Abstract
The methods for the gas reference materials preparation in Laboratory of Gas Reference Materials were presented. The attention was paid to limitations of methods and the sources of uncertainty. Additionally calibration of the gas reference materials was described. In the GUM the gas reference materials are made in accordance with PN-EN ISO 6142 and PN-EN ISO 6145-7. The gas standards are calibrated according to PN-EN ISO 6143 using the chromatographic method and by using gas analyzers.


