Do You Know These Things That Plumbers Should Know?


By: Torrance Grey

6 Min Quiz

Image: andresr/E+/Getty Images

About This Quiz

A bit of plumbing trivia: In 2008, a plumber named Joe Wurzelbacher became a household name after he spoke out against Barack Obama's tax plan at a town-hall meeting. Obama's opponent, Sen. John McCain, referred to "Joe the Plumber" in later speeches, making him an icon of working, middle-class America.

OK, we admit that plumbing is very rarely a route to 15 minutes of fame; Wurzelbacher was an exception. However, few jobs are as vital, and recession-proof, as plumbing. When economic times get tough, people might skip their vacations, cancel the cable and trim the grocery bills ... but if the toilet stops working, they're going to open up their checkbook! For this reason, although plumbing is considered a working-class job, it's also a very desirable one. A veteran plumber can make an excellent income. There are some drawbacks, of course, like the risk of scalding from hot water, exposure to liquid drain opener (Drano and Liquid Plumber, which homeowners sometimes use before calling in an expert, is a very caustic base), and infectious disease (plumbers work closely with toilets; enough said). Good training is essential to minimize these risks.

If you've been wondering how you might fare in this always-needed field, start by trying our quiz on the things that plumbers know -- about pipes and drains, fixtures and sub-systems, and more. No toolbox needed; just sharp wits!

A building's plumbing is divided into two sub-systems. What are they?

While "hot and cold" is a fair guess based on the labeling of household faucets, a building's two systems are the drainage and supply systems. One supplies clean water, and the other carries away used or dirty water.


Do the supply and drainage systems ever overlap?

The two sub-systems must be kept separate. Supply water might be used for drinking or cooking, so there can't be any wastewater in the supply system. It's a health issue.


If water is safe to drink, we call it ...

You might have known this one from the "Jeopardy" category "Potent Potables," which refers to alcoholic drinks, not water. For our purposes, though, it's important to know that the supply sub-system delivers potable water.


A part of the plumbing system that users interact with, where supply and drainage systems meet, is called what?

"Fixture" is a broad term that includes sink, showers, tubs, toilets and more. An appliance is different -- it's a household machine that uses electricity, and might or might not have a water supply and drainage system (e.g., a dishwasher).


Which of these forces is primarily responsible for carrying away drainage water?

Gravity is the reason dirty water disappears easily down the drain, and through the pipes beyond that (unless there's a clog). Since gravity is everywhere, and free, it's a nifty solution!


The sharply curved pipe under a sink is called what?

This pipe is named for its shape, as a simple glance will confirm. When taking it apart, be sure to have a catch bucket or pan underneath. There's always water in the U-bend. Which leads us to this ...


Why is there water in the U-bend?

The water in the U-bend is a physical barrier against sewer gases, which are lighter-than-air and would otherwise permeate the house, causing a really unpleasant smell. A secondary benefit of the U-bend is that it's where you'll find lost rings and other objects that weren't supposed to go down the drain.


Which of these is NOT a recommended way of clearing a clog?

The other three are safe manual ways to clear a clog, though a drain stick (it looks kind of like a flat plastic twig with thorns on the sides) won't reach down very far. Liquid drain opener is not recommended because it can damage the pipes, and because if the clog doesn't clear, you don't want to accidentally get the standing water, with drain opener in it, on your skin.


Which of these is a nickname for a drain auger?

It doesn't take much imagination to realize that this device was nicknamed for its ability to wend its way through tight spaces and curves. This is how a drain "snake" finds a clog, which it then hooks into and pulls up up to the surface.


What role do vents play in a plumbing system?

In the drainage system, the solid and liquid waste goes to the sewer or septic tank. But gases have to be released at the highest possible point in a building, in order not to create noxious air near ground level. Vent pipes make this possible. They also provide oxygen to aid in aerobic breakdown of waste.


What is another name for the curve of the U-bend, where water pools and jewelry gets caught?

We refer to this part casually as "the trap." Most plumbers have experience of taking apart a trap in order to retrieve something valuable caught there, like an engagement ring.


Why is having two traps in one line frowned on?

Traps are an essential part of the drainage sub-system, as we learned in another question. However, they are also a risk for clogs. Two traps are unnecessary, and so plumbers avoid the extra risk by only using one per line.


The best way to prevent drain clogs is ...

Hair is the biggest culprit in drain clogs. Gradually, it gets covered in that smelly black scum that lives in drain pipes, and becomes nearly solid. At that point, either the homeowner or a plumber has to take action.


Which kind of tape do plumbers often use?

Teflon tape has the valuable quality of adhering so closely to the threads at the ends of pipes that they still operate as threads. That is, they allow the pipes to be screwed together. This makes Teflon tape very useful in plumbing.


Do plumbers ever work on water heaters?

Water heaters are more "plumbing-adjacent" than an intrinsic part of the plumbing system. Some plumbers might feel comfortable working on them, but others might want to call in a repair person with expertise in that area.


About how hot should a household's heated water be?

80 degrees is a good temperature for a swimming pool, but that's still cool to the touch. However, 210 is two degrees shy of boiling -- much too hot. 120 degrees is about as high as you'd want tap water to go.


If water is seeping from a toilet tank into the bowl and wasting water, which of these is likely to blame?

The flapper is the movable cap over the flush valve, which releases water from the tank into the bowl during a flush. It's an easy fix, and frankly most homeowners could do it for themselves rather than call in a plumber.


In which of these would you likely find an "aerator"?

Aeration means that air is introduced into the water supply, so that less water is used but the person showering doesn't feel a lack of water pressure. However, if overdone, aeration can make you feel like you're being "sandblasted" by your shower ... so find a happy medium.


What is "graywater"?

"Graywater" is a term that's popular with environmentalists. For example, an eco-minded person might keep a bucket in the shower to catch some water, then use that to water plants. It's a consumer's way to get around the strict separation of the supply and wastewater systems.


Which of these human body parts gives its name to a plumbing part?

An "elbow" is a small connecting piece, usually bent at a 45-degree angle. It bridges the gap between two longer pieces pf pipe and allows for a change of direction.


Which of these is NOT a term used in plumbing?

"Waterspout" is a term from meteorology. It refers a tornado that forms over a body of water instead of land. Don't confuse it with "downspout," which is a pipe that carries water down from a roof (and also isn't part of a plumbing system, but rather of a rain-gutter system).


What is a braided hose designed to do?

Braided hoses are designed to be flexible. You'll see them in tight spots, like under the sink. Similarly, a drain auger has many small plates that bend as it goes through pipes looking for a clog.


Which of these items is a risk to clog toilets?

It's true that you might get away with throwing these things down the john, but it's really not the best idea. One of them not making it through to the main can lead to another getting caught against it, and then another ... you see where this is going.


Which of these fixtures is exempt from needing a drainage pipe?

In your garden or yard, you probably have a faucet that lets water splash directly onto the ground. The soil itself is the drainage system; no pipe is needed. Everywhere else in the home, there has to be a way for water to get into the drainage subsystem.


In which of these fixtures would you find a "basket strainer"?

All sink drains have built-in strainers, out of sight. But a simple strainer that fits into the drain opening, and can be removed by hand and emptied, is known as a basket strainer.


What does a "fitting" do?

Faucet knobs and showerheads are examples of fittings. They are part of fixtures, but not the same thing. They should not be used interchangeably.


Under U.S. regulations, what is the maximum amount of water that one flush can use?

In the early to mid-20th century, this amount was higher, closer to three gallons. Makers of plumbing fixtures have become increasingly concerned about water conservation as environmentalism has moved into the mainstream.


Which of these metals is a popular choice for pipes carrying tap water?

Lead was the popular choice in Roman times, so much so that the word "plumbum," meaning lead, gave us our modern-day terms. However, as the health risks became known, copper became the go-to metal.


The breakdown of metal into sulfide or oxide form, such as rusting, is called what?

Rust is the most common, well-known form of corrosion. Plumbers will see a lot of this in their day-to-day work. Some metals are more corrosion-resistant that others, though.


Other than lead, which of these did the ancients use for pipes?

Mud would dissolve when exposed to water; the pipes would have no integrity. However, humans used all the other materials listed above, showing surprisingly ingenuity in their engineering.


Backflow prevention devices keep what from happening?

As pointed out earlier, the supply (potable water) sub-system and the drainage (wastewater) sub-systems are separate. But emergencies, like a water main break, can cause water pressure in the supply system to drop markedly and allow unclean water from elsewhere into the pipes. It's this situation that a backflow device is designed to prevent.


Do plumbers empty septic tanks?

This is a specialized (and dirty) job. A company that empties septic tanks has already arranged for a place to take the waste that is approved by state and local regulations, which is a key part of the job. This falls outside a plumber's domain.


A customer wants a plumber to install an ADA toilet. How is it likely to be different from her old toilet?

"ADA" stands for the American with Disabilities (Act), and doorways, stairways, furniture and fixtures that are ADA-compliant are ones built to be more easily used by people with disabilities. Such a toilet is always taller than a standard one, to allow for easy transfers from a wheelchair, or ease of sitting down for users of walkers and crutches.


Consumers buy dual-flush toilets because they are ...

A dual-flush toilet allows the user to flush with the maximum amount of water (usually for solid waste) or a reduced amount (for just liquid). They have become popular since the environmental boom of the early 1990s.


Which of these is an essential rule of plumbing work you won't find in any textbook?

OK, this one is just for fun -- but true nonetheless! Plumbers work on toilets a lot, and the job involves a lot of other dirty work -- obviously, gloves or frequent handwashing are useful.


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