ISO 5163:2014使用标准单缸、四冲程循环、可变压缩比、化油器、恒速运行的CFR发动机，根据辛烷值的任意刻度，确定了液体火花点火发动机燃料的额定值。发动机辛烷值（MON）是衡量汽车发动机在恶劣运行条件下发动机燃料爆震特性的一种方法。发动机辛烷值通过使用与航空方法辛烷值或性能值（稀薄混合气航空评级）相关的方程式，提供了航空活塞发动机中航空燃料爆震特性的测量值。 ISO 5163:2014适用于从0周一到120周一的整个范围，但工作范围为40周一到120周一。典型的发动机燃油测试范围为80至90个月。典型的航空燃油测试范围为98周一至102周一。

ISO 5163:2014 establishes the rating of liquid spark-ignition engine fuel in terms of an arbitrary scale of octane numbers using a standard single-cylinder, four-stroke cycle, variable-compression ratio, carburetted, CFR engine operated at constant speed. Motor octane number (MON) provides a measure of the knock characteristics of motor fuels in automotive engines under severe conditions of operation. The motor octane number provides a measure of the knock characteristics of aviation fuels in aviation piston engines, by using an equation to correlate to aviation-method octane number or performance number (lean-mixture aviation rating). ISO 5163:2014 is applicable for the entire scale range from 0 MON to 120 MON, but the working range is 40 MON to 120 MON. Typical motor fuel testing is in the range of 80 MON to 90 MON. Typical aviation fuel testing is in the range of 98 MON to 102 MON.