1.1 This test method covers the determination of ash in the range 0.001-0.180 mass %, from distillate and residual fuels, gas turbine fuels, crude oils, lubricating oils, waxes, and other petroleum products, in which any ash-forming materials present are normally considered to be undesirable impurities or contaminants (Note 1). The test method is limited to petroleum products which are free from added ash-forming additives, including certain phosphorus compounds (Note 2).

Note 1—In certain types of samples, all of the ash-forming metals are not retained quantitatively in the ash. This is particularly true of distillate oils, which require a special ash procedure in order to retain metals quantitatively.

Note 2—This test method is not intended for the analysis of unused lubricating oils containing additives; for such samples use Test Method D874. Neither is it intended for the analysis of lubricating oils containing lead nor for used engine crankcase oils.

1.2 The preferred units are mass %.

1.3 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.