Science can help solve the  world’s most important problems, and what could be more important  than keeping pee off your shoes?

Yes, even the lowly urinal—and those who use it— can benefit from the  occasional peer-reviewed study. Keeping restrooms clean and  safe could all come down to the science of the shape  of the thing you pee in.

So let’s take a look at the science of urinals, and how folks are trying to make them better. [intro] Let’s establish a couple of facts. Fact number one: Urinals aren’t sterile. Surprise!

Urinals are like frat houses for bacteria. You probably don’t need a  scientist to tell you that, but in case you do… Research has confirmed what  we’ve always suspected, that the spaces under and between  urinals host a plethora of bacteria from a diverse range of species, from Corynebacteria to Rickettsiella  to good old Staphylococcus. Fact number two: Even the most practiced pee-er  can’t hit the bowl every time.

Anyone who has had the great pleasure  of relieving themselves near a urinal won’t need to refer to the scientific  data backing up this assessment, but in case you’re curious about volume,  someone did crunch those numbers. In the United States alone, the total amount of urine overflow  from our nation’s 56 million urinals is roughly 1 million liters. A day.

That’s a lot of wayward pee, and  a lot of habitat for bacteria. Gross, stinky urinals may seem like one of those immutable  fixtures of human civilization, but it is possible to build a better urinal. And people are trying.

Most efforts center around  a few important variables and how they can affect a urinal’s  splash and stink potential. First, the shape of the bowl. Second, fluid dynamics, or if you  like, the penis-to-urinal angle.

And finally, encouraging the  penis owner to actually care about whether the urine ends up in the urinal. Some urinal designers think adding a target will help with variable number three. Urinal designers in Japan did this  with cute, ladybug-shaped targets.

Why they picked ladybugs and  not bullseyes is anyone’s guess. In the Netherlands, a similar  design involves peeing on flies, which do seem somewhat more  deserving than ladybugs. This supposedly reduces spillage by 80%, but we couldn’t find a source for that number.

We can agree that it probably  does help, at least a little. Some urinals are outfitted  with a working soccer game. Just take aim and push the little ball  into the goal with your pee stream.

Some urinals even play music when you pee on them. Which is just kind of an odd  time to get Rick Rolled --. Still other entrepreneurial  designers have created urinals that play ads when you pee on them.

Because no corner of the world  should be free from advertising, even the one where you urinate. I’ll be honest, I would never  use that bathroom again. For those who have nothing  against flies or ladybugs, there are also bowls that look like mouths.

Ideally, mouths deemed worthy of being peed in, such as diabolical circus clowns  or your least-favorite politician. There are also flowers, religious figures, lips… it seems like urinal art is its  own bizarre little subculture. Most of these novel shapes aren’t  scientifically designed and tested, but there is some effort  within the scientific community to design better urinal shapes  based on fluid dynamics.

In other words, how does pee flow, and how can that knowledge be leveraged  to build a splash-free urinal? In a 2025 study, scientists compared urinal shapes to determine which ones  resulted in less splashback. Not with real pee, though.

Instead, they approximated the flow of human urine with a jet of dyed water from, and I quote, “an anatomically accurate nozzle.” So, basically a weewee-shaped squirt gun. They aimed their anatomically accurate nozzle at one of four different-shaped urinals. Then they soaked up the spilled  water with paper towels, and weighed the paper towels  to compare splash volume.

They found that splashback  is prevented when the stream hits a rigid surface at or  below an angle of 30 degrees. For standing users, the winning  design was named Cornucopia after its vague resemblance  to a Thanksgiving decoration I don’t see it, personally, but whatever Some scientists have proposed  more high-tech solutions for other urinal-related problems, like clogging and stink. In a 2019 study, researchers tested a system to help control the process of urea hydrolysis.

That’s the chemical reaction  that breaks down urea, the major waste product in urine,  into ammonia and carbon dioxide. And ammonia… is stinky. They were specifically interested in  urinals that don’t use water to flush, which have the potential to  improve wastewater quality.

The system they tested contains  pH and conductivity sensors that signal the release of acetic acid  when pH reaches a certain threshold. The acid inhibits urea hydrolysis, thus reducing the yuck and  stink levels in the urinal. Unfortunately, the biggest  variable in modern urinal design is the one nobody can really control.

A person has to actually care about whether or not their pee goes where it’s supposed to. Not everyone bothers to aim for the fly. Which means we’ve got to ask for  just a little bit more effort.

Oh, and while you’re at it… wash your hands! [ OUTRO MUSIC ]