1.1 本规范涵盖了配备甲醇柔性燃料和专用甲醇火花点火发动机的地面车辆中使用的甲醇和汽油混合汽车燃料的要求。根据本规范生产的燃油包含51 % 至85 % 按体积计算的甲醇。这种燃料有时在零售中被称为“M85” 附录X1 讨论指定属性的意义。 附录X2 介绍了甲醇燃料混合物（M51–M85）光度测试程序（火焰可见度）的开发现状。 1.2 甲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，以确保车辆具有足够的可操作性和安全性。 甲醇含量和汽油混合器的选择由混合器进行调整，以满足这些蒸汽压要求。 1.3 美国政府制定了各种替代燃料计划。这些项目使用的许多替代燃料的定义可能比本规范的要求有更多或更少的限制。看见 附件A1 有关含甲醇的替代燃料的更多信息。 1.4 以国际单位制表示的数值应视为标准。 1.4.1 例外情况- 非国际单位制仅供参考。在大多数情况下，美国联邦法规规定了非国际单位制。 1.5 以下预防性警告仅适用于试验方法部分—— 附录X2 符合本规范的要求。 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。 1.6 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 methanol and gasoline for use in ground vehicles equipped with methanol-capable flexible-fuel, and dedicated methanol spark-ignition engines. Fuel produced to this specification contains 51 % to 85 % by volume methanol. This fuel is sometimes referred to at retail as “M85.” Appendix X1 discusses the significance of the properties specified. Appendix X2 presents the current status in the development of a luminosity test procedure (flame visibility) for methanol fuel blends (M51–M85). 1.2 The vapor pressure of methanol fuel blends is varied for seasonal climatic changes. Vapor pressure is increased at lower temperatures to ensure adequate vehicle operability and safety. Methanol content and selection of gasoline blendstocks are adjusted by the blender to meet these vapor pressure requirements. 1.3 The United States government has established various programs for alternative fuels. Many of the definitions of alternative fuel used by these programs can be more or less restrictive than the requirements of this specification. See Annex A1 for additional information on alternative fuels containing methanol. 1.4 The values stated in SI units are to be regarded as the standard. 1.4.1 Exception— Non-SI units are provided for information only. In most cases, U.S. federal regulations specify non-SI units. 1.5 The following precautionary caveat pertains only to the test method portions– Appendix X2 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. 1.6 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.