GB/T 5274.1-2018 Active

This part of GB/T 5274 specifies the method of preparing bottled calibration gas mixtures by weighing, and the material fraction (mole fraction) of one or more components of the calibration gas mixture can be traced to a standard value. This part also specifies the calculation method of the uncertainty of the mole fraction of each component, which requires evaluating the uncertainty contributions of the following factors when calculating the uncertainty: weighing process, component purity, stability of the gas mixture, and verification of the final gas mixture. This part is only applicable to the preparation of gaseous or fully vaporizable component gas mixtures, and the components can be introduced into gas cylinders in gaseous or liquid form. This part covers the preparation of binary or multi-component gas mixtures (including natural gas). This part does not include methods for batch preparation of multiple gas mixtures in a single process. In order to determine the shelf life (maximum storage period) of the gas mixture, this part specifies a method for stability evaluation, but this method is not applicable to the evaluation of the stability of components that react with each other. This part also specifies methods for quantitative analysis and evaluation of impurities in each raw material (gas or liquid) used to prepare the gas mixture.