1.1 本试验方法包括吸入毒理学研究中吸入暴露室内空气中金属氧化物纳米颗粒表面积的测定。表面积可通过使用吸附物如氮、氪和氩的气体吸附方法测量（Brunauer等人。 ( 1. ) , 2. 安德森 ( 2. ) 、Gregg和Sing ( 3. ) )或通过基于离子附着和迁移率的方法（Ku和Maynard ( 4. ) ). 本试验方法适用于通过氪气吸附气体吸附测量表面积。 该测试方法允许使用任何现代商用氪吸附仪器，但严格规定了金属和金属氧化物纳米颗粒的样品收集、脱气和分析程序。由于颗粒负载样品的总表面积较低，并且需要准确测量用于样品收集的过滤器的背景表面积，因此需要使用氪。仪器报告了基于多点Brunauer、Emmett和Teller（BET）方程的表面积值（Brunaueret al。 ( 1. ) ，安德森 ( 2. ) 、Gregg和Sing ( 3. ) )用于计算过滤器上收集的空气中纳米颗粒的表面积。 1.2 以国际单位制表示的值应视为标准值。本标准不包括其他测量单位。以国际单位制表示所有数值，除非特定仪器软件使用替代单位报告表面积。 1.3 本标准并不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建立适当的安全、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《国际标准、指南和建议制定原则决定》中确立的国际公认标准化原则制定的。 =====意义和用途====== 5.1 为了对吸入毒理学实验中观察到的剂量-反应关系得出有意义的结论，有必要对纳米颗粒特性进行分级表征。 这种分层策略包括纳米颗粒的表征 生产时 （即，以供应商出售的散装材料计量）和 按管理 （即，在向受试者递送时测量）（Oberdorster等人。 ( 6. ) ). 5.2 试验方法 B922型 和 第1274页 以及ISO 9277和ISO 18757用于测定 生产时 大块金属和金属氧化物粉末的表面积。在吸入暴露室中输送纳米颗粒的过程中，材料特性可能发生变化，因此具有不同于材料的特性 生产时 本试验方法描述了 按管理 用于吸入毒理学研究的吸入暴露室内空气中金属氧化物纳米颗粒的表面积。

1.1 This test method covers determination of surface area of airborne metal oxide nanoparticles in inhalation exposure chambers for inhalation toxicology studies. Surface area may be measured by gas adsorption methods using adsorbates such as nitrogen, krypton, and argon (Brunauer et al. ( 1 ) , 2 Anderson ( 2 ) , Gregg and Sing ( 3 ) ) or by ion attachment and mobility-based methods (Ku and Maynard ( 4 ) ). This test method is specific to the measurement of surface area by gas adsorption by krypton gas adsorption. The test method permits the use of any modern commercial krypton adsorption instruments but strictly defines the sample collection, outgassing, and analysis procedures for metal and metal oxide nanoparticles. Use of krypton is required due to the low overall surface area of particle-laden samples and the need to accurately measure the background surface area of the filter used for sample collection. Instrument-reported values of surface area based on the multipoint Brunauer, Emmett and Teller (BET) equation (Brunauer et al. ( 1 ) , Anderson ( 2 ) , Gregg and Sing ( 3 ) ) are used to calculate surface area of airborne nanoparticles collected on a filter. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. State all numerical values in terms of SI units unless specific instrumentation software reports surface area using alternate units. 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 A tiered strategy for characterization of nanoparticle properties is necessary to draw meaningful conclusions concerning dose-response relationships observed during inhalation toxicology experiments. This tiered strategy includes characterization of nanoparticles as produced (that is, measured as the bulk material sold by the supplier) and as administered (that is, measured at the point of delivery to a test subject) (Oberdorster et al. ( 6 ) ). 5.2 Test Methods B922 and C1274 and ISO 9277 and ISO 18757 exist for determination of the as produced surface area of bulk metal and metal oxide powders. During the delivery of nanoparticles in inhalation exposure chambers, the material properties may undergo change and therefore have properties that differ from the material as produced . This test method describes the determination of the as administered surface area of airborne metal oxide nanoparticles in inhalation exposure chambers for inhalation toxicology studies.