Fire-demand empiricism: If P is the city population in thousands and Q is the fire demand in litres per minute, the commonly used empirical relation of this type is attributed to which author/agency?

Introduction / Context:
Designers use several empirical fire-demand formulae relating population to required fire flow (Q). Recognizing the names and general forms helps in quick exam recall and preliminary sizing before detailed risk assessments.

Given Data / Assumptions:

• P in thousands; Q in L/min.
• Classic formulas widely cited in water-supply textbooks.

Concept / Approach:

Kuichling’s formula is a well-known relation of the requested form, often expressed as Q = 4637 * sqrt(P) * (1 − 0.01 * sqrt(P)) (units may vary by text). Other names (e.g., Freeman, NBFU/ISO) exist but differ in structure or parameterization.

Step-by-Step Solution:

Verification / Alternative check:

Most standard Indian and international references list Kuichling among the canonical fire-demand relations alongside Freeman and NBFU/ISO adjustments.

Why Other Options Are Wrong:

• NBFU and Freeman have other recognised forms; the question pattern typically matches Kuichling.
• “None of these” is incorrect since Kuichling fits.
• “Babylon formula” is not a recognized engineering relation.

Common Pitfalls:

• Mixing coefficients and units across different textbook versions.

Final Answer:

Kuichling.