NBN ISO 6578:2021

This document specifies the calculation procedure to convert the volume of liquefied petroleum gas
(LPG) and liquefied natural gas (LNG) under the conditions at the time of measurement to the equivalent
volume of liquid or vapour at the standard condition, i.e. 15 °C and 101,325 kPaA, or to the equivalent
mass or energy (calorific content). It applies to the quantities of refrigerated hydrocarbon liquids
stored in or transferred to/from tanks and measured under static storage conditions. Calculation of
pressurized gases is out of the scope of this document.