When a New York City Transit subway train pulls into the station, there is a prescribed spot on the platform where it must stop and there is no margin for error. If the train operator pulls up short, the rear of the train could still be out in the tunnel and if the train slides out of the station at the front end even by a few feet – well, you get the idea.

In either case, the conductor should not open the doors. But how does the conductor know if the train has stopped at the proper location? It’s all in black and white. The conductor’s indication board is a black and white striped board of wood situated in the middle of the platform and facing the train. When the train is aligned properly, the board is directly in front of the conductor’s window and he knows that it is safe to open the doors.

The boards have been a staple on subway platforms since the First World War when the system was shifting to multiple unit door control. Prior to that, there was one subway conductor between every two cars. The boards were installed when technology advanced to the point where one conductor could operate all doors on a train. Conductors, however, were not required to acknowledge the boards. That changed back in September of 1996 when conductors were first required to physically acknowledge the “zebra boards,” by pointing to them before opening the doors.

This was done to create an additional level of safety. By pointing at the board, the conductor acknowledges that the train is stopped at the proper spot on the platform. While there is some fogginess over just who made it a requirement, there is absolutely no argument over where it originated – Japan.

It seems that Japanese railway operations personnel are required to point “acknowledge” many parts of their operation, including speed indicators, upcoming wayside signals, and the train’s position when stopped at a platform.

“The practice of having our conductors acknowledge the boards is one component of safeguarding our customers,” said NYC Transit President Carmen Bianco. “It is a simple gesture that goes a long way toward reinforcing safe operating practices.”

With the introduction of the New Technology fleets beginning in 1999, yet another layer of protection has been added. All new trains include the installation of Door Enable systems. This system requires the train operator to ‘enable’ the conductor by activating the door controls only on the platform side of the train after it is properly berthed.

So, the next time you see your subway conductor extend his hand out the window of the train, he is pointing the way - to safety.