1.1 本规程涵盖了按数量测定粒径范围约为0.01至5.0μm的颗粒物在粉尘控制区和洁净室中的颗粒物浓度和粒径分布。颗粒物浓度不超过3.5 × 10 6. 颗粒/米 3. (100 000/英尺 3. )覆盖所有等于或大于最小测量尺寸的颗粒。 1.2 本规程使用机载单粒子计数装置（SPC），其操作基于测量通过传感区的单个粒子产生的信号。信号必须与颗粒大小直接或间接相关。 注1: 此处未指定SPC类型。SPC可以是常规光学粒子计数器（OPC）、空气动力粒度仪、冷凝核计数器（CNC），与扩散电池或差分迁移率分析仪一起工作，或任何其他能够在关注的粒径范围内计算和确定单个粒子大小以及在洁净室环境中采样的设备。 1.3 根据本规程进行测试的人员应接受SPC使用培训，并应了解其操作。 1.4 由于空气中颗粒物的浓度和粒度分布会不断变化，因此采样探头配置、位置和采样时间的选择将影响采样结果。此外，各种SPC之间的物理测量、电子和样品处理系统的差异以及被测量的各种粒子的物理特性的差异可能会导致测试结果的变化。应通过使用标准的主要校准方法和最小化样本采集程序的可变性来识别和最小化这些差异。 1.5 根据不同的洁净室等级，可以为特定应用选择样本采集程序和设备。 这些选择的明确要求超出了本惯例的范围；然而，应说明采样实践，以考虑洁净室中悬浮颗粒的潜在空间和统计变化。 注2: 洁净室分类的一般参考遵循联邦标准 209E，最新版。如果要在不符合这些分类的粉尘控制区域内对气载颗粒物进行表征，则应使用这些区域相关规范的最新版本。 1.6 单位- 以国际单位制表示的数值应视为标准值。国际单位制后括号中给出的值仅供参考，不被视为标准值。 1.7 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。 有关具体的危险声明，请参阅第节 8. . 1.8 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 本规程的主要目的是描述一种程序，用于收集由单颗粒计数技术指示的洁净区域内空气颗粒浓度和粒径分布的近实时数据。一些政府和行业规范的实施需要使用SPC获取粒度和浓度数据。 5.2 在洁净室制造的许多产品的加工要求涉及的环境清洁度水平非常低，因此需要一个能够检测微小颗粒的单颗粒计数器来表征洁净室空气的特性。 只有使用SPC才能获得尺寸范围从0.1μm到5μm及以上的空气颗粒浓度的实时信息。可以通过直接测量单个颗粒的光散射来定义大于约0.05μm的颗粒；对于较小的颗粒，可能需要其他技术，例如在颗粒测量之前通过冷凝进行初步生长。 5.3 粒径数据参考用于校准SPC的粒子系统。不同SPC之间的检测、电子和样品处理系统的差异可能导致粒子特性的差异。在尝试比较来自与校准基材成分或形状显著不同的颗粒的数据时，必须小心。使用具有不同操作参数的类似粒子传感系统的仪器之间也可能发生变化。 应通过使用SPC校准和操作的标准方法来识别和最小化这些影响。 5.4 在应用这一实践中，基本假设是通过SPC的样品中的颗粒代表了被分析的整个粉尘控制区域中的颗粒。需要注意使用良好的采样程序，并且在样本处理和分析过程中的任何时候都不会产生伪影；这些预防措施在SPC的验证和操作中都是必要的。

1.1 This practice covers the determination of the particle concentration, by number, and the size distribution of airborne particles in dust-controlled areas and clean rooms, for particles in the size range of approximately 0.01 to 5.0 μm. Particle concentrations not exceeding 3.5 × 10 6 particles/m 3 (100 000/ft 3 ) are covered for all particles equal to and larger than the minimum size measured. 1.2 This practice uses an airborne single particle counting device (SPC) whose operation is based on measuring the signal produced by an individual particle passing through the sensing zone. The signal must be directly or indirectly related to particle size. Note 1: The SPC type is not specified here. The SPC can be a conventional optical particle counter (OPC), an aerodynamic particle sizer, a condensation nucleus counter (CNC) operating in conjunction with a diffusion battery or differential mobility analyzer, or any other device capable of counting and sizing single particles in the size range of concern and of sampling in a cleanroom environment. 1.3 Individuals performing tests in accordance with this practice shall be trained in use of the SPC and shall understand its operation. 1.4 Since the concentration and the particle size distribution of airborne particles are subject to continuous variations, the choice of sampling probe configuration, locations, and sampling times will affect sampling results. Further, the differences in the physical measurement, electronic, and sample handling systems between the various SPCs and the differences in physical properties of the various particles being measured can contribute to variations in the test results. These differences should be recognized and minimized by using a standard method of primary calibration and by minimizing variability of sample acquisition procedures. 1.5 Sample acquisition procedures and equipment may be selected for specific applications based on varying cleanroom class levels. Firm requirements for these selections are beyond the scope of this practice; however, sampling practices shall be stated that take into account potential spatial and statistical variations of suspended particles in clean rooms. Note 2: General references to cleanroom classifications follow Federal Standard 209E, latest revision. Where airborne particles are to be characterized in dust-controlled areas that do not meet these classifications, the latest revision of the pertinent specification for these areas shall be used. 1.6 Units— The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.7 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 specific hazards statements, see Section 8 . 1.8 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 primary purpose of this practice is to describe a procedure for collecting near real-time data on airborne particle concentration and size distribution in clean areas as indicated by single particle counting techniques. Implementation of some government and industry specifications requires acquisition of particle size and concentration data using an SPC. 5.2 The processing requirements of many products manufactured in a clean room involves environmental cleanliness levels so low that a single particle counter with capability for detecting very small particles is required to characterize clean room air. Real-time information on concentration of airborne particles in size ranges from less than 0.1 μm to 5 μm and greater can be obtained only with an SPC. Definition of particles larger than approximately 0.05 μm may be carried out with direct measurement of light scattering from individual particles; other techniques may be required for smaller particles, such as preliminary growth by condensation before particle measurement. 5.3 Particle size data are referenced to the particle system used to calibrate the SPC. Differences in detection, electronic and sample handling systems among the various SPCs may contribute to differences in particle characterization. Care must be exercised in attempting to compare data from particles that vary significantly in composition or shape from the calibration base material. Variations may also occur between instruments using similar particle sensing systems with different operating parameters. These effects should be recognized and minimized by using standard methods for SPC calibration and operation. 5.4 In applying this practice, the fundamental assumption is made that the particles in the sample passing through the SPC are representative of the particles in the entire dust-controlled area being analyzed. Care is required that good sampling procedures are used and that no artifacts are produced at any point in the sample handling and analysis process; these precautions are necessary both in verification and in operation of the SPC.