1.1 本规范涵盖了配备乙醇燃料混合物柔性燃料火花点火发动机的地面车辆中使用的乙醇和汽油汽车燃料混合物的要求。根据本规范生产的燃油包含51 % 至83 % 按体积计算的乙醇。这种燃料用于灵活燃料汽车，有时在零售时被称为“乙醇弹性燃料” 附录X1 讨论指定属性的意义。 1.2 乙醇燃料混合物的蒸汽压随季节气候变化而变化。蒸汽压在较低温度下升高，以确保足够灵活的燃料车可操作性。乙醇含量和碳氢化合物混合料的选择由混合器进行调整，以满足这些蒸汽压要求。 1.3 本规范以前涵盖了汽车火花点火发动机用燃料乙醇（Ed70-Ed85），商业上也称为E85。术语“燃料乙醇”已更改为“乙醇燃料混合物”，以区分本产品与变性燃料乙醇规格 D4806 . 为了促进满足季节蒸汽压要求的乙醇燃料混合物的混合，建立了一个新的较低的最低乙醇含量。 1.4 美国政府制定了各种替代燃料计划。这些项目使用的替代燃料的许多定义可能比本规范的要求更具限制性。 看见 4.1.2.1 有关含乙醇的替代燃料的更多信息。 1.5 以国际单位制表示的数值应视为标准值。国际单位制后括号中给出的值仅供参考，不被视为标准值。 1.6 以下安全危险警告仅适用于试验方法部分， 8.1.8 ，符合本规范。 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。 1.7 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。

1.1 This specification covers the requirements for automotive fuel blends of ethanol and gasoline for use in ground vehicles equipped with ethanol fuel blend flexible-fuel spark-ignition engines. Fuel produced to this specification contains 51 % to 83 % by volume ethanol. This fuel is for use in flexible-fuel vehicles and is sometimes referred to at retail as “Ethanol Flex-Fuel.” Appendix X1 discusses the significance of the properties specified. 1.2 The vapor pressure of ethanol fuel blends is varied for seasonal climatic changes. Vapor pressure is increased at lower temperatures to ensure adequate flexible-fuel vehicle operability. Ethanol content and selection of hydrocarbon blendstock are adjusted by the blender to meet these vapor pressure requirements. 1.3 This specification formerly covered Fuel Ethanol (Ed70-Ed85) for Automotive Spark-Ignition Engines, also known commercially as E85. The nomenclature “fuel ethanol” has been changed to “ethanol fuel blends” to distinguish this product from denatured fuel ethanol Specification D4806 . To facilitate blending of ethanol fuel blends that meet seasonal vapor pressure requirements, a new lower minimum ethanol content has been established. 1.4 The United States government has established various programs for alternative fuels. Many of the definitions of alternative fuel used by these programs may be more restrictive than the requirements of this specification. See 4.1.2.1 for additional information on alternative fuels containing ethanol. 1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.6 The following safety hazard caveat pertains only to the test method portion, 8.1.8 , of this specification. 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. 1.7 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.