Note:

The Fire Flow is the estimated amount of water required to control a fire in a building, measured in gallons per minute (GPM). It is based on the **Fairfax County Method (Modified ISO Method)** and considers construction type, floor area, occupancy reduction, exposure distance, and sprinkler protection.

Calculation Process:

The fire flow is calculated in **four steps**, ensuring proper application of limits:

1. Raw Fire Flow: Estimated using building type, total floor area, and exposure distance.
2. Max Fire Flow Limit: If the calculated fire flow exceeds **6000 GPM**, it is capped at **6000 GPM**.
3. Adjustments for Occupancy & Sprinklers: Fire flow is reduced based on occupancy and sprinkler factors.
4. Minimum Fire Flow Limit: The final fire flow must be at least **500 GPM**, even after reductions.

Explanation of Parameters:

• Total Floor Area (A): The total built-up area of the structure (excluding basements). A larger area increases fire hazard, requiring more water for suppression.
• Building Type (C): Determines the fire resistance of construction materials. - Noncombustible (Fire-Resistive) (0.6): Reinforced concrete, steel (lower fire flow). - Ordinary Construction (0.8): Brick or wood mix (moderate fire risk). - Wood Frame (1.0): Highly combustible, requiring maximum fire flow.
• Fire Sprinkler System Reduction: - **Fully Sprinklered (0.5):** Sprinklers significantly reduce fire flow needs. - **No Sprinklers (1.0):** Higher fire flow required due to increased risk.
• Occupancy Reduction (OR): - **Office Buildings (0.9):** Lower fire risk, reducing required fire flow. - **Industrial/Warehouse (0.85):** Moderate fire risk. - **High-Hazard Facilities (1.0):** No reduction, as they pose a greater risk.
• Exposure Distance (ED): Accounts for nearby structures that can increase fire spread. - **No Nearby Buildings (1.0):** No increase. - **One Nearby Building (1.15):** 15% increase in fire flow. - **Two Nearby Buildings (1.3):** 30% increase in fire flow.

Why Fire Flow is Important?

• Fire Suppression: Ensures enough water to control fire spread.
• Structural Protection: Prevents excessive building damage.
• Code Compliance: Meets fire safety regulations and insurance requirements.
• Emergency Planning: Helps fire departments determine hydrant and water supply needs.

Enter the details and click "Calculate Fire Flow" to estimate the required water supply for your building.