AWWA Technical Standards and Specifications 3 — Questions and Answers
Question 1: AWWA C502 covers which type of fire protection appurtenance?
- Post indicator valves
- Dry-barrel fire hydrants (Correct answer)
- Wet-barrel fire hydrants
- Fire department connections
Correct answer: Dry-barrel fire hydrants
AWWA C502 establishes design and performance requirements for dry-barrel fire hydrants, which are the type used in climates subject to freezing.
Question 2: What is the purpose of the AWWA C153/A21.53 standard?
- Compact fittings for ductile iron and gray iron pipe (Correct answer)
- Large-diameter steel fittings
- PVC solvent-weld fittings
- Brass service fittings
Correct answer: Compact fittings for ductile iron and gray iron pipe
AWWA C153/A21.53 covers ductile-iron compact fittings that are shorter and lighter than full-body fittings, reducing installation space and cost.
Question 3: According to AWWA C200, what is the minimum yield strength required for steel pipe used in water transmission?
- 24,000 psi
- 30,000 psi (Correct answer)
- 36,000 psi
- 42,000 psi
Correct answer: 30,000 psi
AWWA C200 specifies a minimum yield strength of 30,000 psi for steel cylinder pipe used in water transmission and distribution.
Question 4: AWWA C510 provides requirements for which valve type commonly used to isolate water mains?
- Ball valves
- Butterfly valves
- Double-check valve assemblies (Correct answer)
- Double check detector assemblies
Correct answer: Double-check valve assemblies
AWWA C510 covers double-check valve assemblies (DCVA) used to prevent backflow and protect potable water supplies from contamination.
Question 5: Under AWWA C111/A21.11, what type of joint is specified for ductile iron pipe connections in buried service?
- Flanged joint
- Mechanical joint
- Push-on joint with rubber gasket (Correct answer)
- Welded joint
Correct answer: Push-on joint with rubber gasket
AWWA C111/A21.11 covers rubber-gasket joints for ductile iron pipe, where a push-on (bell-and-spigot) joint seals via compression of an elastomeric gasket.
Question 6: What minimum wall thickness design factor does AWWA M17 (the Fire Hydrant manual) recommend for hydrant barrels?
- 0.15 inches
- 0.25 inches (Correct answer)
- 0.38 inches
- 0.50 inches
Correct answer: 0.25 inches
AWWA M17 recommends a minimum barrel wall thickness of 0.25 inches for cast-iron or ductile-iron fire hydrant barrels to resist mechanical damage.
Question 7: AWWA C651 prescribes which minimum chlorine contact time (CT) method as an alternative to high-concentration disinfection of new mains?
- Tablet method using calcium hypochlorite (Correct answer)
- UV irradiation
- Ozonation
- Chlorine dioxide injection
Correct answer: Tablet method using calcium hypochlorite
AWWA C651 allows the tablet method, where calcium hypochlorite granules or tablets are placed in the pipe before filling to achieve the required CT for disinfection.
AWWA Technical Standards and Specifications 3
AWWA C502 covers which type of fire protection appurtenance?