GB/T 5275-2005 in English

本标准规定了用渗透原理制备校准用混合气体的方法。它是一种动态配气方法。通常所需组分在混合气体中的浓度范围为10-9～10-5(体积分数)，组分浓度的准确度可以达到2%(实际上，浓度单位也可以用μg/m3表示)。由于在这样低的浓度范围内要保持混合气体的浓度稳定不变是困难，因此校准用混合气应在临用时制备，并且输送混合气体的管路应尽可能短。

Scope

This standard specifies the method of preparing mixed gas for calibration using the principle of osmosis. It is a dynamic gas distribution method. Generally, the concentration range of the required components in the mixed gas is 10^-9～10^-5 (volume fraction), and the accuracy of the component concentration can reach 2% (in fact, the concentration unit is also It can be expressed in μg/m³). Since it is difficult to keep the concentration of the mixed gas stable in such a low concentration range, the mixed gas for calibration should be prepared immediately before use, and the pipeline for delivering the mixed gas should be as short as possible.