alt Hacker NewsSplash-free urinals (2025)
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Ig nobel prizes were just a few days ago:
https://improbable.com/ig/winners/#ig2026
Edit: The splash free urinal was the winner for physics!
I once joked that these do more for science than Nobel prizes. Now I don't think it's a joke: "wacky but interesting" awards are more important for the advancement of science than "everyone agrees this these people should be even more famous" awards.
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.
I remember being annoyed by splash back in sixth grade. I mocked up an alternative design (essentially, a urinal that tilted away from you), and emailed some friends. They never responded, and I never followed up.
Looking back I feel sad - that's the kind of curiosity to nurture in a kid. But peers are rarely the best group, it would've been better to tell my parents or the right kind of teacher. My friends also could've said something: " I don't know what to do about this but you should tell ms blah blah blah", in a serious way not mocking way.
I'm glad someone else has finally looked at this sticky situation
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.
Design through physics and differential equations.
This paper is Ig® Nobel Physics Prize Winner 2026 https://improbable.com/ig/winners/
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.
No amount of engineering can solve the problem that no matter how much you jiggle, you shake, or you dance, the very last drop always falls in your pants.
I was in a Costco one, and the men's room urinal was a trough, a strainless steel trough! I thought it was 'cool'.
What they need to do with urinal design is to make one that can catch the wide-spray of someone who sports a PA.
I worked as a temp once in a stae government building. It didn't have enough bathrooms. The toilets were of the type that drained/fastened to the wall instead of the floor. One day, someone big sat down and broke it. There was an angry announcement on the rarely-used building-wide speaker. Nobody owned-up to it.
> The “urine-no,” a hostile antiurination surface:
> Instead of minimising splash, it can instead be maximized by setting […], see Fig. 7a. Although not suitable as a commonly practical urinal, it showcases the design philosophy. Such a surface could be installed outdoors to deter public urination as the offender would fall prey to enhanced splash-back. This hostile surface may be dubbed as “urine-no,” as shown in Fig. 7b.
Love it!
Even if a urinal doesn't splash, there's usually (always?) a decent amount of fine droplets that eject out from the stream since the flow is rather turbulent. On top of that, the fleshy opening is never completely stable.
What we really need is laminar flow!
The discussions section describes a solution to the opposite problem, where you optimise a surface for high splashback to deter people from peeing on it. Whether this makes the authors Lawful Evil or Chaotic Good is a matter of personal opinion, but they're definitely one or the other.
> 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."
I really like the inverted version, where it's almost guaranteed to splash yourself as a deterrent.
a surprising paragraph in the middle of the article "The “urine-no,” a hostile antiurination surface"
Just aim at the sweet spot where your stream smoothly swirls into the plughole. No spray, minimal sound. Most toilets and all urinals have this spot you can hit. In Amsterdam airport they even mark it for you with a crosshairs!
Direct link to the designs (c and d, with d being practical). Great paper honestly.
https://academic.oup.com/view-large/figure/512223725/pgaf087...
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-...
"Canadian who helped design splash-free urinal is proud of his weird science award"
https://www.cbc.ca/radio/asithappens/2026-ig-nobels-9.733140...
> High-speed images of splash events generated by flow from an anatomically accurate nozzle
They had some fun writing this.
European closets have the same issue. Indian closets does not. Actually Indian closets are superior in every way if you have good knees...
They have had these in Japan for a while now it feels like.
Nice, but does it takes into account that some droplets are directly issued from the hose itself ? Not to mention the double stream problem ^u^ Cool paper nonetheless.
The secret to splash free male urination is..sitting down.
This reminded me of some scenes in the videogame Dispatch [1]
[1] : https://static.wikia.nocookie.net/dispatch/images/c/ca/Dispa...
it includes an anti-urination idea for outdoors, which may be worth noting.
That takes all the fun out of using public toilets.
One of the more interesting scientific studies was the behavioural change of when you put down the image of a fly on an urinal. These flies are suddenly targeted by strong streams as if there is no tomorrow ...
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?
Just pee in the sink
Honestly not a bad idea
> At Amsterdam’s Schiphol airport, the use of fly stickers to change aiming behavior resulted in a reportedly 50–80% reduction (not elimination) in splashback observed and an 8% reduction in cleaning costs
It's surprising it's that high (8%). I would imagine it takes as long to mop a floor that has pee droplets or mop a floor that doesn’t. And someone still needs to mop the bathroom floor anyway and go into the bathroom anyway. Unless you pay the cleaners by hour instead of having them on payroll, monetarily I don't see the difference.
I expect cleaning costs to be dominated by the long tail, ie every bathroom cleanup job being the same except for the odd time when someone threw up on the floor or sprayed poop on the walls or what have you.
Still nice to not get pee on yourself though, that part is good.
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...
Worth noting that this study was partially funded by the university of Waterloo