1.1 该测试方法是使用透射电子显微镜（TEM）测定环境大气中碳纳米管和含碳纳米管颗粒浓度的分析程序。 1.1.1 该试验方法适用于环境（室外）和建筑大气中碳纳米管的测定。 1.2 该试验方法适用于吸入已知体积空气的聚碳酸酯毛细管孔过滤器和空白过滤器。 1.3 如果分析的样品收集过滤器的一般颗粒物负载超过约25，则不能使用直接分析方法 % 颗粒物对收集过滤器的覆盖。 1.4 单位-- 以国际单位制表示的数值应视为标准。本标准中不包括其他计量单位。 1.5 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。 1.6 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 该测试方法适用于在各种环境空气情况下测量空气中的碳纳米管，并用于评估碳纳米管结构的任何大气。环境大气中的单个碳纳米管结构的直径低于光学显微镜的分辨率极限。该测试方法基于透射电子显微镜，其具有足够的分辨率，可以检测小而薄的单个碳纳米管，并且目前是一种可靠的技术，能够明确识别大多数纳米管结构。 碳纳米管通常不是单一的碳纳米管，而是非常复杂的聚集结构，可以与其他颗粒聚集，也可以不与其他颗粒聚合。 5.2 该测试方法适用于单个滤波器的分析，并描述了单个滤波器测量的精度。通常需要多个空气样本来表征空气中纳米管结构在时间和空间上的浓度。为此目的所需的样本数量与样本之间的测量变化成比例，该变化可能大于单个样本的测量变化。

1.1 This test method is an analytical procedure using transmission electron microscopy (TEM) for the determination of the concentration of carbon nanotubes and carbon nanotube-containing particles in ambient atmospheres. 1.1.1 This test method is suitable for determination of carbon nanotubes in both ambient (outdoor) and building atmospheres. 1.2 This test method is defined for polycarbonate capillary pore filters through which a known volume of air has been drawn and for blank filters. 1.3 The direct analytical method cannot be used if the general particulate matter loading of the sample collection filter as analyzed exceeds approximately 25 % coverage of the collection filter by particulate matter. 1.4 Units— The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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. 1.6 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 applicable to the measurement of airborne carbon nanotubes in a wide range of ambient air situations and for evaluation of any atmosphere for carbon nanotube structures. Single carbon nanotube structures in ambient atmospheres have diameters below the resolution limit of the light microscope. This test method is based on transmission electron microscopy, which has adequate resolution to allow detection of small thin single carbon nanotubes and is currently a reliable technique capable of unequivocal identification of the majority of nanotube structures. Carbon nanotubes are often found, not as single carbon nanotubes, but as very complex, aggregated structures, which may or may not be aggregated with other particles. 5.2 This test method applies to the analysis of a single filter and describes the precision attributable to measurements for a single filter. Multiple air samples are usually necessary to characterize airborne nanotube structure concentrations across time and space. The number of samples necessary for this purpose is proportional to the variation in measurement across samples, which may be greater than the variation in measurement for a single sample.