When planning a sprinkler system installation, one of the first decisions the fire safety expert has to make is what type of sprinkler system to install to ensure efficient fire control and compliance with relevant safety regulations. The most common types of fire sprinkler systems are wet, dry, deluge, and preaction, each with its own unique characteristics and applications.

Let’s take a closer look at how these systems operate and the key differences between them.

4 Types of Sprinklers and Their Uses

The first recognized fire sprinkler system was invented back in 1812, and, since then, many new types of sprinkler systems have been created. Today, four types of fire sprinklers are used for most applications, although many more different types of fire sprinklers exist. The main differences between the four types of sprinklers are their method of activation and application.

1. Wet Pipe Sprinkler Systems

Wet pipe sprinklers are the most common type of sprinkler used for Toronto buildings. This type of sprinkler system is called “wet,” because the sprinkler piping is filled with water at all times. If the temperature within the sprinkler head reaches a certain temperature, the fusible link or glass bulb inside it breaks, releasing the water to flow out of the sprinkler head.

Common Uses of Wet Pipe Sprinklers

Wet pipe sprinklers are believed to be the most reliable and cost-effective sprinkler systems out there; therefore, they should be considered for most applications. However, such systems are not appropriate for spaces where there is a risk of temperatures dropping low enough for the water within the sprinkler pipes to freeze.

Pros of Wet Pipe Sprinkler Systems

• Wet pipe sprinklers provide a reliable and quick response in the event of fire.
• They are more affordable to install and maintain as compared to other systems.
• Wet pipe systems are the standard for most commercial, residential, and industrial applications.

Cons of Wet Pipe Sprinkler Systems

• Wet pipe sprinklers are not suitable for cold environments where temperatures drop below freezing.
• The immediate release of water can cause significant water damage to the property.
• Wet pipe sprinkler system installation requires extensive planning and infrastructure.

2. Dry Pipe Sprinkler Systems

Dry pipe sprinkler systems are similar to wet pipe ones, except the sprinkler pipe is not filled with water by default. Instead, the water is contained behind a dry pipe valve, typically some distance away from the sprinkler head.

Just like with a wet pipe system, as soon as the temperature at the sprinkler head reaches a certain point, the fusible link or glass bulb inside it breaks. However, the water does not become instantly available, because the pipe is not filled with water. Instead, air is released from the open sprinkler head, causing a pressure drop and, therefore, opening the dry pipe valve and releasing the water.

Common Uses of Dry Pipe Sprinklers

Dry pipe sprinkler systems are an excellent option for unconditioned spaces or areas where there is a risk of the pipe temperature dropping below the freezing point. However, for such a space, it is still critical to ensure that the portion of the building where the water comes in maintains the above-freezing temperature.

With dry pipe sprinklers, the water flow is delayed after the sprinkler head activation, thus limiting the size of the system. This means that they may not be suitable for larger buildings and areas.

Pros of Dry Pipe Sprinkler Systems

• Dry pipe sprinklers are ideal for cold environments, as the pipes are not filled with water and, therefore, cannot freeze.
• Since water is only released when the sprinkler head is activated, there’s less risk of water damage in non-fire areas.
• Water flow is delayed until the sprinkler head is triggered, which offers a more controlled response to fire.

Cons of Dry Pipe Sprinkler Systems

• A slight delay before water is released can lead to a slower response time compared to wet pipe systems.
• Dry pipe systems are more complex to install and maintain as compared to wet pipe systems.
• Due to their complexity, dry pipe sprinkler systems are generally more expensive to install and maintain than wet pipe systems.

3. Deluge Sprinkler Systems

With a deluge sprinkler system, all connected sprinkler heads are open, with no sensing element or glass bulb inside. Because all sprinkler heads are open, the sprinkler piping is filled with atmospheric pressure, with a mechanically-activated deluge valve enabling the pipes to fill with water. The deluge valve is activated by a signal from a fire alarm system consisting of smoke and heat detectors, – once the signal is received, all open sprinklers begin to distribute water.

Common Uses of Deluge Sprinklers

With deluge sprinkler systems, all sprinkler heads are open and activate at the same time, quickly distributing water over the entire area. As such, these systems are used in areas where there is a concern for a rapid-fire spread, including chemical storage, aircraft hangars, or refineries.

Pros of Deluge Sprinkler Systems

• Deluge sprinkler systems release a large amount of water at the same time, providing a rapid and effective response to large fires.
• These systems are ideal for high-hazard areas, where fast and extensive fire suppression is necessary.
• All sprinklers in the system activate at once, ensuring that the entire area is covered with water quickly.

Cons of Deluge Sprinkler Systems

• Because all sprinkler heads activate at once, there is a high probability of extensive water damage to the property.
• Deluge systems are relatively complex and require a special control system, making installation and maintenance more expensive.
• Deluge systems are overkill for many environments and are usually reserved for high-risk industrial settings.

4. Preaction Sprinkler Systems

A preaction sprinkler system is likely the most complicated type of sprinkler for firefighting. There are three different types of preaction systems, differentiated by the type of event (or events) that must happen before water is released into the system:

• Non-Interlock Preaction System: Water is released when either the detection devices or automatic sprinklers are activated.
• Single Interlock Preaction System: Water is released only when the detection devices are activated.
• Double Interlock Preaction System: Water is released only when both the detection devices and automatic sprinklers are activated simultaneously.

Common Uses of Preaction Pipe Sprinklers

Preaction sprinkler systems require specific conditions to activate. As such, they are frequently used in areas where preventing accidental water discharge is crucial, such as in sensitive environments like data centers or museums.

Pros of Preaction Sprinkler Systems

• Preaction systems require multiple events to trigger water release, thus reducing the likelihood of accidental discharge.
• When the sprinkler system is activated, water is released immediately, offering a fast and efficient fire suppression response.
• Preaction sprinkler systems offer a combination of dry and wet pipe system benefits, allowing for better control in specific applications.

Cons of Preaction Sprinkler Systems

• Preaction systems are significantly more complex and require more components than other systems, which makes installation and maintenance more expensive.
• The sprinkler system is activated after multiple events, which can slightly delay the fire suppression process compared to wet pipe systems.
• Preaction systems require regular testing and extensive maintenance to ensure all detection and control devices function properly.

Final Word

Without a doubt, each type of fire sprinkler system offers its own unique advantages and disadvantages. The type and size of the property in question, the type of fire hazards within the building, and the specifics of the building’s infrastructure will dictate the choice of the appropriate sprinkler system. At Fire Safety Solutions, we can recommend the right type of sprinkler for your property, as well as install and maintain the system on an ongoing basis. Get in touch with us today to learn more about our fire sprinkler services in Toronto.