Division 4.12.4
A non-return valve, when in the closed position, shall not leak when subjected to any aerostatic pressure between 50 kPa and its Maximum Allowable Working Pressure (MAWP).
A non-return valve, when in the closed position, shall not leak when subjected to any aerostatic pressure between 50 kPa and its Maximum Allowable Working Pressure (MAWP).