NRPB PADC NEUTRON PERSONAL DOSIMETRY AFTER IRCP-60

The NRPB has been operating a routine neutron personal dosimetry servi ce based upon the electrochemical etching of PADC (poly allyl diglycol carbonate) elements since 1986. This service covers approximately 100 0 workers in the UK and abroad, requiring the issue of around 7500 dos emeters annually. It has performed relatively well in international in tercomparisons with samples taken from routine stock. The recommendati ons of ICRP 60 (International Commission on Radiological Protection, 1 991) may have serious consequences for many operational neutron dosime try services. The reduction in dose limits from 50 mSv to an average o f 20 mSv per year, the introduction of constraints and the requirement s for dose estimation in some circumstances down to a few mSv per year , inevitably result in a need to estimate lower doses with greater pre cision. Additionally, the proposed change in the Q(L) relationship to be applied in respect of the ICRU operational quantities will effectiv ely decrease the (dose equivalent) sensitivity of detectors.