The best way to pee into a urinal, according to science

A team of physicists are on a crusade to make men's restrooms less disgusting

Man at urinal
(Image credit: (Thinkstock))

Now that we know the best way to get a bartender's attention, let's turn our attention toward the inevitable restroom break that will soon follow.

The sad truth is that men's restrooms aren't the most sanitary places, largely because adult human males are not very good at urinating, as if the male brain briefly shuts down whenever hands and penises join together.

But fear not! There is hope. Tackling the dire problem of urinal splash-back, a team of fluid dynamics researchers from Brigham Young University — who call themselves the "whizz-kids" — set out to discover the absolute best spot for dudes to aim at when they're relieving themselves.

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Now, perhaps you're the kind of guy who aims for the blue urinal cake at the bottom as if it were a Space Invader. Or maybe you take a step or two back to test your flow's strength. If you do either of these, I must kindly ask that you stop immediately. You're making a mess.

Both methods are prone to creating splash-back, which gets urine all over your shoes, and more embarrassingly, the front of your pants. Peepee pants are not a good look. Plus, you're leaving rude little puddles for the rest of us to awkwardly plant our feet around, depriving us of the basic dignity of a sturdy base. "We've all been in disgusting toilets with puddles on the floor," researcher Tadd Truscott told BBC News, "these places are a breeding ground for bacteria."

That splash is due to a fluid dynamics term called the Rayleigh Instability. Basically your stream loses power about 6 inches from the urethra, scattering your spray into messy droplets.

With a little effort, you can change. The physicists — using a nozzle and thankfully not the real thing to simulate how liquid flows from the male member — tested all sorts of peeing angles to figure out the safest way to urinate, and recorded the results on high-speed cameras. This, according to the study, is the optimal way to pee:

…men should stand as close to the urinal as possible they advise. Also helpful is directing the stream to hit the back of the urinal at a downward angle. That creates less splash-back and the drops that do bounce, head downwards into the urinal drain. Conversely, to prevent messing one's trousers (or angering neighbors) they suggest men not spray directly into the urinal or into the pool that forms at the bottom of the urinal, both cause a lot of splash-back. [PhysOrg]

Here is a helpful video demonstration, too:

So. Stand real close, aim for the back at a slightly downward angle, and let things flow naturally down the porcelain like a Zen waterfall. The guy next in line will thank you.

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