Why do firefighters use chain saws to cut holes in the roof of a building that’s on fire?
This is called "vertical ventilation." There are two basic reasons for this practice. Dangerous superheated gases and dark smoke accumulate in a burning building. Unlike the movie versions of fires, it is impossible for firefighters to see in such an environment or for victims to survive. When a hole is cut in the roof, and the building is “vented,” the smoke and gases escape because heat and smoke rise. It increases the victim¹s chance for survival and makes it much safer and more efficient for the firefighters in the building to see and operate. It also reduces the possibilities of backdraft (explosion) and flashover.

Another reason for venting the roof is to see how far the fire has progressed. One of the fastest avenues through which fires spread is the attic. Heat and smoke rise into the attic where the fire can move quickly.

Firefighters may also go ahead of the fire on a roof and cut holes to access the attic to stop the fire from spreading through the attic.

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1. What do firefighters do while they are waiting for a fire or other emergency?
2. What schedule do firefighters work?
3. Why do fire engines and ambulances respond on emergency medical calls?
4. Why do fire trucks with full lights and sirens go through a red light at intersections and then, after they go through, they turn off their lights and slow down?
5. Why do firefighters use chain saws to cut holes in the roof of a building that’s on fire?
6. Does the Fire Department service fire extinguishers?
7. When an emergency vehicle is approaching that is displaying emergency lights and sirens, what should I do?
8. Why did I see another Fire Department’s fire engine in Gilroy?
9. Why do so many fire trucks respond to simple incidents?
10. Why do fire trucks respond to motor vehicle accidents?