Scope and Purpose This publication describes dynamic and static measurement systems used to measure liquefied petroleum gas (LPG) in the relative density range of 0.350 to 0.637 (see Chapter 11.2.2). The physical properties of the components to be measured and the mixture composition of liquefied petroleum gas should be reviewed to determine the measurement system to be used. Various systems and methods can be used in measuring the quantity of product, and mutual agreement on the system and method between the contracting parties is required. This publication does not endorse or advocate the preferential use of any specific type of meter or metering system. Further, this publication is not intended to restrict the future development of meters or measuring devices, nor to in any way affect metering equipment already installed and in operation. This publication serves as a guide in the selection, installation, operation, and maintenance of measuring systems applicable to liquefied petroleum gases and includes functional descriptions for individual systems.