1.1 本规范定义了气体燃料的最低燃料质量要求，该气体燃料主要由与高达10%的氢气混合的甲烷组成 2 )当用作内燃机燃料时按体积计。 1.2 该规范定义了将氢气与天然气、沼气或可再生天然气(RNG)混合，然后压缩成压缩天然气(CNG)以用作机动车辆中内燃机的燃料的标准。 1.3 燃料中氢气的总体积分数应由天然气、沼气或可再生气体中包含的氢气和掺入燃料混合物中的任何额外氢气组成。 1.4 本规范涵盖了两种燃料等级，由其计算的甲烷数(MNc)和最大允许氢气体积分数定义。它们描述如下: 1.4.1 等级MNc65 S5 H10- 含有高达5 ppm(v)硫、高达10%体积氢并满足65的最小MNc的共混物。 1.4.2 等级MNc75 S5 H10- 含有高达5 ppm(v)硫、高达10%体积氢并满足75的最小MNc的共混物。 1.5 本规范涵盖了设计用于机动车辆的内燃机的需求。 1.6 本规范适用于作为压缩气体输送到机动车辆车载燃料箱中的燃料。 1.7 本规范不是天然气管道标准；这些要求由国家和地区关税决定。 1.8 单位- 以SI单位表示的值将被视为标准值。SI单位后括号中给出的值仅供参考，不被视为标准值。1.9 本标准并不旨在解决与其使用相关的所有安全性问题（如果有）。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法规限制的适用性。 1.10 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》中确立的国际公认的标准化原则制定的。

1.1 This specification defines the minimum fuel quality requirements for gaseous fuels consisting primarily of methane blended with up to 10 % hydrogen (H 2 ) by volume when used as an internal combustion engine fuel. 1.2 This specification defines the criteria for blending hydrogen with natural gas, biogas, or renewable natural gas (RNG) and then compressed into compressed natural gas (CNG) for use as a fuel for internal combustion engines in motor vehicles. 1.3 The total volume fraction of hydrogen within the fuel shall consist of hydrogen contained in the natural gas, biogas, or renewable gas and any additional hydrogen blended into the fuel mixture. 1.4 This specification covers two fuel grades defined by their calculated methane number (MNc) and the maximum allowed volume fraction of hydrogen. They are described as follows: 1.4.1 Grade MNc65 S5 H10— A blend with up to 5 ppm(v) sulfur, up to 10 % hydrogen by volume, and meeting a minimum MNc of 65. 1.4.2 Grade MNc75 S5 H10— A blend with up to 5 ppm(v) sulfur, up to 10 % hydrogen by volume, and meeting a minimum MNc of 75. 1.5 This specification covers the needs of internal combustion engines designed for use in motor vehicles. 1.6 This specification applies to the fuel as delivered into the on-board fuel tanks of a motor vehicle as a compressed gas. 1.7 This specification is not a natural gas pipeline standard; those requirements are determined by national and regional tariffs. 1.8 Units— 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. 1.9 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. 1.10 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.