Fixed hydrant networks are a system of pipes, valves, fire hydrants and accessories installed in a building or structure, arranged in such a way that the water coming from the fire hydrants can be discharged through hoses and lances with in order to extinguish a fire and thus protect the building, its occupants and the goods contained therein.

As water hydrant systems are essential components of fire fighting, they must be tested and inspected periodically so that they are always ready. The tests must be carried out before the certification of work and afterwards at suitable intervals to verify its operation. There is no general rule about the frequency of these tests. These tests should check if the system works according to its initial specifications.