Entering the 8th St–New York University subway station just south of Astor Place on Broadway, commuters must pass through a full height turnstile in order to reach the platform. The process involves, first, swiping your MetroCard through the card reader, situated to a person’s right, approximately three feet from the ground. The gate will then give you a high pitched tone and, if your card is read correctly and you have sufficient fare, a green light indicating that it’s OK to proceed through the turnstile. The interior metal spokes can then be pushed to rotate 120°, allowing one person through at a time.


I wanted to observe how people interact with this gate as it’s one I use on a regular basis and the experience varies. Obviously, one advantage to the system is that it allows for more points of entry into a station without requiring station attendants to watch for turnstile jumpers (although, pairs do occasionally squeeze through the full height turnstile together). So I spent some time watching people move through the turnstile, noting the rate of success and any recurring issues that arose. I was surprised to find that roughly nine out of ten people move through the gate in one sequence of motion. That feels like a better success rate than my own. Only one person was wrongly turned away by a turnstile rotation that ended before enough clearance was established to pass through. The rest either needed to swipe their MetroCard again, or the card was expired or had insufficient fare.


Easily the most common problem was the system’s way of communicating whether or not the card swipe is approved. There are two reasons for this, related to the system’s two forms of feedback: a tone and a green, backlit sign. The first is that, even with careful listening, it’s very difficult to distinguish between the tone of an accepted swipe and that of a rejected one. Both are exactly the same pitch and seem to be differentiated only by how many times the beep repeats—a subtlety completely obscured by the reverb of the space. Thus, the beep serves only to confirm that the card has been swiped, nothing more. You’d think that, at least for those who aren’t blind, this would be compensated for by the green “Go” sign that lights up when your card swipe is validated. I find, though, that its position is a bit too far forward in the motion of moving through the gate. As a result, people are often beyond the sign by the time they realize they need to swipe their card again, requiring them to walk back two or three steps and try again. This is how backups tend to occur at the entrance.
I would propose establishing two distinct pitches and shifting the placement of the “Go” light. This would allow for clearer interaction and speed the flow of commuter traffic through the turnstile. Ideally, the whole system would be unnecessary because people would simply pay trustworthily. It would be interesting, though, to study how many do if the gate were scaled down.