Design through physics and differential equations.

This paper is Ig® Nobel Physics Prize Winner 2026 https://improbable.com/ig/winners/

Worth noting that this study was partially funded by the university of Waterloo

TLDR: The "Cornucopia" has the least amount of splashback, however the "Nautilus" is the recommendation of choice, to accommodate ease of cleaning and variations in the height of the user.

https://academic.oup.com/pnasnexus/article/4/4/pgaf087/80987...

The secret to splash free male urination is..sitting down.

It’s not much help if the aim is off

Traditional urinals [1] are very effective. As are the steel variants [2]. The latter tend to become very grim over time.

[1]: https://www.hlwashrooms.co.uk/healey--lord-niagara-urinals--...

[2]: https://acornthorn.co.uk/urinals-wcs-cubicles/urinals/ur068-...

Somebody tell Larry David about this

I really like the inverted version, where it's almost guaranteed to splash yourself as a deterrent.

This reminded me of some scenes in the videogame Dispatch [1]

[1] : https://static.wikia.nocookie.net/dispatch/images/c/ca/Dispa...

> droplets which travel back onto the floor and user

I suppose this disproves Tufte's "There are only two industries that call their customers 'users': illegal drugs and software."

The recent introduction, in the UK at least, of splash-back reducing urinal … mats (?) has basically solved the problem in my opinion. They’re a disposable (but not single use…) plastic freshening insert with loads of short rubber strands, closely packed.

You can pee on one of these mats and the stream almost aerates itself on impact and you get basically no splashback, I guess with a similar mechanism to how an aerating tap produces a stream of water that doesn’t splash off whatever it hits.

Sustainability?

What resource will we run out of if we continue to piss in traditional urinals?

Has bullshit marketing terms invaded scientific papers now as well?

Direct link to the designs (c and d, with d being practical). Great paper honestly.

https://academic.oup.com/view-large/figure/512223725/pgaf087...

Global sustainability and accessibility seems a bit grandiose lol. It’s just a urinal after all. That being said, it’s been 4 years since Waterloo first determined this and it’s still unavailable to purchase. I’ve been patiently waiting for one to install in my shop but it seems like it’s not all that important for the globe if it’s still unavailable 4 years later.

The previous design was piss-poor

Sometimes i am using an urinal and i feel like no engineers were involved in the design. Glad to see someone is actually approaching this with proper science.

There is more to it than the splashback tho. Sometimes it seems that the surfaces that already have splashes on them are not angled properly to lead the water to the drain. This seems to create need to have sharp edge/lip rather than round one, which might be tricky to make resilient in porcelain. But the rounded lip certainly allows for droplet flow towards the user rather than the drain hole.