This standard specifies the necessary procedures for the calculation of the density of liquefied natural gas (LNG), by means of the revised Kloseck-McKinley method, used to obtain the mass of the gas. In addition, it allows the calculation of the energy transferred from a vessel to a tank or vice versa, at reference conditions. The standard takes into account both the volume of the liquid and vapor phase involved during the transfer from/vessel to/tank.This standard applies to liquefied natural gases at a temperature between -180°C and -140°C and with a molecular mass between 16 and 30 kg/kmol.