AbstractOGMS, the OutGassing Measurement System, is a facility to measure the outgassing rates of materials. The rate is highly important factor in vacuum science dealing with systems working at pressures below 10-6 mbar. In ultra- high vacuum range it plays role in system pressure at given pumping speed. For standard materials the data is available in literature but at times not under condition of specific application. Many application use very specific materials under vacuum conditions. Cryoadsorption Cryopump a project at Institute for plasma Research uses steel samples coated with activated carbon as sorbents. Various kinds of sorbents were used. Necessity to measure the outgassing rate of such unique materials established the OGMS. The OGMS facility has a known conductance of 2.46 l/s and base outgassing rate of ∼ 3x10-12 mbar-ltr/s-cm2. An ultimate vacuum of < 5 x10-9 mbar was achieved in a sample chamber of volume ∼7.5 liters. This paper describes OGMS, its calibration, experiments to find outgassing rate of steel samples and comparison with reported data to establish authenticity for new materials. It also reports results of outgassing rates of cryo-adhesives and activated charcoal coated steel samples.