Certified LPG Standards

Traceable calibration gases are necessary to calculate the composition and the calorific values of natural gas, refinery gas, biogas, etc. Several National Metrology Institutes are able to supply Primary Standards Gas mixtures to allow for GC and analyser calibration. VSL, Dutch Metrology institute (Netherlands) recently concluded a stability and consistency study on newly developed primary standards for calibration of Liquefied Petroleum Gas (LPG) measurement equipment. As the first National metrology Institute, VSL now offers certified reference standards to be used for calibration or QC purposes on site or in the laboratory. The newly developed standards are contained in 1000 cc constant pressure cylinders and typically contain ethane, iso- and n-butane and iso-pentane in a propane/propylene matrix. Due to the constant pressure cylinders, the liquid composition remains stable during the mixtures life time. The mixtures are prepared by the gravimetric technique employing state-of-the-art weighing facilities. Each mixture has an individual VSL certificate stating the composition and the associated uncertainty.