Section 37(1) in The Delhi Metro Airport Express Line, General Rules, 2010
(1)Door open indicator - (a) when platform screen door or platform edge door is under opening and closing process, the door opening indicator flashes and chime is activated;(b)when platform screen door or platform edge door is under fully opened position, the door opening indicator is illuminated and chime is deactivated;(c)when platform screen door or platform edge door is under closed and locked position, the door opening indicator is extinguished and chime is deactivated.
