CFPS Water-Based Suppression Systems 3

Question 1

In hydraulic calculations for sprinkler systems, what does the Hazen-Williams formula calculate?

Accepted Answer

Friction loss per foot of pipe

Answer

The Hazen-Williams formula (p = 4.52 × Q^1.85 / (C^1.85 × d^4.87)) calculates friction loss per unit length of pipe based on flow, diameter, and pipe material coefficient.

Question 2

A sprinkler has a K-factor of 5.6 and is discharging at 25 psi. What is the approximate flow rate using Q = K × √P?

Accepted Answer

28 gpm

Answer

Using Q = K × √P: 5.6 × √25 = 5.6 × 5 = 28 gpm — the fundamental sprinkler discharge formula.

Question 3

What is the Hazen-Williams C-factor assigned to new black steel (Schedule 40) pipe per NFPA 13?

Accepted Answer

120

Answer

NFPA 13 assigns a Hazen-Williams C-factor of 120 to new black steel pipe, reflecting its moderate interior smoothness.

Question 4

In a hydraulically designed sprinkler system, what does the term 'remote area' refer to?

Accepted Answer

The hydraulically most demanding zone that must receive the full design density

Answer

The remote area is the hydraulically most demanding design area; proving adequate density there confirms the entire system is adequately supplied.

Question 5

Per NFPA 15, water spray fixed systems are designed to provide:

Accepted Answer

Both direct fire suppression on specific hazards and exposure protection of adjacent equipment or structures

Answer

NFPA 15 water spray systems serve dual roles: suppressing fires on specific hazard targets and protecting adjacent equipment or structures from heat exposure.

CFPS (Certfied Fire Protection Specialist) Practice Test

CFPS (Certfied Fire Protection Specialist) Practice Test

CFPS Water-Based Suppression Systems 3