This part of ISO 12789 gives guidance for producing and characterizing simulated workplace neutron fields that are to be used for calibrating neutron-measuring devices for radiation protection purposes. Both calculation and spectrometric measurement methods are discussed. Neutron energies in these reference fields range from approximately thermal neutron energies to several hundred GeV. The methods of production and the monitoring techniques for the various types of neutron fields are discussed, and the methods of evaluating and reporting uncertainties for these fields are also given.