CPD Plumbing Systems Design 2

Question 1

According to the IPC, what is the minimum slope required for a 3-inch horizontal drain pipe?

Accepted Answer

1/4 inch per foot

Answer

The IPC requires horizontal drain pipes 3 inches and smaller to slope at a minimum of 1/4 inch per foot toward the point of discharge.

Question 2

Which type of water heater arrangement provides the highest first-hour delivery rating?

Accepted Answer

Multiple tank series arrangement

Answer

Multiple tanks connected in series maximize first-hour delivery rating because successive tanks pre-heat water and increase total storage volume.

Question 3

In a sanitary drainage system, what is the purpose of a cleanout installed at the base of a stack?

Accepted Answer

To allow rodding access to clear horizontal drain blockages

Answer

A cleanout at the stack base allows maintenance personnel to rod out the horizontal building drain without dismantling pipe connections.

Question 4

What minimum air gap is required between a potable water supply outlet and the flood level rim of a lavatory under ASSE 1012 standards?

Accepted Answer

2 times the supply pipe diameter

Answer

ASSE 1012 and most plumbing codes require an air gap of at least twice the supply pipe diameter between the outlet and the flood level rim to prevent backflow.

Question 5

A designer is sizing a medical gas oxygen system. Which document is the primary standard governing the design?

Accepted Answer

NFPA 99

Answer

NFPA 99, Health Care Facilities Code, is the primary standard governing the design, installation, and testing of medical gas and vacuum piping systems.

(CPD) Certified Plumbing Designer Practice Test

(CPD) Certified Plumbing Designer Practice Test

CPD Plumbing Systems Design 2