As per pipe water in reserve in case there is not enough and you want to use the water from the outside of the building can be plugged in from the point, fire engine or fire hose up to the fire in the building.
The per capita water reserves in case of insufficient water in the building and use of water outside the building. You can connect from this point The fire truck Fire extinguisher or water hose up to a fire in a building on the other.
As a backup in case of water pipe connector building is not enough, and want to use the water from outside the building, can connect from this point from a truck. Or stand pipe up to use fire in the building again.