Since the International Commission on Radiological Protection (ICRP) has issued in Publication 60 new recommendations on radiation protection quantities, there is increasing interest in commercially available instruments optimized and calibrated for the measurement of neutron ambient dose equivalent H*(10) (Conversion factors as published in ICRP74).

Therefore the neutron dose-rate meter LB 6411 was designed in a joint cooperation between BERTHOLD and the Research Center Karlsruhe. The detector system with integrated electronics has a patented He-3 proportional counter tube centred in a moderator sphere with a diameter of 250 mm. The geometrical arrangement was optimized with the help of extensive MCNP Monte-Carlo calculations and is patented too.