A neutron detection apparatus is provided which includes a selected number of surfaces of lithium-6 coated wire mesh and which further includes a gas mixture in contact with each sheet of lithium-6 coated wire mesh for selectively reacting to charged particles emitted or radiated by the lithium-6 coated mesh. A container is provided to seal the lithium-6 coated mesh and the gas mixture in a volume from which water vapor and atmospheric gases are excluded, the container having one or more walls which are transmissive to neutrons. Monitoring equipment in contact with the gas mixture detects the generation of charged particles in the gas mixture and, in response to such charged particles, provides an indication of the flux of neutrons passing through the volume of the detector.