Medium Velocity (MV) systems are mainly used to protect structures, plant, and storage vessels from radiated heat and direct flame impingement.

Typical applications include:

• The complete external surface protection of bulk liquified gas pressure vessels to prevent container failure and the resultant Boiling Liquid Expanding Vapour Explosion (BLEVE).
• Bulk flammable liquid storage tanks.
• Structures supporting hazardous plant.
• Equipment such as conveyors.

In addition, Fire Prevention may be achieved particularly where flammable gas leaks are likely to occur. The action of the spray on the leak will help to dissipate the gas more quickly and prevent concentrations from reaching their flammable limits.

High Velocity (HV) systems are mainly used to extinguish fires involving oils or similar combustible liquids. Oil-filled electrical equipment such as transformers, or lubrication systems on steam-driven turbines are generally protected by HV systems.

Extinguishment of fires by HV’s is achieved by a combination of the following:

• Cooling of the burning oil surface reduces the vaporisation rate, and steam generated in the fire zone causes a smothering effect through oxygen displacement.
• Dilution of the burning product when water miscible product (eg: alcohol) can be diluted to a level where it will no longer burn.
• Emulsification through the bombardment of the surface of the product by the high-velocity water droplets. The emulsion formed consists either of globules of oil suspended in water or globules of water suspended in oil. The effect is temporary and the mixture will separate again in time.

Manual Fire Hydrants are very effective extinguishing systems suitable for various plants and high-rise buildings as well as commercial complexes.

The system mainly consists of a water storage reservoir (underground or aboveground), pump set, piping ring around the building, terminals inside the building, hydrant valves, hoses, branch pipes with nozzles, and hose boxes. On the ring main the hydrant stand posts are provided with hydrant valves.

Fire Hose Reel Systems consist of pumps, pipes, water supply and hose reels located strategically in a building, ensuring proper coverage of water to combat a fire. The system is manually operated and activated by opening a valve enabling the water to flow into the hose that is typically 30 meters away. The system pressure loss will activate the pump ensuring adequate water flow and pressure to provide a water jet of typically a minimum of 10 meters from the nozzle.

The automatic inductor on the suction side of the pump maintains the appropriate foam liquid quantity in the water stream. Water pressure of foam liquid suction ports are provided at the side of the automatic foam inductor unit. Water under pressure from the discharge side of the pump enters the pressure port inducing foam liquid from the tank through the foam liquid suction port.

A Fire Pump is a part of a Fire Sprinkler System’s water supply and powered by electric, diesel or steam. The pump intake is either connected to the public underground water supply piping, or a static water source (e.g., tank, reservoir, lake). The pump provides water flow at a higher pressure to the sprinkler system risers and hose standpipes.