What Is the NFPA 13 Fire Sprinkler Flow Rate (K-Factor) Calculator?
The sprinkler K-factor is a discharge coefficient relating water flow through a sprinkler nozzle orifice to the square root of pressure.
How Does the NFPA 13 Fire Sprinkler Flow Rate (K-Factor) Calculator Work?
Evaluates Q = K · √P in US customary units.
Converts flow rate to liters per minute.
NFPA 13 Fire Sprinkler Flow Rate (K-Factor) Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
Q = K · √P (gpm), Q_metric = 14.4 · K · √P_bar (L/min)
Standard Torricelli orifice discharge equation adapted for fire protection engineering.
How to Use the NFPA 13 Fire Sprinkler Flow Rate (K-Factor) Calculator
- Input manufacturer nominal K-factor.
- Specify operating residual pressure in psi.
Step-by-Step Example Calculation
Standard Commercial Sprinkler Head
Input Values:
kFactor:5.6
pressure:25
Worked Steps: K-5.6 head operating at 25 psi yielding 28 gpm.
Understanding Your Result
Primary output indicates flow rate in gpm and L/min.
Summary displays equivalent pressure in bar.
Factors That Affect the Result
- Piping friction losses and elevation changes.
When Should You Use This Calculator?
- Hydraulic calculations for commercial, residential, and warehouse fire sprinkler networks.
Assumptions & Limitations
- Minimum operating pressure of 7 psi required for proper droplet distribution pattern.
Frequently Asked Questions
Calculation Accuracy & Reference Note
NFPA 13 standard equation.