Building Sprinkler Information, How does a sprinkler system work

Building sprinkler information speaks to how does a sprinkler system work to protect buildings from fire.

Wet Pipe Sprinkler Information

This automatic system circuit uses automatic wet pipe sprinklers attached to a piping system which contains water. It is connected to a water supply, enabling the water to discharge immediately from sprinkler heads released by a fire. The location of the main valve should be known by the operator.

The system may be at city water pressure or maintained about 25 psi above the city water pressure depending on how high the building is.This feature has been provided to reduce the frequency of nuisance false alarms, when there is a surge of pressure in the city lines.

To provide over pressure there is a small high pressure jockey pump connected from the city line side across the valve to the distribution system. A pair of pressure gauges are provided to show the pressure on each side of the valve.

To develop the pressure the jockey pump will energize automatically until there is a 25 psi differential pressure across the gauges.

As soon as system pressure drops off, the main fire pump will start to maintain water flow through the pipe system. The pump will run until manually turned off.

Once a system has been activated and no further fire hazard exists it is necessary to close the manual gate valve ahead of the valve.The heads that were released should be replaced and the main valve opened to make the system operational again.

Dry Type Sprinkler Information

The dry pipe fire sprinkler system uses sprinklers attached to a piping system, which may contain air or nitrogen under pressure. The escape of the air or nitrogen from the release of a head permits the water pressure to open a valve known as a dry pipe valve.

The water then flows into the piping system and out the opened heads. The building operator should know where the main valve is located.

Preaction Sprinkler Information

The preaction system employs automatic heads attached to a piping system containing low pressure air and uses a supplemental fire detection system. Actuation of the detection system opens a valve which permits water to flow into the piping system and discharge through any heads which may have opened.

The low air pressure in the piping system serves to activate a low pressure alarm if vandals should release any head.In the event the system has been activated, the piping must all be drained and new heads installed as required.

Deluge Sprinkler Information

The deluge system employs open sprinklers attached to a piping system, connected to a water supply through a valve, which is opened by a supplemental fire detection system.

It is located in the same area as the heads. When this valve opens, water flows into the piping system and discharges from all the heads. Complete water spray coverage is the result. The operator should know where the automatic valve is located.

In the event that the supplemental fire detection senses a fire condition, an alarm will sound but opening of the valve will be delayed for a preset time. This will allow the operator time to quickly assess the situation and abort the tripping of the valve, which would otherwise dump water in the area possibly causing unnecessary water damage.

Combined Dry Pipe and Preaction Automatic Sprinkler System Circuit

In the event of a fire alarm from the supplemental detectors in the area, an alarm condition is indicated on the alarm panel.Opening of the valve will be delayed for a preset period of time.

This gives the operator time to quickly assess the alarm condition and abort the opening of the valve if it happens to be a false alarm. If no action is taken during the delay, the valve opens along with the special air vent valves and the system goes into action, spraying water out of any heads that have released.

Antifreeze Automatic Sprinkler System Circuit

The antifreeze system uses automatic heads which are attached to a piping system containing an antifreeze solution and connected to a water supply. The antifreeze solution followed by water, discharges immediately when opened by a fire.

Building Fire Safety

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