1.1 本试验方法包括测量用作生长介质的泥炭材料的pH值。该测量确定悬浮在水中和0.01M氯化钙溶液中的泥炭材料的酸度或碱度。在两种液体中进行测量是必要的，以充分确定泥炭的pH值。该变量有助于评估泥炭植物环境的可行性。本试验方法不适用于纸张或建筑材料中的泥炭。试验方法 D4972 用于土壤pH测试和测试方法 G51型 用于腐蚀分析土壤的pH测试（参见 注1 ). 注1: 应各小组委员会的要求，有意将这三项标准分开，以便于澄清。 1.2 单位- 以SI单位给出的值应视为标准。 本标准不包括其他计量单位。 1.3 所有测量值和计算值应符合实践中制定的有效数字和四舍五入准则 D6026 . 1.3.1 本标准中用于规定如何收集/记录和计算数据的程序被视为行业标准。此外，它们代表了通常应保留的有效数字。所使用的程序不考虑材料变化、获取数据的目的、特殊目的研究或用户目标的任何考虑；并且通常的做法是增加或减少报告数据的有效数字以与这些考虑相称。考虑工程设计分析方法中使用的有效数字超出了本标准的范围。 1.4 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《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 泥炭的pH值是确定矿物溶解度、泥炭中离子迁移率以及评估泥炭生存能力的有用变量- 植物环境。在测试水和氯化钙溶液中进行pH测量，因为测试水中的pH读数可以被盐（如肥料材料）改变，而氯化钙溶液的观察pH实际上与泥炭中存在的盐的初始量无关。由于通过阳离子交换释放更多的氢离子，氯化钙溶液中获得的pH值通常比测试水中的测量值低约0.5至0.8个pH单位。这两种测量都需要完全确定泥炭的pH值特征。 5.2 pH测量用于农业、环境、岩土和自然资源领域。当评估泥炭作为表土或植物生长介质时，泥炭材料的pH值很有帮助。 注2: 本标准产生的结果质量取决于执行人员的能力以及所用设备和设施的适用性。 符合实践标准的机构 D3740 通常认为能够胜任和客观的测试/取样/检查等。本标准的使用者应注意遵守实践 D3740 其本身不能保证可靠的结果。可靠的结果取决于许多因素；实践 D3740 提供了评估其中一些因素的方法。

1.1 This test method covers the measurement of the pH of peat materials used as a growing medium. This measurement determines the degree of acidity or alkalinity in peat materials suspended in water and a 0.01 M calcium chloride solution. Measurements in both liquids are necessary to fully define the peat’s pH. This variable is useful in assessing the viability of the peat-plant environment. This test method does not apply to peat that is in paper or construction materials. Test Method D4972 is used for pH testing of soils and Test Method G51 is used for pH testing of soils for corrosion analysis (see Note 1 ). Note 1: These three standards are being intentionally kept separate for clarity at the request of the various subcommittees. 1.2 Units— The values given in SI units are to be regarded as the standard. No other units of measurement are included in this standard. 1.3 All measured and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 . 1.3.1 The procedures used to specify how data are collected/recorded and calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design. 1.4 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. 1.5 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 The pH of peat is a useful variable in determining the solubility of minerals, the mobility of ions in the peat, and assessing the viability of the peat-plant environment. pH measurements are made in both test water and a calcium chloride solution because the pH readings in test water can be modified by salts, such as fertilizer material, whereas the observed pH in calcium chloride solution is virtually independent of the initial amount of salts present in the peat. pH values obtained in a calcium chloride solution are usually about a 0.5 to 0.8 pH unit lower than measurements in test water due to release of more hydrogen ions by cation exchange. Both measurements are needed to fully define the character of the peat’s pH. 5.2 pH measurements are used in the agricultural, environmental, geotechnical, and natural resources fields. The pH of peat materials is helpful when evaluating a peat as a topsoil or growing medium for plants. Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.