Can You Pass a Plumbing Certification Exam?



By: Zoe Samuel

6 Min Quiz

Image: shutterstock

About This Quiz

Plumbing has been with us since the earliest days of the Roman empire. It is the mark of civilization. The Romans were powerful in part because of their aqueducts, massive sewers, and the lead pipes from which plumbing draws its name (lead in Latin is "plumbum"). 

When a civilization grows, the growth of its water infrastructure has to come along with it or else it all falls apart. Joseph Bazalgette built the sewers of London, diverting rivers into pipes that took the water to the mouth of the Thames and out to sea, a huge improvement over the old paradigm of people using chamber pots and dumping them into the streets. With plumbing comes the health of a society, jobs, and engineering feats at which we still marvel.

Today, plumbing is much more than just installing toilets or water mains. Plumbing also covers gas pipes, which means that plumbing emergencies can be messy, or dangerous, or both. Plumbers aren't regular workmen. Their job is as technical as an electrician's and as crucial to the survival of a building as the work of a bricklayer. Plumbers have to be good with their hands, but they also need to be intelligent and detail oriented, or things can go badly very fast. Could you pass one of their certification exams?  Take the quiz and let's find out!

What do you call a device that discharges a predetermined quantity of water to fixtures for flushing purposes, but then is closed by water pressure?

The flushometer valve is the device that controls how much water goes into a receptacle, like your toilet. It is set to allow a specific amount, and no more.


What do you call a tank designed to receive raw sewage?

When you aren't connected to a municipal sewer, you have to have someplace to temporarily house your sewage. A septic tank is that device.


What do you call the thing that collects water from a building's roof?

Some plumbing vernacular is simple and straightforward, like this. It's a drain on the roof. Roof drain.


What do you call an exterior drainage pipe for storm water conveyance?

Outside pipes, such as those conveying water from the roof drain, are called leaders.


In plumbing terms, what is AGA?

While there is a range called an Aga, AGA refers to a trade organization in plumbing.


What do you call the single pipe that rises up a building like a hidden tree trunk, with pipes branching out to collect waste water?

When you hear that there is a problem with your home's stack, be afraid. Be very afraid. The drain stack is the backbone of your home's internal sewage system, moving water away from the bathrooms and kitchen. If it breaks down, you had better have a membership at a gym with a good bathroom, because you won't be using the one in your home.


What is water hammer?

Have you ever heard a mysterious noise coming from your building's pipes? That sound is not called "knocking" but rather "water hammer." In the case of pipes that go to faucets, it's probably just someone turning off the faucet upstairs, but from heating pipes, it could just be the boiler turning off.


What device should you use to reduce water hammer?

Air chambers absorb pressure, eliminating water hammer. To be correctly installed, they should be as close as possible to the valves or faucet and at the end of long runs of pipe.


What would you install to separate especially dangerous waste from regular waste water?

An interceptor is a device that separates hazardous substances from regular waste water, allowing the regular waste to be taken away by gravity.


What is a curb stop?

Getting to the water main is a pain, so often a curb stop is added, allowing the utility to turn off the water when you're having work done on a property, or if the bills haven't been paid.


What is a yoke vent?

You don't want a pressure problem, especially in your waste pipes. A yoke vent connects upward from a soil or waste stack to a vent stack, preventing pressure changes in the stacks.


What is a water closet?

"Water closet" usually refers to the entire bathroom, but in plumbing, it refers to the actual tank attached to a plumbing fixture, like a toilet.


What causes back siphonage?

Back siphonage is when water flows the wrong way in waste drainage pipes, upward. It's gross, and awful, and results from negative pressure in the pipe.


How many types of "air gaps" are there?

The two types of air gaps are the kind in the drainage system and the kind in the distribution system. All air gaps are defined by one specific detail -- unobstructed vertical distance through which free atmosphere exists and travels.


What is an air lock?

Simply put, an air lock is a bubble of air that restricts the flow of water in a pipe. This can be achieved a number of different ways.


From what doesn't a wet vent receive water?

Wet vents do not accept waste water from water closets, but do accept it from everything else.


What is a soil pipe?

The "soil" in soil pipe refers to the nature of the water within it. Soiled water (from bathrooms, etc.) is discharged through the soil pipe into the municipal sewer.


What is a STUDOR vent?

A STUDOR vent is a kind of air admittance valve. This type of valve is designed to regulate has pressure in sewage pipes without letting the smell come upward into a dwelling.


What is a P&T relief valve?

A "Pressure and Temperature Relief Valve," or "P&T relief valve" for short, is a valve used to regulate the safety of the hot water in a system, keeping the pressure and temperature from breaking the system.


What would you call a trap with a vertical inlet and a horizontal outlet?

A P trap is a piece of plumbing you come in contact with all the time. It's the bent pipe under your sink that allows some detritus to fall to the bottom of the trap, which can be opened to release it, rather than let it clog up some other part of the pipe.


What would you use to hang pipe on the underside of a ceiling, during construction?

All thread rod is something used by many types of builders, but in plumbing it is usually used to suspend piping under a ceiling during construction, later hiding the pipes within the structure.


What would you call a device designed to elevate water or liquid waste to a point of discharge where it can be drained away by gravity into a sewer?

Ejector pumps come in different sizes. Some are meant for use in homes, but there are some huge ejector pumps, like those used to pump sewage for municipal sewers.


What soil pipe isn't seen too much anymore?

Extra heavy soil pipes were commonly used to convey waste water to the sewer, but only when a large amount needed to be transported. Nowadays they are pretty rare, but sometimes still in use.


What is a sanitary sewer?

Some dwellings were built with two sewers, one for storm water and another for soiled water. Even stranger, these sewers nearly always combine in the municipal sewer that combines them.


What do you call a pipe that receives waste water from sources other than water closets?

"Wet vent" is the term for the pipe that receives waste water from sources other than the water closet.


What is a thermostatic mixing valve?

"Thermostatic Mixing Valve" is a fancy term for the faucet on your sink that has two knobs, one for cold and the other for hot, but only one spigot, so the temperature of the water can be controlled. This isn't just convenient, it prevents scalding.


What's another name for a float valve?

A floating valve or "ballcock" is so named because of a floating ball that, as the water around the valve rises, floats with it, closing the valve. You have one of these on the back of your toilet.


When sizing a piping system, what is the minimum flow rate for a shower, in gpm?

When setting up a shower, the ability of the shower to intake and expel water is of primary importance.


If you have a 75-foot long pipe to a sump vent, and not much information about the friction in it from fittings, etc. what is the assumed length of the pipe, in feet?

Like with voltage drop from putting electricity through a long cable, putting anything through a pipe doesn't mean you'll get out what you put in. By having bends or fittings attached to a pipe, it changes the way things flow through it, and thus the effective length of the pipe.


You're picking a sleeve for a 2-inch pipe that is going through a foundation wall. How big should the sleeve be, in inches?

A sleeve for a pipe needs some room for "play," meaning when the pipe expands or contracts, but it doesn't need to be huge.


What do you call a drainage branch pipe extending laterally from a soil or wastewater stack that receives discharge from two or more fixture drains?

It is important that every piece of plumbing kit has its own name and terminology so any plumber can stride into any situation and get things working.


In a building that requires five drinking fountains, how many fountains may be substituted with vending machines that sell bottled water?

Certain regulations allow plumbing needs to be circumvented through other technology. If the water main, budget, or building construction do not allow for the installation of pipes, then this can be gotten around through things like water vending machines.


In a bathroom that requires five water closets, how water closets in the men's bathrooms may be substituted with urinals?

Some rules around plumbing exist to give leeway to developers, while others exist to allow for things like a men's bathroom and a women's bathroom. This is one such case.


How thick, in inches, should the metal sleeve be around a pipe going through a concrete wall?

Not all walls require the same amount of protection for pipes, so most of the time, a pipe's sleeve need not be too thick.


How big must a shower waste strainer be, in inches?

To allow waste water to leave a fitting, like a shower, pipes need to be at least a certain size, and the strainer to keep waste from clogging up those pipes must be at least a certain size.


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