To control a fire in a wooden storage building measuring 20ft x 40ft x 20ft high, what is the estimated flow rate of water needed?

• A. 80 gallons per minute
• B. 160 gallons per minute
• C. 200 gallons per minute
• D. 250 gallons per minute

Answer: (B)

To determine the estimated flow rate of water needed to control a fire in a wooden storage building, it's important to consider factors such as the size of the building, the materials involved, and the fire's potential intensity. The dimensions given (20ft x 40ft x 20ft high) suggest a significant volume of combustible materials, typical in wooden structures.

A common method for estimating water flow rate needed for firefighting is based on the volume of the structure and the potential fuel involved. The flow rate can be derived from industry standards that approximate the required gallons per minute to effectively suppress fires in unprotected wooden buildings.

The flow rate of 160 gallons per minute is reasonable for adequately controlling a fire in a smaller wooden structure. This figure accounts for the need to apply enough water to penetrate and cool down the combustion processes, while also ensuring that the fire does not have the opportunity to spread uncontrollably.

Using empirical data and firefighting guidelines, factors such as minimum water application rates – often considered to be around 0.10 gallons per square foot of area for Class A (ordinary combustibles) fires – support that 160 gallons per minute would not only suppress the flames but also allow enough cooling over time to prevent re-ignition.