Sprinkler systems are important in fire protection strategies in many buildings. Although they have common functions to keep the fire under control until the appropriate authorities arrive at the scene, sprinkler systems operate differently. In general, there are four types, viz. deluge system, wet tube, pre-action and dry tube. We will elaborate more on the differences below. Our main focus is on one of the most popular sprinkler systems: fire preaction sprinkler system.
The pre-action sprinkler system is predominantly used in water-sensitive environments such as data centers and museums, which can be damaged by water if an inadvertent discharge occurs due to false alarms. Other sprinkler systems are prone to accidental discharges and such discharges can cause massive damage to delicate items.
Protect your building from fires with a well-designed automatic sprinkler system.
What is a preaction sprinkler system?
A pre-action sprinkler system is basically a hybrid between different sprinkler systems, particularly wet and dry pipe systems. But it predominantly utilizes the dry pipe sprinkler system concept, where water is not readily available in the piping system until triggered by smoke or heat sensors. What distinguishes the preaction system from the dry pipe system is the supplementary sensing of the electrically controlled preaction valve. In short, the pre-action system has additional security against inadvertent discharges, whereas the dry pipe may be subject to accidental discharges.
This system is ideally available in two versions: double interlocking and single interlocking. With the single interlock system, the valve must be activated to release water into the pipes, and then the sprinklers must also be activated by heat to release the water. The double interlock system, on the other hand, uses air or nitrogen inserted into the piping system to help monitor possible leaks and help keep the water intact if the valve fails so there is no accidental discharge. It is evident that double interlocking offers extra security and as such is preferred even if installation becomes challenging.
Advantages of pre-action fire extinguishing system
- Best suited for water-sensitive environments such as data centers, archival vaults and laboratories
- Double action to discharge water thus ensuring there are no accidental releases of water
- Prevents water damage and fire damage
- Ideal for extremely cold areas because water does not freeze in pipes as it is not easily trapped in the piping system unless the valve is activated.
Disadvantages of pre-action sprinkler system
- It is challenging and expensive to install pre-action sprinkler systems because they require many components, such as supplemental detection devices.
- Regular maintenance required
- Difficult to modify the system as is the case with dry pipe systems due to size limitations
- There is a waiting time before the water is discharged
Pre-Action Sprinkler System Versus Other Sprinklers
As highlighted at the beginning, pre-action sprinklers are part of a sprinkler family that includes wet-pipe, deluge, and dry-pipe systems. All of these sprinklers have a common function and that is to extinguish flames before a fire gets out of control in buildings. Choosing a specific sprinkler depends on several purposes, such as the type of items stored and the urgency of the response. For example, deluge sprinkler heads are always open, so they react as quickly as a wet pipe system. On the other hand, pre-action and dry pipe sprinkler systems have a delay. Let’s elaborate more on their differences below:
Wet pipe fire sprinkler systems: water is stored directly in the pipes, ready to be discharged if the sprinkler is activated when a fire occurs. There is no delay with this system; it discharges water instantly, thus minimizing the likelihood of fire damage.
Dry Pipe Sprinkler Systems: In environments notorious for extremely cold temperatures, wet pipe systems would possibly freeze and therefore render the system useless in fire emergencies. The dry pipe sprinkler system works best in cold climates because water is not stored directly in the pipes until activated. The tube can be filled with air or nitrogen gas which is released when the heat activated sprinkler opens. The pressure in the pipe will decrease, causing the valve to open to discharge the water.
Deluge sprinkler systems: These are not popular, or rather applicable, in residential properties due to the nature of their operation. The sprinkler is always open and is not activated by heat sensors. There is a valve controlled by a specialized alarm to open and discharge water in large volumes until the valve is manually turned off. Deluge sprinkler systems are best suited for environments where fire emergencies may be frequent. Unlike residential sprinklers, these require manual operation to turn off the valve after a discharge.
Pre-action sprinkler systems: There is not much to say about these systems as we have already highlighted them above. The main advantage of these systems is that they are not subject to false alarms and inadvertent discharges, preventing possible water damage due to accidental discharges without fire.
Installation of pre-action fire extinguishing systems in buildings
To install these systems, you need a pipe network with a reliable water supply for your installation. The entire setup can be complex as this system is demanding compared to others. Installation requires advanced sprinkler engineering experience . New York engineers have extensive experience and knowledge to design, install and maintain pre-action fire sprinkler systems.
Building codes reinforce the importance of having sprinkler systems in buildings as the best measures to manage possible fire emergencies. Installing fire preaction sprinklers in water-sensitive areas is more mandatory than optional, as other sprinkler systems are prone to accidental discharges.
Wrap up!
For water-sensitive areas, pre-action sprinkler systems are essential due to their extended safety and dual function. Common areas for these systems are museums, archival vaults, data centers, and any other area where water damage could be catastrophic. Pre-action sprinklers are also best applied in cold climates where wet piping systems would freeze because water is stored quickly and directly in the pipes.
