Harmonisation
EUREGA – The harmonised reference value
pigsar™ is the operator of the national standard for high-pressure natural gas flow metering. All meters tested at pigsar™ can be traced back to the SI base units.
Other independent calibration chains in Europe are operated in the Netherlands, France and Denmark. Since 1999 there has been an agreement between the national metrological institutes to compare these calibration chains and eliminate any differences. This agreement, also referred to as "harmonisation", was initially concluded between the Nederlands Meetinstituut (NMi) and the Federal Institute of Physics and Metrology (PTB). In 2004, the French Laboratoire National de Métrologie et d’Essait (LNE) joined the agreement, followed by FORCE, the institute nominated by Denmark, in 2013.
As there are currently no other national standards in Europe, the harmonisation has in effect created the "European High-Pressure Natural Gas Cubic Metre". This is why since 2013 the reference level has been called EuReGa: European Reference for Gas Metering.
EuReGa ensures that any differences between calibration chains are reduced to a minimum. This is done by regularly comparing participating test facilities using transfer meters sized DN100 to DN400.