1.1 这些试验方法涵盖了液体工业化学品表观比重的测定。两种测试方法如下: 1.1.1 试验方法A， 比重，表观比重，通过比重计测定。 1.1.2 试验方法B， 比重计测定的表观比重。 注1: 试验方法 D4052 描述了一种仪器程序。 1.2 在一般用法中，术语比重（表观）被理解为比重或相对密度。 1.3 以国际单位制表示的值应被视为标准值。这些测试方法中不包括其他测量单位，但华氏度（°F）除外 5.1 作为可能的工业规格单位的示例。 1.4 本标准并不旨在解决与其使用相关的所有安全问题（如果有的话）。 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。有关本规范中使用的所有材料，请参阅当前的OSHA法规、供应商的安全数据表和当地法规。 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》中确立的国际公认的标准化原则制定的。 =====意义和用途====== 4.1 表观比重可用作确定化学物质特性的定性测试。 它可用于计算已知重量的产品所占的体积，或根据其体积计算产品的重量。它可用于确定纯化学品的二元混合物的组成。对于大多数精炼工业化学品，比重（表观）在定义质量方面的价值很小，尽管它可能会检测到严重污染。 4.2 在所述的两种测试方法中， 1.1.2 )是最准确和精确的。因此，在发生争议时，这是首选方法。液体比重计法（试验方法A， 1.1.1 )是最不准确和精确的，但它也是最简单、最快的，在许多方面通常都是完全令人满意的。如果样品太粘稠，液体比重计无法自由浮动，则应使用比重瓶测试方法。

1.1 These test methods cover the determination of the specific gravity, apparent, of liquid industrial chemicals. Two test methods are covered as follows: 1.1.1 Test Method A, specific gravity, apparent, by means of a hydrometer. 1.1.2 Test Method B, specific gravity, apparent, by means of a pycnometer. Note 1: Test Method D4052 describes an instrumental procedure. 1.2 In common usage the term specific gravity, apparent, is understood to mean specific gravity or relative density. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in these test methods with the exception of Fahrenheit (°F) in 5.1 as an example of a possible industrial specification unit. 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. Consult current OSHA regulations, suppliers’ Safety Data Sheets, and local regulations for all materials used in this specification. 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 ====== 4.1 Specific gravity, apparent, may be used as a qualitative test in establishing the identity of a chemical. It may be used to calculate the volume occupied by a product whose weight is known, or to calculate the weight of a product from its volume. It may be used to determine the composition of binary mixtures of pure chemicals. In the case of most refined industrial chemicals specific gravity, apparent, is of minimal value in defining quality, although it may detect gross contamination. 4.2 Of the two test methods described, the pycnometer method (Test Method B, 1.1.2 ) is the most accurate and precise. For this reason it is the preferred method in case of disputes. The hydrometer method (Test Method A, 1.1.1 ) is the least accurate and precise, but it is also the simplest and fastest to perform and is often entirely satisfactory for many purposes. If the sample is too viscous to permit the hydrometer to float freely, the pycnometer test method should be used.