Why are there glass doors in Nanning subway station?

Subway glass screen door (also known as platform screen door or security door) refers to the way to close the subway platform and train boarding and disembarking space with glass curtain wall on the platform. When the train arrives at the station, open the electric door on the glass curtain wall for passengers to get on and off.

The main purpose is to prevent passengers from accidents, save energy and prevent the temperature loss of platform air conditioning.