Abstract: The invention particularly relates to a facility for characterizing liquid-dissolved gas. In its most complete embodiment, this facility comprises a liquid collecting capsule (1) and a circuit of fluid with two branches (2, 3) including a plurality of valves (41-47), the first branch (2) making it possible to retain the liquid, and the second branch (3) making it possible to extract vacuum gases and including in particular a sealed joint section (31), a pumping facility (32), a variable volume enclosure (33), and pressure and temperature measurement means (34-37).