Historical
ISO 4548-9:1995
Methods of test for full-flow lubricating oil filters for internal combustion engines -- Part 9: Inlet and outlet anti-drain valve tests
Specifies methods of measuring the effectiveness of either inlet or outlet anti-drain valves if fitted to a full-flow lubricating oil filter of the "spin-on" or "easy change" type, for internal combustion engines.
International Organization for Standardization [iso]
