[en] This apparatus, a prototype of one being constructed for hotcell examination of irradiated nuclear materials, measures dynamic release rates and integrated volumes of individual gases from materials heated under controlled temperature-time programs. It consists of an inductively heated vacuum furnace connected to a quadrupole mass spectrometer. A computerized control system with data acquisition provides scanning rates down to 1s and on-line tabular and graphic displays. Heating rates are up to 1300⁰C/min to a maximum temperature of 2000⁰C. The measurement range is about 10^-6 to 10^-2 torr-liter/s for H₂, CH₄, H₂O, N₂, and CO and 10^-8 to 10^-2 torr-liter/s for He, Kr, and Xe. Applications are described for measurements of Kr and Xe in mixed oxide fuel, various gases in UO₂ pellets, and He in ²³⁸PuO₂ power and heat sources