The KFA Counter, its Photon and Neutron Responses and its Potential for Future Developments

The KFA counter, an area dose equivalent meter based on a low pressure tissue-equivalent proportional counter (TEPC), was optimised with regard to its wall thickness so that the dose equivalent reading matches ambient dose equivalent, the operational quantity recommended for radiation protection, in the neutron energy range between thermal and 20 MeV. The calculations and measurements that were performed for the optimisation are summarised. The significance of the results is discussed with respect to both ambient dose equivalent and effective dose equivalent, the limiting quantity in radiation protection.