Recently I got trapped in a revolving door. If you have read Don Norman's "Design of everyday things", you already know that doors as simple as their design appears can be a rich source of usability limitations. My experience starts with a night out. After a wonderful dinner at a restaurant, we wanted to go to a cocktail bar. As I was short of money I wanted to withdraw some from a cash machine. The entrance was a huge revolving door (upper photo). The door consisted of two large segments. Just as I wanted to get in some people came out of the revolving door. It was still moving, so I quickly jumped in the empty half.
The door moved further, but suddenly stopped in the middle where it was not possible to reach any exit. I waited a bit, but nothing happened. Then I tried pushing the door unsuccessfully and I started feeling slightly nervous - What are you supposed to do when you get stuck in the middle of a revolving door at night when no one is around? A thorough look around revealed a green sign on the center post in the middle of the revolving door (left photo). The sign appeared to show that something needs to be pushed in order to open the door. So I tried pushing the in different directions and locations, but nothing happened. I felt helpless. Then I discovered another sign (right photo). Red letters on a white background - it looked like an alarm sign, but showed the promising word "Door opener". The red letters made me think about an alarm and I tried pushing again and looked for other options. After I could not think of anything else I finally pressed the button. There was no alarm sound, but the door started moving again and I could go out.It appears that the door stopped in the middle as a protection mechanism. It was late after the opening hours of the bank and I did not use a card to activate the door. That's why it stopped moving in the middle. Thinking of the design of the sign next to the button that opened the door and its position in the periphery of the door I'm quite sure that I'm not the only person who got trapped for a bit.