ASTM D4628-97

1.1 This test method is applicable for the determination of mass percent barium from 0.005 to 1.0%, zinc, calcium, and magnesium from 0.002 to 0.3% and zinc from 0.002 to 0.2% in lubricating oils.

1.2 Higher concentrations can be determined by appropriate dilution. Lower concentrations of metals such as barium, calcium, magnesium, and zinc at about 10 ppm level can also be determined by this test method (Note 1).

Note 1- Use of this test method for the determination at these lower concentrations should be in agreement between the buyer and the seller.

1.3 Lubricating oils that contain viscosity index improvers may give low results when calibrations are performed using standards that do not contain viscosity index improvers.

1.4 The values stated in SI units are to be regarded as the standard.

1.5 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. Specific precautionary statements are given in Notes 1, 2, 6 and 8.