Blog

How Do Fire Sprinkler Systems Work?

July 16, 2025|FSSTechnologies

Fire sprinkler systems work by detecting heat from fires and releasing water to extinguish them. Different components work together in various configurations to boost a structure’s fire and life safety measures. Learn how a fire sprinkler system works, what your options are, and why it’s a necessary investment for your business.

What are the main parts of a sprinkler system?

Fire sprinkler systems are regulated by codes and standards from the National Fire Protection Association (NFPA). The specific codes that dictate requirements for the installation and maintenance of sprinkler systems are NFPA 13 and NFPA 25. While there are several options for what a system can use, these are some of the main components included for fire sprinklers.

Pipes

Fire-rated piping is installed in ceilings, overhead, or in walls to carry water to sprinkler heads. They’re laid out per design standards to fully cover protected areas based on the hazard levels in a building. Pipes and their joints are usually made of metals or heat-resistant plastic to ensure the entire system can still function in an active blaze.

Sprinkler heads

A sprinkler head acts like a stopper for the water stored in a system’s pipes. The main component that detects a fire by heat is a glass bulb or a fusible link. Once that element breaks or melts, water is released from the sprinkler head and bounces off a deflector plate to disperse. Escutcheons, also called trim plates, fill the gaps around sprinkler heads and prevent smoke or heat from passing the heat-sensitive component.

These are the four most common types of sprinkler heads:

  1. Pendent sprinkler heads hang from the ceiling and spray water in a domed or coned pattern. These heads are traditionally visible and more commonly used in standard commercial spaces.
  2. Upright sprinkler heads point upward and are often used when obstructions or other building elements prevent them from hanging. These are standard in manufacturing and industrial facilities.
  3. Sidewall sprinkler heads are installed along walls and spray water toward the center of a space. These heads are used in areas that are smaller or do not have pipes overhead or in the ceiling.
  4. Concealed sprinkler heads are recessed in walls or ceilings. They’re covered by a protective plate that melts at temperatures lower than the sprinkler’s heat element, enabling the head to drop and activate.

Sprinkler risers

System risers

A fire sprinkler riser acts as a bridge to connect a system with a structure’s water supply. Risers are traditionally vertical pipes with valves and gauges that control and measure water flow and pressure. A fire sprinkler riser is often located in a dedicated room within a building to simplify maintenance and inspection processes.

What are the main styles of sprinkler systems?

NFPA 13 permits four types of sprinkler systems that each offer different benefits and drawbacks for various regions, industries, and price points. Depending on the needs of a structure, different types can be combined to provide optimal fire protection measures. Here’s more information on how each system works and where it’s commonly used.

1. Wet pipe

In a wet pipe layout, the entire system’s piping is filled with water constantly. If a sprinkler head’s heat detector activates, water will be released from that specific point and not from the other heads in that system. Wet pipe sprinkler systems are usually a more reliable, cost-effective option, but they’re best suited for regions and structures that won’t experience freezing temperatures.

2. Dry pipe

Dry and wet pipe systems are similar, but the main differentiator is the presence of water within the pipes. Dry pipe configurations use valves and pressurized air or nitrogen to keep water out of the system’s pipes. Once a sprinkler head is activated, the drop in pressure allows water to flow out of the system. These systems are best for structures and areas without temperature control, but they’re kept small to avoid flow delays.

Pre-action sprinkler system

3. Pre-action

A pre-action system is a more complicated setup that can be non-interlock, single interlock, or double interlock, each of which requires specific triggers to run. These systems depend on heat or smoke detectors in addition to sprinkler heads, so an activated or broken sprinkler may or may not cause water to flow. Pre-action systems are best suited for businesses that want to avoid excessive water damage.

4. Deluge

A deluge system mimics a pre-action system in that it needs a detector to run. Detectors are typically configured to work with a valve to keep the system from filling. The main difference is that deluge systems use nozzles or open sprinklers, so a triggered system will release water from every opening. These sprinkler systems are ideal for structures with high hazard levels, such as power plants or chemical manufacturers.

How do sprinklers work within a fire alarm system?

Depending on the type of fire sprinkler system that’s in place, fire alarm integrations can be beneficial for a building’s inhabitants and first responders. A comprehensive commercial fire system can ensure that sprinklers aren’t activated from accidental damage, depending on the types of systems in place. Additionally, a triggered sprinkler can set off the alarm and notify monitoring services to seek emergency assistance.

FSS Technologies has your all-in-one solution

Understanding your options for sprinkler systems, heads, and configurations empowers you to make informed safety decisions. At FSS Technologies, we offer end-to-end fire sprinkler services that cover design, installation, inspection, and everything in between. Our NICET-certified team of service technicians is here to support you every step of the way, ensuring you achieve and maintain compliance standards and safety priorities with confidence. Contact us today to learn more and schedule a free consultation.

Explore Our Other Blogs

FSS_DecBlog_OPT_SmartHomeAgingAdults_Hero

Smart Home Technology for Aging Adults

Alzheimer’s Awareness Around 75% of seniors want to stay in their homes as they age, according to the American Association of Retired Persons (AARP), even if they need day-to-day assistance or have ongoing health issues like early-stage Alzheimer’s or dementia. According to the Alzheimer’s Association, 5.8 million Americans are living with the disease, and by…

Continue reading
2019-06_FSSTechnologies_blog_video-doorbell-privacy_hero-min

Video Doorbell Privacy Issues

Video Doorbells In the News Video doorbells are one of the hottest home security tools on the market today. We agree. Once you have a video doorbell, you’ll probably wonder how you ever lived without it. Check out our blog on How a Video Doorbell Works to learn more. However, like any technology on the…

Continue reading
2020-01_FSSTechnologies_blogs_ring-hack_hero-min

The Risky Business of Ring’s Vulnerable Security

If you are like the rest of Americans, you have noticed that the Ring Security company has been in the news lately— and not for anything useful. Between security hacks and lawsuits, the company has landed itself in hot water. Surveillance Camera Hacks Homeowners have security cameras installed in their homes to give them peace…

Continue reading
fire-safety-kids-Hero

Fire Safety for Kids

Setting up fire alarm systems and fire monitoring are fundamental elements in your home’s fire safety plan. However, that is only the beginning. Educating your children on fire prevention, fire safety, and how to manage an emergency are vital in keeping your family safe. According to the American Red Cross, not only are children under five…

Continue reading
Hero-codes

7 NFPA Codes Every Business Should Know

Business owners have an enormous responsibility to ensure their employees and customers are protected from fire hazards. Companies in industries like manufacturing and property management each face unique challenges in preventing fires and meeting code requirements. The National Fire Protection Association (NFPA), one of the world’s leading experts in fire and life safety, has published…

Continue reading
Herofireinspecti-min

How to Prepare for a Fire Inspection

Updated May 2023 Most people learn how to react to fire alarms from a young age. The sharp, jarring noise of the sirens instantly notifies everyone within earshot of a possible emergency and the need to evacuate. These fire safety alarm systems are mandated worldwide and need regular inspections and maintenance to promote safety. As…

Continue reading
cctv-cameras-illegal-in-workplace-hero-min

Is the Use of CCTV Cameras in the Workplace Illegal?

Know the Law Business owners are responsible for the security and well-being of their employees and company property. Many companies use technology such as cameras, motion detectors, and other tools to keep an eye on their building or cash areas. Many new businesses and employees may be wondering: Are CCTV cameras illegal in the workplace? Let’s…

Continue reading
Hero-pots

POTS Phase-Out: Impact on Life Safety Systems

When businesses hear about the POTS line phase-out, they often think only of desk phones. In reality, traditional copper phone lines have supported a much wider range of building systems, including fire alarms, security systems, elevator phones, and more. As carriers continue moving away from copper infrastructure, those connections may become more expensive, less reliable,…

Continue reading
convential-vs-addressable_fire-alarms-hero

Addressable vs. Conventional Fire Alarms

When determining what type of fire alarm systems are best for your business, it boils down to your choice between a conventional and addressable alarm system. The combination of smoke, heat, and carbon monoxide detectors work together with your control panel to keep your business safe. Additionally, you will need to determine what kind of automatic…

Continue reading
workplace-fire-procedures-hero-min

Fire Safety Procedures for the Workplace

The bad news—a fire breaks out in your workplace. The good news—you are ready because you have done your homework and prepared for the possibility of an emergency. Emergency Action Plan The Occupational Safety and Health Administration (OSHA) requires most employers to have an emergency action plan for various scenarios, including fires in the workplace. There are…

Continue reading
24h emergency
Secure My Space