Mantraps
Mantraps - physical controls within a building that serve as a gateway from either outside of a building, or an unsecured part of a building, to a secured part of a building.
Purpose: To capture people who enter a building illegally, often tailgating.
Tailgating - the act of someone entering a building without credentials right behind someone who has credentials for a building
They cannot get out until a security guard or a similar authoritative figure questions the individual on the reasons for attempting to enter a building.