CPD Sanitary Drainage Systems 3

Question 1

A stack serving more than 10 branch intervals must be provided with a:

Accepted Answer

Yoke vent at every fifth interval

Answer

The IPC requires yoke vents (relief vents) at every fifth interval when a drainage stack serves more than 10 branch intervals to relieve pressure fluctuations.

Question 2

Which material is generally NOT approved for underground sanitary drain piping inside a building per the IPC?

Accepted Answer

Threaded galvanized steel

Answer

Threaded galvanized steel is not approved for underground sanitary drainage because it corrodes rapidly when buried and exposed to wastewater.

Question 3

In sanitary drainage design, what is a 'branch interval'?

Accepted Answer

A vertical measurement of at least 8 feet along a drainage stack

Answer

A branch interval is a vertical measurement of not less than 8 feet within a stack, representing the space between horizontal branch connections.

Question 4

Which of the following scenarios requires an indirect waste connection rather than a direct drain connection?

Accepted Answer

A commercial dishwasher in a restaurant kitchen

Answer

Commercial dishwashers must discharge through an indirect waste connection with an air gap to prevent contamination of the potable or sanitary system by backflow.

Question 5

When a sanitary drain must pass under a footing, the minimum clearance between the top of the pipe and the bottom of the footing is:

Accepted Answer

No clearance required if pipe is in a sleeve

Answer

When a pipe passes under a footing, IPC allows it if properly sleeved or protected such that the footing load is not transferred to the pipe.

(CPD) Certified Plumbing Designer Practice Test

(CPD) Certified Plumbing Designer Practice Test

CPD Sanitary Drainage Systems 3