There shall be semi-auto change over system in the gas yard and main pressure valve and relief valves should be located outside the lab building.
There shall be semi-auto change over system in the gas yard and main pressure valve and relief valves should be located outside the lab building.
安装半自动转换阀控制气瓶更换，主要的控制阀门和减压阀门都安装在实验室外。