1.1 这些试验方法包括测定水中的六价铬和总铬。部分 34 质量控制与这些试验方法有关。包括以下三种试验方法: 试验方法 浓度 范围 小节 A-光度二苯基- 碳酰肼 0.01至0.5毫克/升 7 – 15 B-原子吸收， 直接的 0.1至10毫克/升 16 – 24 C-原子吸收，石墨 熔炉 5至100微克/升 25 – 33 1.2 试验方法A是一种仅测量溶解六价铬的光度法。六价铬也可通过离子色谱法测定，见试验方法 D5257 . 试验方法B和C是原子吸收法，通常适用于在不考虑价态的情况下测定水中溶解或总可回收铬。ICP-MS或ICP-AES也可能适用，但仪器成本较高。见测试方法 D5673 和 D1976 . 1.3 试验方法A已成功用于试剂级水类型I、II和III，自来水，10 % 氯化钠溶液、来自符合国家污染物排放消除系统（NPDES）许可证要求的合成有机工业厂的处理水，以及EPA提取程序渗滤液水、工艺用水、湖水、废水处理，即石灰中和和沉淀废酸洗液以及不锈钢酸洗的相关冲洗水。试验方法C已成功用于试剂水、原料洗涤器水、湖水、过滤自来水、河水、井水、生产装置水和中等BTU煤气化过程中的冷凝水。除试剂水外，所用基质不适用于测试方法B。用户有责任确保这些测试方法对未测试基质水的有效性。 1.4 以国际单位制表示的数值应视为标准值。括号中给出的值是英寸-磅单位的数学转换，仅供参考，不被视为标准值。 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。 有关具体的危险说明，请参阅 4.2 , 20.3 和 20.8.1 . 1.6 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====== 4.1 六价铬盐广泛用于金属表面处理和电镀应用、铝阳极氧化以及涂料、染料、炸药和陶瓷的制造。三价铬盐在纺织染色、陶瓷和玻璃工业、皮革工业和摄影中用作媒染剂。铬可能存在于这些行业的废水中，也可能从铬酸盐处理的冷却水中排放。 4.2 铬的六价态对人类、动物和水生生物有毒。吸入后可产生肺部肿瘤，并容易引起皮肤过敏。

1.1 These test methods cover the determination of hexavalent and total chromium in water. Section 34 on Quality Control pertains to these test methods. Three test methods are included as follows: Test Method Concentration Range Sections A—Photometric Diphenyl- carbohydrazide 0.01 to 0.5 mg/L 7 – 15 B—Atomic Absorption, Direct 0.1 to 10 mg/L 16 – 24 C—Atomic Absorption, Graphite Furnace 5 to 100 μg/L 25 – 33 1.2 Test Method A is a photometric method that measures dissolved hexavalent chromium only. Hexavalent chromium can also be determined by ion chromatography, see Test Method D5257 . Test Methods B and C are atomic absorption methods that are generally applicable to the determination of dissolved or total recoverable chromium in water without regard to valence state. ICP-MS or ICP-AES may also be appropriate but at a higher instrument cost. See Test Methods D5673 and D1976 . 1.3 Test Method A has been used successfully with reagent grade water Types I, II, and III, tap water, 10 % NaCl solution, treated water from a synthetic organic industrial plant that meets National Pollution Discharge Elimination System (NPDES) permit requirements, and EPA-extraction procedure leachate water, process water, lake water, effluent treatment, that is, lime neutralization and precipitation of spent pickle liquor and associated rinse water from stainless steel pickling. Test Method C has been used successfully with reagent water, stock scrubber water, lake water, filtered tap water, river water, well water, production plant water, and a condensate from a medium BTU coal gasification process. Matrices used, except for reagent water, are not available for Test Method B. It is the user's responsibility to ensure the validity of these test methods for waters of untested matrices. 1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversion to inch-pound units that are provided for information only and are not considered 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see 4.2 , 20.3 , and 20.8.1 . 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 ====== 4.1 Hexavalent chromium salts are used extensively in metal finishing and plating applications, in anodizing aluminum, and in the manufacture of paints, dyes, explosives, and ceramics. Trivalent chromium salts are used as mordants in textile dyeing, in the ceramic and glass industry, in the leather industry as a tanning agent, and in photography. Chromium may be present in wastewater from these industries and may also be discharged from chromate-treated cooling waters. 4.2 The hexavalent state of chromium is toxic to humans, animals, and aquatic life. It can produce lung tumors when inhaled and readily induces skin sensitization.