ASTM D 7040 : 2026

1.1This test method covers the quantitative determination of phosphorus in unused lubricating oils, such as International Lubricant Standardization and Approval Committee (ILSAC) GF 4 and similar grade engine oils, by inductively coupled plasma atomic emission spectrometry.

1.2The precision statements are valid for dilutions in which the mass % sample in solvent is held constant in the range of 1 % to 5 % by mass oil.

1.3The precision tables define the concentration ranges covered in the interlaboratory study (500 mg/kg to 800 mg/kg). However, both lower and higher concentrations can be determined by this test method. The low concentration limits are dependent on the sensitivity of the ICP instrument and the dilution factor. The high concentration limits are determined by the product of the maximum concentration defined by the linear calibration curve and the sample dilution factor.

1.4The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.5This 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.6This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.