How Much Water is Used to Put Out a Fire?
How to Determine the Amount of Water Needed
Determining the amount of water needed is one of the most important factors in deciding how to fight a fire. So exactly how much water is needed to put out a fire? Of course, it’s going to depend on the size of the fire and the types of material that are burning.
In the event of a fire, the initial incident commander from the responding fire department is in charge of determining the amount of water needed. The National Fire Academy has developed a formula that allows for a quick calculation to help determine the amount of water needed. This formula takes the square footage of a burning structure and divides it by three.
Let’s Do the Math
For example, let’s say you’re a firefighter responding to a house on fire that is 60 feet long, 30 feet wide, and one story high. You would multiply 60 and 30 for a total of 1,800 square feet. Then, you’d divide 1,800 by three to determine that 600 gallons of water will be needed to fight that fire.
If this house had an additional story, you would double that number, meaning the fire would require 1,200 gallons of water.
However, this formula is intended to only give firefighters a starting point. There are other factors that need to be taken into consideration when determining how to effectively fight a fire. For example, the types of material burning and the type of fire hose being used also play a role in the equation.
The Role of Materials
Synthetic materials burn hotter and faster than natural materials. For example, a house with vinyl or fiber cement siding will deteriorate faster than a house with a wood or brick exterior.
Since synthetic building materials and furnishings are being used more and more in modern homes and buildings, these structures are more of a fire hazard. When they do catch fire, these fires can be harder to fight and require more water to get them under control.
The Role of Fire Equipment
Fire Hoses
There are various sizes of fire hoses, each with a specific purpose for fire suppression. For example, a 1.75-foot hose is what you typically see a firefighter using when they enter a burning structure or are working to extinguish an outdoor fire. This hose is known as an “attack” line and fire trucks are typically equipped with 500 feet of it.
Fire Trucks
There are several types of fire trucks that can transport various amounts of water, along with hoses, equipment, and of course, firefighters. Depending on the type of truck, these can hold anywhere from 500 to over 3,000 gallons of water. Engines that respond to structure fires can hold more water, while wildland firefighting trucks carry smaller amounts of water.
Rural areas where there are no fire hydrants do present a challenge for firefighters. That’s why fire engines are also equipped to draft water from nearby water sources, such as ponds, rivers, lakes, or even swimming pools.
Fire Hydrants
If fire hydrants are available to firefighters, these can pump out 1,000 gallons of water per minute from the city’s water supply. Easy access to fire hydrants make a firefighter’s job much easier, as they don’t have to locate and draft from another water source.
In Conclusion
No fixed amount of water will effectively control and put out a fire. It’s all going to depend on what’s burning and how much is burning.
The best answer to how much water is used to put out a fire is simply enough water for the given circumstance. Firefighters may need several hundred gallons of water or tens of thousands of gallons depending on the situation they’re responding to.
