Fire sprinkler systems

Wet Sprinkler System

These are the most common fire sprinklers and are installed to protect premises where there is no risk of freezing. The systems are permanently charged with water and as such the systems are very quick to react, as there is water permanently in the pipework above the sprinkler heads. Wet fire sprinkler systems are required for multi-storey or high rise and for life safety systems.

 

Alternate Sprinkler Systems

This type of sprinkler system is used in buildings where there is a chance of freezing during the winter months. The systems have pipes full of water during the summer and when the weather starts getting colder, they are drained down and filled with air under pressure for the winter. When there is a fire whilst the system is on air, the air pressure in the system drops on operation of a sprinkler head and water is then discharged from the system onto the fire.

 

Dry Pipe Sprinkler Systems

The pipework in the system is permanently filled with air under pressure and the system operates in the same way as the alternate system when on air. Dry pipe systems are used in buildings or parts of buildings where there is a permanent risk of freezing, such as chiller rooms and cold stores.

 

Pre-Action Sprinkler Systems

These types of systems are specifically designed for the protection of high value ‘business critical’ areas, such as computer rooms and server rooms to prevent discharge of the system due to accidental damage.
The systems are permanently charged with air which will drop and trigger a low air signal should a sprinkler head be accidentally broken. The system will only be charged with water once a signal has been received from two independent detection devices. These signals will cause an actuation valve to open and release water into the pipes. Activation of the system would then occur in the normal way of a sprinkler head being triggered by heat.