A Double Check Detector Assembly shall be installed on fire protection systems when connected to a potable water supply. 当消防系统连接到饮用水供应系统时，应该安装一个双止回阀总成。
An air gap provides the unobstructed, physical separation between the discharge end of a potable water supply line and an open receiving vessel. 在饮用水供应系统的排放末端和开敞的接受容器之间，气隙提供不被堵塞的硬件分离。
