A valve is a device that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways.
The word is derived from the Latin valva, the moving part of a door, in turn from volvere, to turn, roll. The simplest, and very ancient, valve is simply a freely hinged flap which drops to obstruct fluid (gas or liquid) flow in one direction, but is pushed open by flow in the opposite direction.
Modern control valves may regulate pressure or flow downstream and operate on sophisticated automation systems. Źródło: https://en.wikipedia.org/wiki/Valve
Notification of such a failure of the hydraulic, which may require emergency hydraulic arrival is done by phone, and the arrival of such an emergency can occur within several minutes.In the phone book you can find phone numbers for such branches emergency hydraulic, which are open around the clock and seven days a week, including holiday periods.
At the same time the hydraulic assistance can apply the owners of private houses, in which there have been some failures.Depending on the type of failure, they can order the execution of hydraulic works in normal mode, or call the emergency hydraulic. Such hydraulic ambulance is able to reach a flooded home, even during the weekend.