Welcome to our basic plumbing practice test. Plumbing is a great career to choose since it’s one of the highest paying skilled trade careers.

General Knowledge Plumbing Practice Test

Similar questions may appear on your official exam but these are strictly for practice. Plus, they’re kind of fun.


You passed plumbing genius!

You did not pass but don’t fret, that’s what plumber training is for.

#1. What are the fresh water supply, sewage lines, and ventilation in new building construction commonly known as?

Just a little more studying will help!

#2. Where should water meters be installed?

Keep on studying, you’ll get it!

#3. The name of the fitting that allows a secondary pipe to branch off a main pipe is called?

Better luck next time!

#4. What are fixtures such as toilets, sinks, and faucets also known as?

Oh, so close. But, no. Try again!

#5. What types of pipes will you find soldered joints?

Keep on studying, you’ve got this!

#6. For the water supply within a commercial hot water heating system, what kind of back flow prevention system can NOT be used?

This was a hard one. You’ll get it right next time!

#7. Before you can solder a pipe, what substance must you use?

Nice try, but wrong answer!

#8. What is the term that describes the purging of air from supply pipes?

Not quite right. Feel free to try again!

#9. What is the diameter of the smallest pipe that an underground vent can have?

Not an easy question, was it?

#10. What should floor drains for commercial sinks NOT have?

Don’t forget to study! This is an important one to know!

#11. The plumbing installation prior to the completion of walls, ceilings, or floors is called?

Consider studying some more!

#12. What is the name of the vertical pipe connected to the drainage system and protrudes from a roof?

Better luck next time!

#13. What is the name of the fitting that fits inside the hub of another fitting in order to reduce the size or alter the interior?

Practice makes perfect. Keep trying!

#14. The name of the cut off valve found where the water pipe comes out of a wall is called what?

Brush up a bit more on your basic plumbing information.

#15. What valve would you use to tap into an existing pipe?

Don’t worry, you’ll get it next time.

#16. What device would you use to deter the water’s reverse flow (you usually need to use it with an exterior spigot head)?

That was a really tough one but you need to know it so open your books and study!


Basic plumbing practice test has questions and answers related to what you learn at plumbing trade school program, technical college and during apprenticeship. To work as a plumber, you’ll need to take a certification exam. Thinking about school? Find a trade school near you.

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This is a practice test and not official, it is for entertainment purposes only.