Drencher systems

Drencher systems are installed to protect against radiated heat or to flood a high risk process with water for... 

The controlling valves for drencher systems are located in accessible positions on or near ground level but away from the adjacent fire risk. The valves are secured against unauthorised interference, protected from frost and clearly indicated. 

Drenchers normally operate on the alternate system, and are more economical in the use of water than open drenchers, since only those heads that operate are required, and the pressure is maintained more efficiently. There are three main types of drencher system ... 

Figure 9.63 The operation of a protective roof drencher system...

Figure 4.2.1 I Diagram of a typical drencher (deluge) system (Manual of Firemanship. Courtesy the Controller, Stationery Office)...

Automatic fire extinguishing systems such as sprinklers, drenchers or gas systems operate when the heat of the fire in the region of a detector head reaches predetermined levels and cause the seal in the detector head to fracture releasing the extinguishant. These systems can incorporate a facility to raise the alarm. 

While a sprinkler system protects a building from internal fire, drenchers are located on roofs and over windows and external openings to protect the building from damage by exposure to a fire in adjacent premises. 

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