Security cameras on the Yamanote Line Immediately test footage from management rooms, and many others. | NHK

Regarding the safety cameras put in in Yamanote Line vehicles, JR East has determined so as to add a perform that permits the pictures to be immediately checked from outdoors the prepare, comparable to within the management room, with the intention to strengthen its response to troubles. To shield passenger privateness, footage can solely be considered when the emergency name system is activated.

Source