1.1本试验方法描述了用气相色谱法分析乙苯中常见杂质和乙苯纯度。测定的杂质包括非芳烃、苯、甲苯、二甲苯、异丙苯和二乙苯异构体。 1.2本试验方法适用于浓度为0.001%至1.000%的杂质和纯度为99%或更高的乙苯。在此水平下，可能无法检测到二甲苯。 1.3以下内容适用于本标准中的所有规定限值:为了确定是否符合本标准，应将观察值或计算值四舍五入到最后右侧的“最接近的单位”- 根据实施规程E29的四舍五入方法，用于表示规范限值的手写数字。 1.4本标准无意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和健康实践，并确定监管限制的适用性。有关具体的危险说明，请参阅第7节。

1.1 This test method describes the analysis of normally occurring impurities in, and the purity of, ethylbenzene by gas chromatography. Impurities determined include nonaromatic hydrocarbons, benzene, toluene, xylenes, cumene, and diethylbenzene isomers. 1.2 This test method is applicable for impurities at concentrations from 0.001 to 1.000% and for ethylbenzene purities of 99% or higher. At this level, -xylene may not be detected. 1.3 The following applies to all specified limits in this standard: for purposes of determining conformance with this standard, an observed value or a calculated value 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. 1.4 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 and health practices and determine the applicability of regulatory limitations prior to use. For a specific hazard statement, see Section 7.