How to distinguish between two-wing revolving door and three-wing revolving door?
You count the number of door leaves in the revolving area. Two door leaves are two wings, three door leaves are three wings, and at most four door leaves are four-wing revolving doors.
After the two-wing revolving door stops parallel to the wall, there is a sliding door in the middle, which can be used as an emergency passage.
The three\four-wing revolving door can overlap the door leaf and push it to one side, and can also be used as an emergency passage.