Construction details are given for a He gas scintillation neutron detector which operates to 238 atm at room temperature. A bakeable pressure‐vacuum manifold, on which the detector is evacuated and filled, also serves to remove contaminants from the DPS waveshifter. The detector appears stable when permanently sealed off. Curves are given for light output vs pressure, and some effects of impurities on such curves are noted. Measurements were made of relative sensitivity to60Co gammas and Pu‐Be neutrons. The gamma flux required to induce a current equal to that from 1 neutron/cm2sec is 15 MeV/cm2sec when the scintillating gas is4He, and 23 MeV/cm2sec when it is3He.