The production of zero point gas is completely similar to the production of gas reference material, but the operation process can be simplified. Diluted gas in general use can be used as a "zero point" gas if the content of one or more impurities is below the minimum detection of the measuring instrument used in the analytical method.

The zero point gas is used to calibrate the zero point of the working curve with a given analysis method within a given content range. When it enters the instrument as the measured sample, within the measurement range selected by the instrument, only the response value of the instrument zero is presented, and no response signal beyond the preset zero is generated. For different detection methods and different detection instruments, the minimum detection limit will put forward different requirements for zero gas.

High purity gas is made into a zero point gas

If the total hydrocarbon content in high purity CO2 gas is measured by online analytical instrument, gas chromatography can be used to detect the hydrogen flame ionization detector (FID). Because of the strong basic effect of FID, when the zero-point gas calibration instrument with different matrix is used, it will lead to non-negligible error.