F80 Water Supply and Fire Suppression 5 — Questions and Answers
Question 1: What color are fire hydrant barrels typically painted to indicate they are privately owned and maintained?
- Red (Correct answer)
- Yellow
- Green
- Purple
Correct answer: Red
Red hydrant barrels typically indicate private ownership, though color coding can vary by jurisdiction; always verify local standards.
Question 2: A fire pump is sized to deliver 750 GPM at 100 psi. At churn (no-flow) condition, the pump discharge pressure should not exceed:
- 110% of rated pressure
- 115% of rated pressure
- 120% of rated pressure
- 140% of rated pressure (Correct answer)
Correct answer: 140% of rated pressure
NFPA 20 requires that at churn (shutoff) conditions, the pump pressure shall not exceed 140% of the rated net pressure.
Question 3: What is the function of a jockey (pressure maintenance) pump in a fire suppression system?
- Provide emergency backup to the main fire pump
- Maintain system pressure and detect small leaks (Correct answer)
- Boost pressure during a major fire event
- Prime the main fire pump before startup
Correct answer: Maintain system pressure and detect small leaks
A jockey pump maintains baseline system pressure and cycles to compensate for minor leaks, signaling potential problems if it runs excessively.
Question 4: Which NFPA standard governs the installation of private fire service mains and their appurtenances?
- NFPA 13
- NFPA 14
- NFPA 20
- NFPA 24 (Correct answer)
Correct answer: NFPA 24
NFPA 24 covers the installation of private fire service mains and their appurtenances, including underground piping.
Question 5: When conducting a fire hydrant flow test, the 'pitot pressure' reading is used to determine:
- Static pressure in the main
- Residual pressure during flow
- Velocity pressure and calculate flow rate (Correct answer)
- Pipe friction loss
Correct answer: Velocity pressure and calculate flow rate
A pitot gauge measures velocity pressure at the hydrant discharge opening, which is converted to flow rate (GPM) using standard formulas.
Question 6: In a Class III standpipe system, the hose connections are designed for use by:
- Fire department only
- Building occupants only
- Both fire department and trained building occupants (Correct answer)
- Automatic sprinkler systems only
Correct answer: Both fire department and trained building occupants
Class III standpipe systems include both 2½-inch fire department connections and 1½-inch hose stations for trained occupants.
Question 7: What pipe material is commonly prohibited for use in underground fire service mains due to its susceptibility to corrosion in certain soil conditions?
- Ductile iron
- HDPE (High-Density Polyethylene)
- Unlined cast iron (Correct answer)
- PVC Schedule 40
Correct answer: Unlined cast iron
Unlined cast iron is susceptible to internal and external corrosion and is generally no longer permitted for new underground fire service main installations.
F80 Water Supply and Fire Suppression 5
What color are fire hydrant barrels typically painted to indicate they are privately owned and maintained?