A system for measuring and correcting flow measurements of a gas containing saturated water vapor, comprising: a pressure sensor configured to sense a pressure of the gas ; a differential pressure sensor configured to sense a differential pressure related to flow of the gas ; a temperature sensor configured to sense a temperature of the gas ; measurement circuitry configured to correct flow measurements of the gas by providing flow measurements of the gas compensated for saturated water vapor in the gas based upon the measured pressure, differential pressure and temperature, wherein the measurement circuitry determines a correction factor for a desired component in the gas , characterised in that : the measurement circuitry uses curve fitting coefficients to determine the concentration of water vapor in the gas , the system includes a user input for selecting desired components of the gas for which a correction factor is provided, and the flow measurements of the gas are compensated for saturated water vapor by correcting a mole fraction of a dry component of the gas based on a mole fraction of water vapor, using the corrected mole fraction of the dry component of the gas to determine a molecular weight of the gas with water vapor and using the molecular weight of the gas with water vapor to produce the flow measurements of the gas compensated for saturated water vapor. a pressure sensor configured to sense a pressure of the gas ; a differential pressure sensor configured to sense a differential pressure related to flow of the gas ; a temperature sensor configured to sense a temperature of the gas ; measurement circuitry configured to correct flow measurements of the gas by providing flow measurements of the gas compensated for saturated water vapor in the gas based upon the measured pressure, differential pressure and temperature, wherein the measurement circuitry determines a correction factor for a desired component in the gas , characterised in that : the measurement circuitry uses curve fitting coefficients to determine the concentration of water vapor in the gas , the system includes a user input for selecting desired components of the gas for which a correction factor is provided, and the flow measurements of the gas are compensated for saturated water vapor by correcting a mole fraction of a dry component of the gas based on a mole fraction of water vapor, using the corrected mole fraction of the dry component of the gas to determine a molecular weight of the gas with water vapor and using the molecular weight of the gas with water vapor to produce the flow measurements of the gas compensated for saturated water vapor. the measurement circuitry uses curve fitting coefficients to determine the concentration of water vapor in the gas , the system includes a user input for selecting desired components of the gas for which a correction factor is provided, and the flow measurements of the gas are compensated for saturated water vapor by correcting a mole fraction of a dry component of the gas based on a mole fraction of water vapor, using the corrected mole fraction of the dry component of the gas to determine a molecular weight of the gas with water vapor and using the molecular weight of the gas with water vapor to produce the flow measurements of the gas compensated for saturated water vapor. <EOS>