CURRENT STATUS OF AN ISO WORKING DOCUMENT ON REFERENCE RADIATIONS - CHARACTERISTICS AND METHODS OF PRODUCTION OF SIMULATED PRACTICAL NEUTRON FIELDS

The International Organization for Standardization (ISO) TC85/SC2/WG2 has convened a working group to develop a standard dealing with the pr oduction, characterisation and use of reference neutron radiation fiel ds simulating those found in the workplace. This standard is being dev eloped to provide guidance to the laboratories developing simulated pr actical reference neutron fields, and to the users of these fields. Th e ISO currently recommends four reference neutron spectra for the cali bration of radiation protection instruments and dosemeters. However, d ue to the energy dependence in the dose equivalent responses of these devices, it is useful to develop additional neutron spectra for calibr ation purposes. This standard will describe the methods of production and the expected characteristics of simulated practical neutron fields . The types of facilities considered include those using radionuclide neutron sources, accelerators and reactors. Facilities producing high energy neutrons for the calibration of instruments and dosemeters used at accelerator laboratories and in aircraft for in-flight monitoring are also considered. The status of this standard is being presented no w in order to provide a progress report and to elicit comments and sug gestions before the standard is finalised.