1.1 本试验方法包括测定市售甲醛溶液的酸度。 1.2 为了确定使用该试验方法观测值或计算值是否符合相关规范，应根据实践中的四舍五入方法，将试验结果四舍五舍五入到表示规范限值时使用的右最后一位数字中的“最接近的单位” E29 。 1.3 以国际单位制表示的数值应视为标准。本标准中不包括其他计量单位。 1.4 有关危险信息和指南，请参阅供应商的安全数据表。 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）。 本标准的使用者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。 具体危害说明见第节 7. 。 1.6 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》中确立的国际公认的标准化原则制定的。 ===意义和用途====== 4.1 该测试方法提供了甲醛溶液中酸度（以甲酸形式）的测量。这些测量结果可用于规范验收。

1.1 This test method covers the determination of the acidity of commercially available formaldehyde solutions. 1.2 For purposes of determining conformance of an observed or a calculated value using this test method to relevant specifications, test result(s) shall be rounded off “to the nearest unit” in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29 . 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 For hazard information and guidance, see the supplier’s Safety Data Sheet. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 7 . 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 This test method provides a measurement of acidity (as formic acid) in formaldehyde solutions. The results of these measurements can be used for specification acceptance.