From this part, it looks like an underground garage plane.
The room above the wall should be the equipment room, and the door on the wall is open (downward).
The right wall is a firewall separating the left and right fire zones.
The green thick dotted line is a steel fire shutter.
Gray stripes are open drains covered with grids. In case of fire, the fire shutter is put down, and the nozzle for lowering the temperature of the steel shutter sprays water on the surface of the shutter. When the water reaches the ground, it is discharged from the drain.
Seen from this angle, the thin gray dotted line is like a car line, and the arc part indicates the turning radius.
This representation does not specify the driving direction, so it is suggested to use the arrow of the vehicle dealership to indicate the driving direction, which is simpler and clearer.