp(10) in accordance with the requirements of the European Council Directive 96/29/Euratom.