also referred to as the u201c displacement volume u201d is used to calculate the injected mass mi of testing fluid this is done by multiplying the displacement volume vm by the density of the testing fluid however the density of the testing fluid in the measuring chamber 45 on the one hand depends on the temperature t block 82 and on the other hand depends on the pressure p block 84 which prevail in the testing fluid in the measuring chamber 45 these are detected by the pressure sensor 50 and the temperature sensor 46 and based on the detected values in block 80 first the density prevailing in the testing fluid in the measuring chamber 45 is determined at the detected pressure p and the detected temperature t and based on this density the injected mass mi is determined based on the actually injected mass mi of testing fluid which has been injected into the measuring chamber 45 in block 86 a comparison or norm volume vnorm is calculated based on a determined pressure pnorm and a determined temperature tnorm block 88 this comparison or norm volume vnorm is particularly well suited for comparing different injections and for comparing different injection systems 32 the method depicted in fig2 ends at block 92 the device shown in fig1 and the method shown in fig2 can considerably improve the precision in the calculation of a volume injected into the measuring chamber 45 under defined norm conditions norm temperature and norm pressure and.