1.1 本试验方法包括通过气相色谱法测定在用发动机机油的燃油稀释度。 1.2 该试验方法可直接进行分析，无需对样品进行预处理或稀释。 1.3 如果样品量在气相色谱仪检测器的线性范围内，则稀释范围的确定没有限制。然而，样品稀释可能会增加结果的潜在误差，并可能影响与第节中给出的值相比获得的精度 14 ，无需稀释即可获得。 1.4 本试验方法的定量范围为10 % （m/m）适用于柴油和生物柴油，最高可达5 % （m/m）表示汽油。 1.5 以国际单位制表示的数值应视为标准值。如果提供了非国际单位制，则用括号表示。 1.6 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 5.1 在典型操作条件下，在用发动机机油的某些燃油稀释是正常的。然而，燃油过度稀释可能导致性能下降、过早磨损或发动机突然故障。该试验方法提供了一种量化燃料稀释水平的方法，允许用户采取必要的措施。 由于与曲轴箱中燃油的老化和降解相关的限制，本试验方法不旨在准确量化在用润滑剂样品中存在的特定燃油。相反，柴油的量化使用模拟老化燃料进行归一化。

1.1 This test method covers the determination of fuel dilution for in-service engine oil by gas chromatography. 1.2 Analysis can be performed directly by this test method without pretreatment or dilution of the sample. 1.3 There is no limitation for the determination of the dilution range, provided the amount of sample is within the linear range of the gas chromatograph detector. However, sample dilution can add potential error to the result and may affect the precision obtained as compared to the values presented in Section 14 , which were obtained with no dilution. 1.4 This test method covers a quantitation range up to 10 % (m/m) for diesel and biodiesel, and up to 5 % (m/m) for gasoline. 1.5 The values stated in SI units are to be regarded as standard. Where non-SI units are provided, they are shown in parentheses. 1.6 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. ====== Significance And Use ====== 5.1 Some fuel dilution of in-service engine oil is normal under typical operating conditions. However, excessive fuel dilution can lead to decreased performance, premature wear, or sudden engine failure. This test method provides a means of quantifying the level of fuel dilution, allowing the user to take necessary action. This test method does not purport to accurately quantify the specific fuel present in the in-service lubricant samples due to limitations associated with the aging and degradation of the fuel in the crankcase. Rather, quantification of diesel fuel is normalized using a simulated aged fuel.