CFPS Water-Based Suppression Systems 2 — Questions and Answers
Question 1: Per NFPA 13, what is the maximum allowable coverage area per sprinkler head in an Ordinary Hazard occupancy?
- 100 sq ft
- 130 sq ft (Correct answer)
- 168 sq ft
- 225 sq ft
Correct answer: 130 sq ft
NFPA 13 limits Ordinary Hazard occupancy sprinkler coverage to 130 sq ft per head due to the higher fire potential compared to Light Hazard.
Question 2: What is the primary function of a water motor gong (mechanical alarm) on a wet pipe sprinkler system?
- Boost water pressure to remote sprinklers
- Provide a local audible alarm driven by water flow through the alarm valve (Correct answer)
- Automatically notify the fire department dispatch center
- Control the main system shutoff valve position
Correct answer: Provide a local audible alarm driven by water flow through the alarm valve
A water motor gong is driven by water flowing through a restricted orifice at the alarm valve, producing a loud local audible alarm without electricity.
Question 3: Which NFPA standard governs the installation of standpipe and hose systems?
- NFPA 13
- NFPA 14 (Correct answer)
- NFPA 15
- NFPA 25
Correct answer: NFPA 14
NFPA 14, Standard for the Installation of Standpipe and Hose Systems, covers design, installation, and maintenance requirements for these systems.
Question 4: Per NFPA 20, what performance criterion must a listed fire pump meet at churn (no-flow, shutoff) condition?
- Pressure must equal exactly 100% of rated pressure
- Pressure must not exceed 140% of rated pressure (Correct answer)
- Pump must deliver 150% of rated flow capacity
- Pressure must be at least 65% of rated pressure
Correct answer: Pressure must not exceed 140% of rated pressure
NFPA 20 requires that a fire pump's pressure at churn (shutoff) shall not exceed 140% of its rated pressure to prevent overpressurizing the system.
Question 5: What substance fills the distribution piping between the dry pipe valve and the sprinkler heads in a dry pipe system under normal (standby) conditions?
- Pressurized air or nitrogen (Correct answer)
- Antifreeze solution
- Foam concentrate pre-mix
- Inert gas at atmospheric pressure
Correct answer: Pressurized air or nitrogen
Dry pipe systems maintain pressurized air or nitrogen in the distribution piping to hold the dry pipe valve clapper closed until a sprinkler head opens.
Question 6: Which sprinkler system type is most appropriate for an unheated walk-in cold storage freezer room?
- Wet pipe system
- Dry pipe system (Correct answer)
- Pre-action (single interlock) system
- Deluge system
Correct answer: Dry pipe system
Dry pipe systems are used where piping may be subject to freezing because the distribution piping contains pressurized air, not water, during standby.
Question 7: Per NFPA 13, what is the minimum residual pressure required at the hydraulically most remote sprinkler during system discharge?
- 7 psi (Correct answer)
- 15 psi
- 20 psi
- 25 psi
Correct answer: 7 psi
NFPA 13 requires a minimum of 7 psi at the most remote sprinkler to ensure adequate water distribution from the deflector.
CFPS Water-Based Suppression Systems 2
Per NFPA 13, what is the maximum allowable coverage area per sprinkler head in an Ordinary Hazard occupancy?