Neutron Under Water Coincidence Counter (IAEA)

ANTECH N2106 Neutron Underwater Coincidence Counters (UWCC’s) are used to measure neutron radiation activity from spent
fuel assemblies. They are supplied in one of two configurations;

• PWR, used to measure Pressurised Water Reactor fuel rods
• BWR, used to measure Boiling Water Reactor fuel rods.

PWR fuel rods are larger than BWR rods. Therefore, the PWR configuration detector has a larger detector head than the BWR. These are the only differences; all other components are identical. The detectors are designed to be portable and easy to assemble to
facilitate transportation between sites and quick se-up to conduct measurements.

Detector efficiencies of 2-4% (typical) are attainable dependent on the detector type and geometry.

Each system consists of a detector head with integral electronics, a set of connection pipes with associated interconnect clamps, O-ring seals, interconnect cables, a mechanism for attaching the detector assembly to the pond gantry side rails and an OR Box, which combines two input signals from the three detectors in each tine of the fork of the detector head into a single output signal, that is ultimately fed into counting electronics such as an ANTECH N2000 Universal Neutron Counter, or MicroMesskanal or JSR 15.
Each detector is supplied with full documentation and test records including a leak test report, Certificate of Conformance and manufacturers test records for preamplifier and ³He tubes.