1.1 本规程提供了分析前验证水样pH值的信息。本规程不适用于油或油脂等非水性样品。 1.2 本规程也可用于在各种分析步骤中调整样品的pH值。 1.3 宽范围pH值纸/条用于快速指示pH值至约1 pH单位，窄范围pH值纸/条用于指示pH值至约0.5 pH单位。 1.4 在某些情况下，可以使用通用液体指示器。 1.5 单位- 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 本实践提供了一组用于执行一个或多个特定操作的说明。 本文件不能取代教育或经验，应与专业判断一起使用。并非本惯例的所有方面都适用于所有情况。本ASTM国际标准不代表或取代必须根据其判断给定专业服务的充分性的谨慎标准，也不应在不考虑项目的许多独特方面的情况下应用本文件。标题中的“标准”一词仅表示该文件已通过ASTM共识程序获得批准。 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 本规程旨在供采样器、技术人员或分析员使用，以验证样品是否保存或在分析程序中规定的适当pH值下。 5.2 宽范围纸张的pH值在约1个pH单位内，窄范围纸张的pH值在0.5个pH单位内。 5.3 除非试验方法中另有规定，否则- 在1个单位内估算pH值是合适的。 5.4 pH值范围较窄的纸条可用于pH值要求较高的试验方法；然而，不应暗示精度优于估计的±0.5 pH单位。 5.5 快速pH测试允许用户在没有辅助设备的情况下直接进行斑点测定。

1.1 This practice provides information on verifying the pH of aqueous samples before analysis. This practice is not intended to be used for non-aqueous samples like oil or grease. 1.2 This practice may also be used in adjusting pH of samples during various analytical steps. 1.3 Wide-range pH papers/strips are used for a rapid indication of pH to within about 1 pH unit, and narrow-range pH papers/strips are used to indicate pH within about 0.5 pH units. 1.4 In some instances, a universal liquid indicator may be used. 1.5 Units— The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM International standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title means only that the document has been approved through the ASTM consensus process. 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 This practice is intended for use by samplers, technicians, or analysts to verify that samples are preserved or at the proper pH specified in analytical procedures. 5.2 The pH is indicated within about 1 pH unit for wide-range paper and within 0.5 pH units for narrow-range paper. 5.3 Unless stated otherwise in the test method, a wide-range paper estimating pH within 1 unit is suitable. 5.4 A narrow-range pH paperstrip may be used for test methods with tighter pH requirements; however, accuracy better than ±0.5 pH units of the estimate should not be implied. 5.5 Rapid pH tests allow users to make spot determinations directly without auxiliary equipment.