Many types of survey instruments for measuring exposure dose from neutrons and methods for assessing the dose equivalent rate have been developed in many countries. In JAERI, extensive efforts have been made for establishing the method to assess neutron dose equivalent.
The main objectives of this report are to introduce the principle of measuring neutron dose equivalent rate based on an orthonormal expansion method and to describe its application for the operational health physics in JAERI.
This report also describes an experience with the various types of neutron survey instruments which have been employed for the radiation protection in JAERI since 1958.