1.1本试验方法涵盖以下程序:( 一 )确定灰尘中的石棉和( b )提供采样粉尘中石棉表面负荷的估计值，报告为每单位面积采样表面的石棉质量或每质量采样粉尘的石棉质量。 1.1.1如果要确定石棉结构数量的估计值，请用户参考试验方法D 5755 . 1.2本试验方法描述了通过微真空技术对石棉水平的非空气粉尘进行采样所需的设备和程序。非气载样品在标准滤膜盒内收集，从可能含有石棉的粉尘表面区域取样。 1.2.1本程序使用了显微取样技术。这种技术的收集效率未知。任何特定基质和不同类型基质的收集效率的可变性也未知。 采样效率差异和可变性对粉尘采样测量解释的影响尚未确定。 1.3通过透射电子显微镜（TEM）鉴定的石棉基于形态学、选区电子衍射（SAED）和能量色散X射线分析（EDXA）。还确定了有关结构尺寸的一些信息。 1.4本试验方法通常适用于从每平方厘米约0.24 pg石棉开始估算石棉的表面载荷（假设最小纤维尺寸为0.5 pg） μ m乘以0.025 μ m、 见17.8），但将随17.8中所述的分析参数而变化。 1.4.1本试验方法中概述的程序采用间接样品制备技术。其目的是将石棉分解并分散成纤维和纤维束，通过透射电子显微镜可以更准确地识别、计数和确定尺寸。 然而，与所有间接样品制备技术一样，为定量而观察到的石棉可能并不代表采样时石棉的物理形态。更具体地说，所述程序既不会产生也不会破坏石棉，但可能会改变矿物纤维的物理形态。 1.5以国际单位制表示的数值应视为标准。 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====== 这种微量采样和间接分析方法用于石棉非空气粉尘样品的一般测试。它用于帮助评估建筑物表面可能存在的灰尘，如天花板、货架、电气部件、管道工程、地毯等。 本试验方法提供了根据定量TEM分析得出的每单位面积的石棉质量或每质量采样粉尘的石棉质量报告的粉尘中石棉质量表面负载的估计值。 本试验方法未描述评估含石棉材料建筑物的安全性或可居住性，或是否符合联邦、州或地方法规或法令所需的程序或技术。用户有责任做出这些决定。 目前，通过本试验方法测量的含石棉粉尘与人类暴露于空气中石棉的潜在风险之间尚未建立任何关系。因此，用户在解释从本试验方法获得的数据时应考虑其他可用信息。 灰尘的定义接受所有小到足以通过1毫米筛网的颗粒。因此，单个大石棉- 在样品制备过程中分解的含有颗粒（来自粒径分布的大端）可能会导致该样品的TEM分析中产生异常大的石棉表面负载。相反，未能分解大颗粒可能导致石棉质量表面负荷异常低。因此，建议从同一区域获得多个独立样本，并在整个程序中至少分析三个样本。

1.1 This test method covers a procedure to ( a ) identify asbestos in dust and ( b ) provide an estimate of the surface loading of asbestos in the sampled dust, reported as either the mass of asbestos per unit area of sampled surface or as the mass of asbestos per mass of sampled dust. 1.1.1 If an estimate of asbestos structure counts is to be determined, the user is referred to Test Method D 5755 . 1.2 This test method describes the equipment and procedures necessary for sampling, by a microvacuum technique, non-airborne dust for levels of asbestos. The non-airborne sample is collected inside a standard filter membrane cassette from the sampling of a surface area for dust which may contain asbestos. 1.2.1 This procedure uses a microvacuuming sampling technique. The collection efficiency of this technique is unknown. Variability of collection efficiency for any particular substrate and across different types of substrates is also unknown. The effects of sampling efficiency differences and variability on the interpretation of dust sampling measurements have not been determined. 1.3 Asbestos identified by transmission electron microscopy (TEM) is based on morphology, selected area electron diffraction (SAED), and energy dispersive X-ray analysis (EDXA). Some information about structure size is also determined. 1.4 This test method is generally applicable for an estimate of the surface loading of asbestos starting from approximately 0.24 pg of asbestos per square centimetre (assuming a minimum fiber dimension of 0.5 μ m by 0.025 μ m, see 17.8), but will vary with the analytical parameters noted in 17.8. 1.4.1 The procedure outlined in this test method employs an indirect sample preparation technique. It is intended to disaggregate and disperse asbestos into fibrils and fiber bundles that can be more accurately identified, counted, and sized by transmission electron microscopy. However, as with all indirect sample preparation techniques, the asbestos observed for quantitation may not represent the physical form of the asbestos as sampled. More specifically, the procedure described neither creates not destroys asbestos, but it may alter the physical form of the mineral fibers. 1.5 The values stated in SI units are to be regarded as the standard. 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 ====== This microvacuum sampling and indirect analysis method is used for the general testing of non-airborne dust samples for asbestos. It is used to assist in the evaluation of dust that may be found on surfaces in buildings, such as ceiling tiles, shelving, electrical components, duct work, carpet, etc. This test method provides an estimate of the mass surface loading of asbestos in the dust reported as either the mass of asbestos per unit area or as the mass of asbestos per mass of sampled dust as derived from a quantitative TEM analysis. This test method does not describe procedures or techniques required to evaluate the safety or habitability of buildings with asbestos-containing materials, or compliance with federal, state, or local regulations or statutes. It is the user's responsibility to make these determinations. At present, no relationship has been established between asbestos-containing dust as measured by this test method and potential human exposure to airborne asbestos. Accordingly, the users should consider other available information in their interpretation of the data obtained from this test method. This definition of dust accepts all particles small enough to pass through a 1 mm screen. Thus, a single, large asbestos-containing particle(s) (from the large end of the particle size distribution) disassembled during sample preparation may result in anomalously large asbestos surface loading results in the TEM analyses of that sample. Conversely, failure to disaggregate large particles may result in anomalously low asbestos mass surface loadings. It is, therefore, recommended that multiple independent samples be secured from the same area, and that a minimum of three samples be analyzed by the entire procedure.