This European Standard specifies a method for the determination of the vapour pressure@ exerted in vacuo@ by volatile@ low viscosity petroleum products@ components@ ethanol blends up to 85 % (V/V)@ and feedstocks using a variable volume chamber. A dry vapour pressure equivalent (DVPE) is calculated from the vapour pressure. The conditions used in the test described in this standard are a vapour-to-liquid ratio of 4:1 and a test temperature of 37@8 ?? This method is also applicable to different vapour to liquid ratios and different temperatures but the precision in Clause 15 does not apply. This procedure calculates the partial pressure of the air dissolved in the test portion during the triple expansion process. The equipment is not wetted with water during the test@ and the method described is therefore suitable for testing samples with or without oxygenates; no account is taken of dissolved water in the sample. This document is applicable to fuels containing oxygenated compounds up to the limits stated in the relevant EC Directive 85/536/EEC [4]@ and for ethanol-fuel blends up to 85 % (V/V) ethanol. NOTE For the purposes of this European Standard@ the terms ??% (m/m)??and ??% (V/V)?? are used to represent the mass and volume fractions respectively. WARNING ?? The use of this Standard can involve hazardous materials@ operations and equipment. This Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of users of this standard to take appropriate measures to ensure the safety and health of personnel prior to application of the standard@ and fulfil statutory and regulatory requirements for this purpose.