Master Plumber Water Supply and Distribution Questions and Answers

Question 1

A new potable water system has been installed in a commercial building. According to the IPC, which of the following is an acceptable method for disinfection before the system is put into service?

Accepted Answer

Filling the system with a solution containing at least 50 ppm of chlorine and letting it stand for 24 hours.

Answer

Flushing the system with hot water at 140°F for at least 30 minutes.

Answer

Filling the system with a solution containing at least 25 ppm of chlorine and letting it stand for 12 hours.

Answer

Flushing the system thoroughly with clean, potable water until all visible debris is removed.

Question 2

A master plumber is designing a water supply system for a multi-story building. The static pressure from the municipal water main is 95 psi. What is required on the water service pipe near its entrance to the building?

Accepted Answer

A pressure-reducing valve (PRV)

Answer

A water hammer arrestor

Answer

A thermal expansion tank

Answer

A backflow preventer

Question 3

In a residential hot water supply system, a check valve has been installed on the main water service, creating a closed system. Which of the following is required to mitigate the effects of thermal expansion?

Accepted Answer

An approved and adequately sized expansion tank.

Answer

An additional pressure relief valve set at 100 psi.

Answer

A larger diameter cold water supply pipe to the water heater.

Answer

A circulation pump installed on the hot water line.

Question 4

A master plumber needs to determine the required size for a water service pipe for a new office building. The calculation involves determining the total water supply fixture units (WSFU), the developed length of the piping, and pressure losses. What additional piece of information is critical for this calculation?

Accepted Answer

The available static water pressure at the source.

Answer

The type of insulation on the hot water pipes.

Answer

The number of floors in the building.

Answer

The average daily temperature of the supply water.

Question 5

Which of the following scenarios explicitly requires the installation of a water hammer arrestor according to the IPC?

Accepted Answer

On the water supply lines to fixtures with quick-closing valves.

Answer

On any water supply line exceeding 100 feet in developed length.

Answer

At the base of every water supply riser in a multi-story building.

Answer

Immediately downstream of the main water meter for the building.

Question 6

When calculating the total pressure loss in a water distribution system, a master plumber accounts for losses from pipe friction, elevation changes, and the water meter. What other significant source of pressure loss must be included for an accurate design?

Accepted Answer

Pressure loss through fittings and valves.

Answer

The velocity of the water in the public main.

Answer

The ambient temperature surrounding the pipes.

Answer

The age of the municipal water supply infrastructure.

A new potable water system has been installed in a commercial building.According to the IPC, which of the following is an acceptable method for disinfection before the system is put into service?

A new potable water system has been installed in a commercial building.
According to the IPC, which of the following is an acceptable method for disinfection before the system is put into service?