1.1 本试验方法包括使用标准单缸、四冲程循环、可变压缩比、间接喷射柴油发动机，根据十六烷值的任意比例确定柴油的额定值。 1.2 十六烷值范围从零（0）到100，但典型的测试范围是30到65十六烷值。 1.3 操作条件的值以国际单位制表示，并被视为标准。括号中给出的数值为历史英寸磅单位，仅供参考。此外，由于为这些单位创建了大量且昂贵的工具，发动机测量值仍以英寸磅为单位。 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 有关更具体的警告语句，请参阅 附件A1 . 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 十六烷值提供了压燃式发动机中柴油燃料油点火特性的度量。 5.2 该测试方法被发动机制造商、炼油商和营销人员使用，并在商业中作为与燃料和发动机匹配相关的主要规格测量。 5.3 十六烷值是在预燃室式压燃试验发动机中以恒定速度确定的。测试发动机性能与全尺寸、变速、可变负载发动机的关系尚不完全清楚。 5.4 该试验方法可用于非常规燃料，如合成燃料、植物油等。然而，这种材料在全尺寸发动机中与性能的关系尚不完全清楚。

1.1 This test method covers the determination of the rating of diesel fuel oil in terms of an arbitrary scale of cetane numbers using a standard single cylinder, four-stroke cycle, variable compression ratio, indirect injected diesel engine. 1.2 The cetane number scale covers the range from zero (0) to 100, but typical testing is in the range of 30 to 65 cetane number. 1.3 The values for operating conditions are stated in SI units and are to be regarded as the standard. The values given in parentheses are the historical inch-pound units for information only. In addition, the engine measurements continue to be in inch-pound units because of the extensive and expensive tooling that has been created for these units. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For more specific warning statements, see Annex A1 . 1.5 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. ====== Significance And Use ====== 5.1 The cetane number provides a measure of the ignition characteristics of diesel fuel oil in compression ignition engines. 5.2 This test method is used by engine manufacturers, petroleum refiners and marketers, and in commerce as a primary specification measurement related to matching of fuels and engines. 5.3 Cetane number is determined at constant speed in a precombustion chamber type compression ignition test engine. The relationship of test engine performance to full scale, variable speed, variable load engines is not completely understood. 5.4 This test method may be used for unconventional fuels such as synthetics, vegetable oils, and the like. However, the relationship to the performance of such materials in full scale engines is not completely understood.