Quantity of Water given Duration of Fire Calculator

Water Quantity Formula:

\[ Q_w = \frac{4360 \times \left(\frac{T}{31556952}\right)^{0.275}}{\left(\frac{td}{60} + 12\right)^{0.757}} \]

Water Quantity (L/min):

Variation Range (±5%):

1. What is Quantity of Water given Duration of Fire?

Definition: This calculator estimates the quantity of water required to extinguish a fire based on the time period of fire occurrence and its duration.

Purpose: It helps fire safety professionals and emergency responders determine the water discharge rate needed for fire suppression.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q_w = \frac{4360 \times \left(\frac{T}{31556952}\right)^{0.275}}{\left(\frac{td}{60} + 12\right)^{0.757}} \]

Where:

\( Q_w \) — Quantity of water (liters per minute)
\( T \) — Time period of fire occurrence (seconds)
\( td \) — Time duration of fire (seconds)

Explanation: The formula calculates water discharge rate based on empirical relationships between fire occurrence time and duration.

3. Importance of Water Quantity Calculation

Details: Accurate water quantity estimation ensures effective fire suppression, proper resource allocation, and safety during firefighting operations.

4. Using the Calculator

Tips: Enter the time period and duration in seconds, and the variation percentage (default ±5%). All time values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What does the variation percentage mean?
A: The ±% range accounts for real-world variations in fire conditions and water application effectiveness.

Q2: Why is the time period in seconds?
A: The formula uses seconds for precise calculations, but you can convert from minutes (×60) or hours (×3600).

Q3: What's the significance of 31556952 in the formula?
A: This represents the number of seconds in a year (365.2422 days), used to normalize the time period.

Q4: When would I adjust the variation percentage?
A: Increase variation for uncertain conditions or when dealing with highly flammable materials.

Q5: How accurate is this formula?
A: It provides a good estimate but should be supplemented with professional judgment and local fire codes.