1.1本试验方法涵盖了环境大气中六价铬[Cr（VI）]的收集和测量。 1.2本试验方法使用湿式冲击取样技术中的碱性冲击器缓冲溶液收集并稳定大气中的六价铬。铬酸铅 4. ]通常认为其在水中可溶性较差，在撞击式除尘器溶液中可溶性高达940μg/L，为六价铬。 1.3本试验方法使用离子色谱分离、与比色试剂的分离后反应和光度检测来测量六价铬。 1.4本试验方法适用于0.2至100纳克/米的范围 3. 假设20 m，大气中六价铬的浓度 3. 空气样本。可通过适当稀释将范围向上扩展。 1.5以国际单位制表示的数值应视为标准。括号中的英寸-磅单位仅供参考。 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====== 5.1流行病学研究表明，当人类暴露于相对较高的空气中浓度时，六价铬是一种人体呼吸道致癌物。这种高暴露也可能导致人体皮肤对六价铬过敏 (5) . 5.2六价铬的环境大气浓度远低于取样方法的检测限，包括试验方法D3586和NIOSH-7600 (2) . 5.3六价铬环境大气浓度的客观评估提供了一种以与健康相关的方式评估大气六价铬暴露的方法- 基于风险水平。收集此类实际监测数据减少或消除了理论再悬浮建模的需要，并为潜在暴露的健康评估提供了改进的基础 (5) . 5.4缓冲撞击式取样技术提供了取样介质的pH控制，可在取样过程中稳定六价铬的氧化状态 (6) . 5.5离子色谱法提供了一种将六价铬与样品中存在的其他物种分离的方法，其中许多物种干扰了其他检测方法。这种分离与灵敏的比色检测方法相结合，为六价铬提供了一种选择性和灵敏的分析方法，只需最少的样品制备 (1) .

1.1 This test method covers the collection and measurement of hexavalent chromium [Cr(VI)] in the ambient atmosphere. 1.2 This test method collects and stabilizes atmospheric hexavalent chromium using an alkaline impinger buffer solution in a wet impingement sampling technique. Lead chromate [PbCrO 4 ], generally considered poorly soluble in water, is soluble in the impinger solution up to 940 μg/L as hexavalent chromium. 1.3 This test method measures hexavalent chromium using an ion chromatographic separation combined with a post separation reaction with a colorimetric reagent and photometric detection. 1.4 This test method is applicable in the range from 0.2 to 100 ng/m 3 of hexavalent chromium in the atmosphere assuming 20 m 3 of air sample. The range can be extended upwards by appropriate dilution. 1.5 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only. 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 ====== 5.1 Hexavalent chromium has been shown to be a human respiratory carcinogen in epidemiological studies when humans are exposed to relatively high airborne concentrations. Such high exposures may also induce dermal sensitization to hexavalent chromium in humans (5) . 5.2 Ambient atmospheric concentrations of hexavalent chromium are well below detection limits of sampling methods including Test Method D3586 and NIOSH-7600 (2) . 5.3 Objective assessment of ambient atmospheric concentrations of hexavalent chromium provides a means of evaluating exposures to atmospheric hexavalent chromium in a manner that can be related to health-based risk levels. Collecting such actual monitoring data reduces or eliminates the need for theoretical resuspension modeling and provides improved basis for health assessments of potential exposures (5) . 5.4 The buffered impinger sampling technique provides pH control of the sampling medium, which stabilizes the oxidation state of hexavalent chromium during sampling (6) . 5.5 Ion chromatography provides a means of separating the hexavalent chromium from other species present in the sample, many of which interfere with other detection methods. The combination of this separation with a sensitive colorimetric detection method provides a selective and sensitive analytical method for hexavalent chromium with minimal sample preparation (1) .