1.1 This International Standard deals with the determination of the anti-knock characteris ics of automobile fuels intended for spark-ignition machines, expressed in octane number. It specifies the use of the device and the operating procedure described in the Annual Compendium of ASTM Methods — Part 47. 1.2 The octane number of a motor fuel is determined by comparis n, following standard operating conditions , its tendency to detonation with those of reference fuel mixtures having a known octane number. This is achieved by varying the compression ratio, in order to obtain the normalized detonation intensity which is measured by an electronic detonation indicator. When the reading on the electronic detonation indicator is framed between those of two reference mixtures, the octane number of the sample is calculated by interpolation.
NBN T 52-161-1978 history
1978NBN T 52-161-1978 ("Motor fuels - Determination of knock characteristics- Research method