This part of ISO 4548 specifies a method of testing the ability of full-flow lubricating oil filters for internal combustion engines to withstand an internal pressure surge such as occurs when an engine is started from cold, and cyclic internal pressure variations experienced during operation. These tests are intended for application to spin-on type filters and detachable filters with disposable elements with a maximum flow rate of 100 l/min. The tests can be applied to other filters, if thought applicable, by agreement between the filter manufacturer and the purchaser. NOTE This test is not intended to replace simulated environmental testing (e.g. at very low temperatures). If such testing is required, it will be the subject of negotiation between the supplier and customer.