Determining dose equivalent rate and other neutron radiation characteristics by NB 52U1 and NB 5201A monitors

Neutron monitors NB 5201 and NB 5201A are portable radiometric instruments for monitoring reactor, accelerator and neutron generator sites and the immediate vicinity of isotope sources for the purposes of personnel protection. They use the principle of neutron moderation and are individually calibrated using a 241Am-Be source whose neutron flux was determined with an accuracy of +-2%. The design of the monitors is described. In addition to the evaluation of dose equivalent in the range of about 0.01 mSv/h to 100 mSv/h for neutron energies from 0.025 eV to 14 MeV, the NB 5201A monitor allows determining the physical characteristics of neutrons at a chosen point, ie., the dose rate, kerma and fluence. The monitor specifications are given. Series production is to be started in 1982. (J.P.)