1.1 本试验方法用于测量a 5的pH值 % 每体积质量（m/V）二氧化硅/水悬浮液或机械分散液，表示二氧化硅的相对酸碱度。 1.2 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。 1.3 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。 1.4 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====== 3.1 众所周知，通过本试验方法测量的二氧化硅pH值水平会影响某些橡胶化合物的硫化。参考测试方法 E70 更全面地了解pH值和更详细的pH测量程序。

1.1 This test method is used to measure the pH of a 5 % mass per volume (m/V) silica/water suspension or mechanical dispersion and is indicative of the relative acidity or alkalinity of the silica. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 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. 1.4 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 ====== 3.1 The pH level of silica, as measured by this test method, is known to affect the vulcanization of some rubber compounds. Refer to Test Method E70 for a fuller understanding of pH and a more detailed procedure for making pH measurements.