A Beginner’s Guide to Fire Sprinkler Systems

Fires start and spread in unpredictable ways, potentially blazing out of control within minutes of when they start. Flames and smoke enter walls, ceilings, vents, and stairwells, causing significant damage and causalities. Fire sprinkler systems are designed to save lives and property, extinguishing a fire or keeping it under control long enough for firefighters to arrive. They’re a critical component of any fire safety protection program, yet many people are unclear on why they’re needed or how they work.

Here’s everything you need to know about commercial fire sprinkler systems, including the different types, how they function, and why they’re essential to proper building maintenance and employee safety.

Types of Commercial Fire Sprinklers

The National Fire Protection Association permits four types of fire sprinkler systems for commercial use: wet, dry, preaction, and deluge.

1. Wet pipe sprinkler systems are the most common type and are also considered the most reliable and cost-effective. In these systems, the system’s piping is constantly filled with water. When the temperature at the ceiling reaches a certain point, a glass bulb or fusible link in a sprinkler head breaks, releasing water onto the flames. Wet systems should not be used in areas where it’s possible that the water in the pipes could freeze.
2. Dry pipe systems are not constantly filled with water. Instead, the water is held behind a dry pipe valve typically located some distance from the sprinklers. This setup causes a slight delay between sprinkler operation and water flow. To speed up water delivery, the size of a dry pipe system is limited.
3. Preaction systems are generally the most complicated sprinkler systems. The three types of preaction systems are non-interlock, single interlock, and double interlock. They differ from wet and dry pipe systems in that water is not released into the system until a specific event occurs, such as the temperature rising to a certain degree.
4. Deluge systems are similar to preaction systems, also using another type of detection for operation. However, deluge systems use open sprinklers or nozzles, so water flows from every sprinkler head instead of individual heads.

How Commercial Fire Sprinkler Systems Work

Commercial fire sprinklers are not triggered by smoke; rather, they’re activated by excessive heat, typically anywhere from 155 to 165 degrees Fahrenheit. Most systems contain glass bulbs that have a heat-sensitive liquid. When the system detects temperatures consistent with fire-like conditions, the liquid expands and breaks the glass bulb, activating the fire sprinkler system.

It’s important to remember that commercial fire sprinkler systems are designed to extinguish or contain fires and minimize the extent of property damage. Though mishaps are relatively uncommon, they can be accidentally activated, either through tampering or normal wear and tear.

Selecting the Correct Fire Sprinkler System for Your Building

Each type of fire sprinkler system has its own benefits. When choosing a system for your building, consider the pros and cons of each type for your specific environment. Some buildings or facilities might do best with a combination of systems. For instance, a common sprinkler design in the Northeast is one where a wet pipe system is used in protected building areas, and a dry pipe system is installed in unconditioned locations.

When you work with Firetech’s sprinkler design team, you’ll benefit from a system that provides optimal fire protection for your New York, Vermont, or New Hampshire building or commercial complex.

Still have questions about fire sprinkler systems and which one is right for you? Contact us today at 802-655-1800 to learn more.