Non-intrusive verification procedures by measuring nuclear radiation in situ are discussed. Radiation measurements are decisive to prove compliance with nuclear arms control and non-proliferation in case suspicions arise at a definite locality. For that purpose we have set up a mobile measuring unit with high resolution Gamma-detectors and sensitive neutron detectors. Detection and identification of special nuclear material is performed by non-destructive and non-contact analysis. Importance is set to the demand that systems should limit access to sensitive information, so they can be applied by NNWSs (Non Nuclear Weapon States). In addition active neutron interrogation is employed for confirmation of the existence of fissionable material. The capability and limits of these systems and procedures are discussed and an outlook to future developments in new detection systems and procedures is presented. In addition such systems and methods may be used in combating transnational nuclear terrorism and asymmetric warfare.
