Borderline pumping temperature is a measure of the lowest temperature at which an engine oil can be continuously and adequately supplied to the oil pump inlet of an automotive engine.

1.1 This test method covers the prediction of the borderline pumping temperature (BPT) of engine oils through the use of a 16-h cooling cycle over the temperature range from 0 to −40°C.

1.2 Applicability to petroleum products other than engine oils has not been determined.

1.3 This test method uses the millipascal (mPa·s), as the unit of viscosity. For information, the equivalent centipoise unit is shown in parentheses.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.