1.1 本试验方法包括使用自动蒸汽压仪测定37.8℃下液化石油气产品的蒸汽压 °C，汽液比0.5:1，压力200 kPa至1550 kPa，样品体积为3.33 毫升。 1.2 本试验方法适用于测定37.8℃以下液化石油气产品的蒸汽压 °C至70 °C，汽液比为0.1:1至4:1，压力高达3500 kPa；然而，试验方法的精度（参见第节 15 )仅在汽液比为0时确定。 5: 1，温度为37.8 °C，压力范围为300 kPa至1500 千帕。 注1: 本试验方法的目的不是测定液化石油气样品的真实蒸汽压，而是测定并报告37.8℃下液化石油气的蒸汽压 °C温度和0.5:1的汽液比作为试验方法 D1267号 方法 注2: 本试验方法不是真实蒸汽压法，如果存在氮或氦等溶解气体，则不会测量其全部贡献。轻气体对测量蒸汽压的贡献在很大程度上取决于试验温度、气体类型和试验的体积比。 1.3 以国际单位制表示的数值应视为标准值。 1.3.1 例外情况- 括号中包含非国际单位制，仅供参考。 1.4 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和健康实践，并确定监管限制的适用性。 有关特定警告声明，请参阅 附录X2 . ====意义和用途====== 5.1 液化石油气蒸汽压的信息与选择适当设计的储存容器、运输集装箱和客户使用设备有关，以确保这些产品的安全搬运。 5.2 出于安全考虑，液化石油气蒸汽压的测定非常重要，以确保在正常工作温度条件下不会超过存储、处理和燃料系统的最大工作设计压力。 5.3 对于液化石油气，蒸汽压可被视为产品中最易挥发物质含量的半定量测量。 5.4 本试验方法使用小样本量，不包括在高压下手动处理测量室。

1.1 This test method covers the use of automatic vapor pressure instruments to determine the vapor pressure of liquefied petroleum gas products at a temperature of 37.8 °C, vapor to liquid ratio of 0.5:1, and pressures from 200 kPa to 1550 kPa on a sample volume of 3.33 mL. 1.2 This test method is applicable to the determination of vapor pressures of liquefied petroleum gas products at temperatures from 37.8 °C to 70 °C, vapor to liquid ratios of 0.1:1 to 4:1, and pressures up to 3500 kPa; however, the precision of the test method (see Section 15 ) has only been determined for a vapor to liquid ratio of 0.5:1, at a temperature of 37.8 °C, and a pressure range from 300 kPa to 1500 kPa. Note 1: This test method is not intended to determine the true vapor pressure of LPG samples, but rather determine and report the vapor pressure of LPG at the 37.8 °C temperature and 0.5:1 vapor to liquid ratio as the Test Method D1267 method. Note 2: This test method is not a true vapor pressure method and will not measure the full contribution from any dissolved gases such as nitrogen or helium if they are present. The contribution of light gases to the measured vapor pressure is highly dependent on the test temperature, type of gas, and V/L ratio of the test. 1.3 The values stated in SI units are to be regarded as standard. 1.3.1 Exception— Non-SI units are included in parentheses for information only. 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 specific warning statements, see Appendix X2 . ====== Significance And Use ====== 5.1 Information on the vapor pressures of liquefied petroleum gas is pertinent to selection of properly designed storage vessels, shipping containers, and customer utilization equipment to ensure safe handling of these products. 5.2 Determination of the vapor pressure of liquefied petroleum gas is important for safety reasons to ensure that the maximum operating design pressures of storage, handling, and fuel systems will not be exceeded under normal operating temperature conditions. 5.3 For liquefied petroleum gases, vapor pressure can be considered a semi-quantitative measure of the amount of the most volatile material present in the product. 5.4 This test method uses a small sample volume and excludes any manual handling of a measuring chamber under high pressure.