ASTM D 5291:2026

1.1 The four test procedures (A, B, C, and D) addressed in this standard cover the instrumental determination of carbon, hydrogen, and nitrogen in laboratory samples of petroleum products and lubricants. Values obtained represent the total carbon, the total hydrogen, and the total nitrogen. 1.2 Test procedures A, B, and C are applicable to samples such as crude oils, fuel oils, additives, lubricants, and residues for carbon and hydrogen and nitrogen analysis. These test procedures were developed and evaluated in the concentration ranges of 75 % to 87 % by mass for carbon, 9 % to 16 % by mass for hydrogen, and <0.1 % to 2 % by mass for nitrogen. 1.2.1 Carbon, hydrogen, and nitrogen determinations can be made outside these ranges and other sample types can be analyzed but the precision statements (subsections 14.1 and 14.3 , Table 2), will not apply. 1.2.2 For nitrogen, the test procedures A, B, and C are not applicable to samples containing <0.75 % by mass nitrogen. 1.3 Test procedure D is applicable to samples such as lubricants and additives. The test procedure was developed and evaluated in the concentration ranges of 77 % to 85 % by mass for carbon, 12 % to 14 % by mass for hydrogen, and 0.10 % to 1.59 % by mass for nitrogen. 1.3.1 Carbon, hydrogen, and nitrogen determinations can be made outside these ranges and other sample types can be analyzed but the precision statements (subsections 14.1 and 14.3 , Table 2), will not apply. 1.3.2 For test procedure D, levels of nitrogen at 0.1 % by mass or higher can be determined in lubricants and additives. 1.4 These four test procedures (A, B, C, and D) are not recommended for the analysis of volatile materials such as gasoline, gasoline-oxygenate blends, or gasoline type aviation turbine fuels. 1.5 The results of these tests can be expressed as mass % carbon, hydrogen, or nitrogen. 1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 This 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.

75.080, 75.100