You should number all the instruments and valves, and the instruments should be shown in a circle enclosing the usual identifying codes, and a bar if it is displayed in the control room.

• 你们应该把所有的仪表和阀门编号，并且仪表应该表达在一个圆圈里，包括通常的标记码，如果要在控制室显示,再加一短横标记。