You've probably seen a movie or TV show where the overhead sprinklers go off in a building, dousing everybody inside.
Firefighters in Fargo are crediting one of those systems with stopping a fire from spreading at a local mall.
Around 2:42 a.m. on Sunday, the Fargo Fire Department got a call about a fire at Macy's in the West Acres Mall, a news release said. When firefighters arrived, they discovered a sprinkler head in one of the management offices had already extinguished the flames.
The department says the sprinkler system minimized what likely would have been "significant fire damage" to the department store.
"This incident reinforces the value of sprinkler systems and their ability to contain or extinguish fires prior to firefighters arrival," the release says.
It was determined that an overheated electrical device started the fire, which then spread to nearby office furniture. The department says the extent of the damages is being assessed.
"The Fargo Fire Department would like to remind everyone to safely exit a building at the first notification of a fire alarm and always practice exit drills in your home," the department said in the release.
How do they work?
In movies it's always a tiny bit of smoke that sets off the overhead sprinklers in a building. In real life, the sprinklers are heat activated, HowStuffWorks says.
And only one sprinkler head goes off at a time. Otherwise the whole building could get drenched just because of a small fire in one room, which would cause more harm (in water damages) than good.
Watch a sprinkler work in slo-mo:
P.S. Remember to check your smoke detector?
Fire departments usually encourage people to change their smoke detector batteries when changing their clocks.
If you forgot to do that during daylight savings time, take a few minutes – it could save your life.
The Fargo Fire Department says there have been 1,752 home fire fatalities in the U.S. so far this year.