1.1 本规程提供了对标准进行修订所需的步骤，这些标准规定了用于测量或控制电极电位的饱和甘汞参比电极（SCE）。 1.2 SCE含有汞，因此在禁止使用汞的地方可能无法使用。本规程涵盖了替代参比电极的选择和使用。 1.3 在规定SCE的试验方法中，有必要使用替代参比电极制定新的精度声明。 1.4 本规程不适用于使用SCE的电位pH测定。 （电位pH测量是一种分析方法，其他地方有介绍。） 1.5 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.6 警告- 许多监管机构已将汞指定为一种危险物质，可导致严重的医疗问题。汞或其蒸汽已被证明对健康有害，并对材料具有腐蚀性。处理汞和含汞产品时要小心。有关更多信息，请参阅适用的产品安全数据表（SDS）。 当地或国家法律禁止销售汞或含汞产品，或两者兼有。用户必须确定其所在地销售的合法性。 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。 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 电极电位测量是许多电化学腐蚀测试方法和实践中必不可少的一步。 5.2 由于SCE可靠、准确、使用简单，且易于获得，因此已广泛用于实验室测试。然而，由于该设备含有汞，而且汞最近已被一些政府机构禁止，因此在禁止使用汞的地方可能无法使用。因此，在禁止使用汞的地方，可能不可能使用SCE的测试方法。因此，有必要为这些标准建立替代参比电极。 5.3 KCl饱和银/氯化银参比电极Ag/AgCl（sat-KCl）是实验室测试方法和实践中SCE的满意替代品。该参比电极应提供与SCE相当的性能和准确性。 5.4 有必要为每种试验方法执行实验室间试验程序，其中规定使用Ag/AgCl（sat-KCl）电极代替SCE，以提高使用新参比电极的方法的精度。 注1: 如果测试方法规定可以使用SCE或Ag/AgCl（sat-KCl）参比电极，并且用于提高方法精度的ILS程序包括大量使用每种参比电极的参与者，则无需额外测试。

1.1 This practice provides the steps necessary to prepare revisions to standards that specify the saturated calomel reference electrode (SCE) for measuring or controlling electrode potentials. 1.2 The SCE contains mercury and, as a result, it may not be available in locations where mercury has been banned. This practice covers the selection and use of an alternative reference electrode. 1.3 In test methods where the SCE is specified, it will be necessary to develop a new precision statement using the alternative reference electrode. 1.4 This practice will not apply to electrometric pH determinations where the SCE has been used. (Electrometric pH measurement is an analytical method that is covered elsewhere.) 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 Warning— Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location. 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. 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 Electrode potential measurement is an essential step in many electrochemical corrosion test methods and practices. 5.2 The SCE has been widely specified for laboratory tests because it is reliable, accurate, simple to use, and it has been readily available. However, because this device contains mercury, and mercury has recently been banned by some governmental agencies, it may not be available in locations where mercury is banned. As a result, test methods using the SCE may not be possible in locations where mercury is banned. Therefore, it is necessary to establish an alternative reference electrode for these standards. 5.3 The KCl saturated, silver/silver chloride reference electrode, Ag/AgCl (sat KCl), is a satisfactory replacement for the SCE in laboratory test methods and practices. This reference electrode should provide comparable performance and accuracy to the SCE. 5.4 It will be necessary to carry out interlaboratory test programs for each test method where the Ag/AgCl (sat KCl) electrode is specified to replace the SCE, in order to develop the precision of the method using the new reference electrode. Note 1: In cases where a test method specifies that either the SCE or the Ag/AgCl (sat KCl) reference electrode may be used, and the ILS program used to develop the precision of the method included significant numbers of participants using each of these reference electrodes, no additional testing is required.