(n.) Well Testing. A state that a producing well reaches when the flow rate and well pressure are apparently constant for a reasonable period of time, such as a few hours or a day or more. The actual time period is rather arbitrary and depends on the location and the people involved. For shut-in wells, stabilization refers to a reasonably constant pressure. Stabilized pressures are commonly used as starting points for well tests. In reality, the time to stabilization at truly constant pressure and rate is infinite. The target stabilization for rigorous testing in gas wells is pseudosteady-state flow, and this may be recognized as the pressure change versus time predicted from formation properties and drainage area size. The onset of radial flow may produce an apparent stabilization that is acceptable for analysis when multirate flow periods are of equal duration. See: Flow-After-Flow Tests, Pseudosteady State