Plumbing Systems Design Flashcards
7 cards from real CPD practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Plumbing Systems Design flashcards as text
Which standard governs the design and performance testing of thermostatic mixing valves used to limit domestic hot water delivery temperature?
Answer: ASSE 1017
ASSE 1017 covers thermostatic mixing valves for use on domestic hot water supply systems, establishing performance and temperature control requirements to prevent scalding.
A designer is routing a natural gas line under a concrete slab. Which type of gas piping is permitted for this concealed underground application per the International Fuel Gas Code?
Answer: Yellow polyethylene (PE) gas pipe
Yellow polyethylene (PE) gas pipe is specifically designed and code-approved for underground gas service and distribution piping; it resists corrosion and soil stress.
In designing a solar thermal domestic hot water system, what component prevents reverse thermosiphon flow from cooling stored water at night?
Answer: Check valve on collector supply line
A check valve installed on the collector supply line prevents reverse thermosiphon flow at night, when the collector is cooler than the storage tank and would otherwise drain heat back to the roof.
Under the IPC, what is the maximum number of water closets that a single 4-inch horizontal branch drain may serve?
Answer: 6
Per IPC Table 703.2, a 4-inch horizontal branch drain is permitted to serve a maximum of 6 water closets.
Which seismic bracing standard is referenced by the IPC and IAPMO for plumbing system restraint requirements in seismic design categories C through F?
Answer: ASCE 7
ASCE 7 (Minimum Design Loads and Associated Criteria for Buildings and Other Structures) establishes seismic design categories and the lateral force requirements that plumbing bracing must satisfy.
A designer is specifying a reduced-pressure detector assembly (RPDA) rather than a standard RPZ. What distinguishes an RPDA from a standard RPZ backflow preventer?
Answer: An RPDA includes a bypass line with a meter to detect unauthorized usage
An RPDA (reduced pressure detector assembly) incorporates a full-size RPZ for backflow protection and a small bypass line with a meter, allowing detection of unauthorized low-flow usage through the assembly.
When calculating developed pipe length for friction loss in a water distribution system, what percentage is typically added to the measured pipe length to account for fittings and valves?
Answer: 20%
A commonly used rule of thumb adds 20% to the measured pipe length to account for equivalent lengths of fittings and valves when performing friction loss calculations using the Hazen-Williams method.