How Fire Sprinkler Systems Work

Fire sprinkler systems are triggered by extreme heat and can quickly extinguish a fire in the room where it started.
Fire sprinkler systems are triggered by extreme heat and can quickly extinguish a fire in the room where it started.
© Larsen

You've probably seen a number of movies where a small amount of smoke triggers all of the sprinklers in a building, soaking everyone and everything inside. But did you know that sprinklers aren't even triggered by smoke, and they don't all go off at once? Fire sprinkler systems are actually heat activated, one sprinkler head at a time, and most fires usually require only one or two sprinklers to be extinguished. These are just two of the many misconceptions about fire sprinkler systems. In this article, we'll dispel other myths and learn the ins and outs of this important safety technology.

You might think installing a fire sprinkler system is like choosing water damage over fire damage. This belief is a spinoff from the myths we just mentioned -- that sprinklers are activated by smoke and every sprinkler head goes off at the same time. If that were the case, sprinkler systems could potentially cause more harm than good. After all, if you burned a piece of toast, every sprinkler would go off, soaking all of your belongings, even though there never was any real danger of fire. Fortunately, the clever engineers who developed these systems designed them to reduce the damage to your property from water, smoke and fire.

Fire sprinkler systems have been around for more than two centuries and have seen significant improvements over the years. It's true that early versions weren't very reliable and caused significant water damage. But today, sprinkler systems are credited with reducing deaths and loss of property by more than 65 percent [source: Fleming]. Since each sprinkler head is automatically triggered by fire-specific temperature, just one or two sprinklers can quickly extinguish and/or contain a fire to the room where it started and cause little property damage. And because sprinklers use about six times less water than a fire hose, they're actually less harmful to your property than a visit from the fire department.

Still convinced you know everything you need to know about fire sprinklers? We'll address another common myth and discuss the details of how sprinklers work on the next page.