1. What is a Fire Hose Flow Rate Calculator?

Definition: This calculator estimates the water flow rate from a fire hose nozzle based on the nozzle coefficient, diameter, and water pressure.

Purpose: It helps firefighters and emergency responders determine water flow rates for effective fire suppression.

2. How Does the Calculator Work?

The calculator uses the standard nozzle formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( c \) — Nozzle coefficient (typically 0.97 for smooth bore nozzles)
• \( d \) — Nozzle diameter (inches)
• \( P \) — Pressure (psi at the nozzle)

Explanation: The formula calculates flow by considering nozzle characteristics and the square root of pressure.

3. Importance of Flow Rate Calculation

Details: Proper flow rate estimation ensures adequate water supply for firefighting, proper nozzle selection, and effective fire stream management.

4. Using the Calculator

Tips: Enter the nozzle coefficient (default 0.97), diameter in inches, and pressure in psi. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical nozzle coefficient?
A: Smooth bore nozzles typically have a coefficient of 0.97, while fog nozzles range from 0.75-0.95 depending on design.

Q2: How does diameter affect flow rate?
A: Flow rate increases with the square of the diameter - doubling the diameter quadruples the flow (at same pressure).

Q3: Why use square root of pressure?
A: The relationship between pressure and flow is not linear - higher pressure increases flow but at a decreasing rate.

Q4: What's a typical fire hose pressure?
A: Most fire hoses operate at 50-100 psi at the nozzle, with some high-pressure systems reaching 150 psi or more.

Q5: How accurate is this calculation?
A: Very accurate for smooth bore nozzles. For fog nozzles, actual flow may vary based on pattern adjustment.