1.1 本试验方法使用特定的自动颗粒计数器 2. （APC）计算和测量轻馏分和中间馏分燃料以及生物燃料（如生物柴油和生物柴油混合物）中分散的污垢颗粒、水滴和其他颗粒的大小，总范围为4 µm（c）至100 µm（c）和尺寸范围内 ≥ 4. µm（c）， ≥ 6. µm（c），和 ≥ 14 µm（c）。 注1: 本试验方法范围内的ASTM和军用规范燃料包括以下规范: D975 1D和2D级， D1655 , D3699 , D4814 （参见 14.1.1.1 ), D6751 , D7467 ，馏出物等级 D396页 和 D2880 ，MIL-DTL-83133和MIL-DTL-16884。 注2: 在本试验方法中，将水滴计为颗粒，将凝聚颗粒检测并计为单个较大颗粒。污垢包括生物颗粒。尽管测量了颗粒的投影面积，但在本试验方法中，其表示为球体的直径。 注3: 与粒度一起使用的符号（c）用于表示仪器已根据ISO 11171进行校准。严格来说，这只适用于50以下的粒子 µm。 注4: 本试验方法可用于粒径不超过100的颗粒 µm（c），但精度仅针对尺寸带确定 ≥ 4. µm（c）， ≥ 6. µm（c），和 ≥ 14 µm（c）。所有测量值均为每毫升。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.3 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、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法旨在实验室或现场使用，以评估馏出燃料和液体生物燃料的清洁度。它不适用于在线应用程序。 5.2 该测试方法优于传统的过滤方法，因为它是一种精确快速的测试，并且优于视觉方法，因为它不是主观的。 5.3 颗粒数的增加可能表明燃料状况的变化，例如由储存或转移引起的变化。 5.4 高浓度的颗粒会导致过滤器堵塞，并严重影响泵、喷油器、活塞和其他运动部件的寿命。 与冶金有关的粒度知识可以提供重要信息，特别是如果从其他来源也知道颗粒的硬度。 5.5 本试验方法规定了报告粒度带测量值的最低要求（见 A1.1.2 ). 某些特定应用可能需要在其他粒度范围内进行测量。 5.6 获得代表性样品并遵循推荐的样品和试样制备程序和时间尺度对于颗粒计数方法尤为重要。（参见章节 8. , 10 , 14.1.4 和 附注8 .) 5.7 该试验方法也可用于通过对燃料进行化学预处理来估计航空涡轮燃料中不包括自由水滴的总颗粒数。看见 附录X2 .

1.1 This test method uses a specific automatic particle counter 2 (APC) to count and measure the size of dispersed dirt particles, water droplets and other particles, in light and middle distillate fuel, and bio fuels such as biodiesel and biodiesel blends, in the overall range from 4 µm(c) to 100 µm(c) and in the size bands ≥ 4 µm(c), ≥ 6 µm(c), and ≥ 14 µm(c). Note 1: ASTM and military specification fuels falling within the scope of this test method include Specifications: D975 grades 1D and 2D, D1655 , D3699 , D4814 (see 14.1.1.1 ), D6751 , D7467 , distillate grades of D396 and D2880 , MIL-DTL-83133, and MIL-DTL-16884. Note 2: For the purposes of this test method, water droplets are counted as particles, and agglomerated particles are detected and counted as a single larger particle. Dirt includes biological particles. Although the projected area of a particle is measured, this is expressed as the diameter of a sphere for the purposes of this test method. Note 3: The notation (c), used with particle sizes, is used to denote that the apparatus has been calibrated in accordance with ISO 11171. Strictly this only applies to particles up to 50 µm. Note 4: This test method may be used for particle sizes bands up to 100 µm(c), however the precision has only been determined for the size bands ≥ 4 µm(c), ≥ 6 µm(c), and ≥ 14 µm(c). All measurements are per millilitre. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 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 This test method is intended for use in the laboratory or in the field for evaluating the cleanliness of distillate fuels, and liquid bio fuels. It is not applicable to on or in-line applications. 5.2 This test method offers advantage over traditional filtration methods in that it is a precise rapid test, and advantage over visual methods as it is not subjective. 5.3 An increase in particle counts can indicate a change in the fuel condition caused by storage or transfer for example. 5.4 High levels of particles can cause filter blockages and have a serious impact on the life of pumps, injectors, pistons and other moving parts. Knowledge of particle size in relation to the metallurgy can provide vital information especially if the hardness of particles is also known from other sources. 5.5 This test method specifies a minimum requirement for reporting measurements in particle size bands (see A1.1.2 ). Some specific applications may require measurements in other particle size bands. 5.6 Obtaining a representative sample and following the recommended sample and test specimen preparation procedures and timescales is particularly important with particle counting methods. (See Sections 8 , 10 , 14.1.4 and Note 8 .) 5.7 This test method can also be used to estimate the total particulate counts excluding free water droplets in aviation turbine fuels by a chemical pretreatment of the fuel. See Appendix X2 .