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.
Splash-free urinals (2025) (academic.oup.com)
226 pointsby u1hcw9nx2 days ago131 comments
danw1979 2 days ago
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.
RattlesnakeJake 2 days ago
We've had those in the US for several years now, and they work really well.
I did encounter an upside-down one yesterday. That was... counterproductive.
jkubicek 2 days ago
I was on a work trip to Indianapolis last week and encountered two separate urinals with plastic screens branded by the same supplier. One screen was branded so that the plastic fingers point towards the user, one was branded so that the plastic fingers pointed towards the drain (i.e. the wrong way).
Makes me wonder why. Was that a misprint? Did someone get confused about the correct direction for the fingers?
RoadieRoller 2 days ago
My hunch.
The plastic fingers pointing up will reduce splash when our urine hits them first time, but if the bottom of the urinal is flat, the plastic will stick to it causing the urine flow to be slow, and due to capillary action, the urine rises above the fingers and causes splash again a few seconds into our urine passing.
If the fingers are pointed downward, the urine seeping through the downward fingers can flow freely to the outlet, and causes less splash with the urine rising through capillary action. The holes on the plastic layer will anyway avoid the urine splashing when we point our pipe against it.
Kerode0 2 days ago
An upside down urinal thing? I'd assume they're double sided..
xyzelement a day ago
Just flip it over.
Idealness9553 20 hours ago
The number of places I've encountered these upside-down is mind-boggling
ruszki 2 days ago
The worst urinal which I used was in Brussels about 15 years ago, and with that "splash-back reducing" mat. And it covered every part of the inner wall of the urinal. The mat caused the exact opposite of what it was supposed to do. It made it worse, and I had to wash my shorts, because it started to smell disgusting the next day.
SoftTalker 2 days ago
Yes this is the best solution I've seen. And every male pretty quickly figures out that the angle of the stream greatly affects splashback. Seems rather wasteful to spend money on this study for a solved/non-problem.
astrolx 2 days ago
And those, when they have a target on them (like football theme often seen in pubs in Europe) kinda combine the igNobel prize with the "Nobel" [0] prize on nudge !
[0] not a nobel prize but the prize of the swedish bank in memory of ...
Rendello 2 days ago
In my cleaning and maintenance work I'd replaced a lot of these. The orange ones I'm familiar with have a decently nice scent.
But last week I went to use my new shampoo and it had the same scent. On its own it would be nice enough but all I could smell was piss. Then I forgot and tried the same shampoo again a few days later to the same effect!
u1hcw9nx 2 days ago
Design through physics and differential equations.
This paper is Ig® Nobel Physics Prize Winner 2026 https://improbable.com/ig/winners/
d-e-r-e-k 2 days ago
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.
blurbleblurble 2 days ago
Same attitude that prevents the urinal manufacturers from switching I reckon
zdc1 2 days ago
I would love to see some Nautilus style urinals because--as a self-interested adult--splashback also hits me if the angle is bad enough. Sometimes I even use the stalls to avoid those porcelain tricksters entirely.
jonhohle 2 days ago
Things we take for granted, like washing hands, were pivotal in reducing illness in hospitals.
If 50% of the population walk out of a public bathroom without tracking urine on their feet or anything else that touched the floor and custodians have 99% less bodily fluids to deal with, that seems like positive progress. Maybe it will move the needle in ways that are unexpected.
hansvm 2 days ago
Yep. The next step is getting people to bother aiming for the urinal and hanging their member above it while shaking off any last drops. Till then, I don't think this design survives a collision with the real world.
sfink 2 days ago
There are a lot of reasons why something could get picked up, and sustainability is very low on the list. The manufacturers don't care; they get paid the same regardless of the amount of splashback. Most businesses won't care unless it significantly reduces maintenance overhead, and that's only going to happen if splashed urine is the determining factor in how frequently a bathroom gets cleaned. (As opposed to paper towels littering the floor, supplies running out, or the various disgusting things that happen in stalls.) Even if it were the determining factor, there would likely be pushback when people realize that better urinals lead to less frequent cleanings, and I wouldn't want to be the one having to justify the switch to people. And of course, if you already have a urinal, nobody's eager to buy a new one, and nobody's eager to discuss this particular topic.
The way I would see this happening is if users insist on it. And we likely won't until we experience one of these in real life, which makes it a chicken and egg problem.
There's also the argument that splash mats are a cheaper and even superior approach. That argument is unconvincing to me, because the ones I have experienced have been mostly ineffective, but it sounds like others' experience has been better. Maybe here in the US we just don't have very good ones? As a country, we've always been pretty bad at anything that seems gross. (Not that it's all that different in the rest of the West.) We have this naive faith in the ability of dry toilet paper to clean that which it can not, and disgust at alternative approaches that actually work. But that's a different topic. (Specifically, solids not liquids!)
legulere 2 days ago
> that's only going to happen if splashed urine is the determining factor in how frequently a bathroom gets cleaned
If you believe in the broken windows theory, there's not one determining factor: Splashes of urine make the bathroom look dirtier and lead to people not taking care of the bathroom properly.
sfink 18 hours ago
Huh. Having said that, I went to a movie theater over the weekend and they had a funky splash mat in their urinals. It was magical. I'd never seen one shaped like that before. (The usual ones I see have always seemed to make things worse.) Maybe I just don't get out enough.
brudgers 2 days ago
There are performant urinals in the market and have been for many years.
Talk to a local mechanical engineer who does plumbing design for recommendations that are available in your market and their probable cost.
If you are getting noticeable splashback, you have a very poorly designed urinal. The kind that gets architects angry calls from clients.
——
I used to work in architecture.
Rendello 2 days ago
I'm awaiting the Dyson splashless Suction Urinal.
shawn_w a day ago
As used by NASA and SpaceX.
Rendello 17 hours ago
That's right, I didn't even think of that. Now I'm reading this fascinating article:
xivzgrev 2 days ago
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
altmanaltman 2 days ago
I mean you're sad about a hypothetical. Why not consider the alternative where even your parents and teachers will probably not care because who wants to hear about a splash free uniral design from a kid in sixth grade. Like if some kid walked up to me with that, I would ignore them too sorry.
xivzgrev 2 days ago
Exactly. I wouldn't expect most teachers to take an interest. One it's outside of their area of knowledge and two it's beyond their job description.
But as I said, there are teachers who would. The right kind of teacher for this.
shevy-java 2 days ago
You would have been an excellent splash sputter scientist.
> I'm glad someone else has finally looked at this sticky situation
Wait ... your splash variants are sticky???
xivzgrev 2 days ago
Thanks!
Ha no, I'm just saying when pee dries. The article talked mostly about splash on the surrounding area vs self, though I was more concerned with the latter
dguest 2 days ago
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.
microtherion 2 days ago
I wonder whether a “Ig Nobel Price Winner” sticker would provide marketing benefits for an urinal.
gdisk1 2 days ago
Redirection of flow is greater than of more.
dang 2 days ago
Meet the Ig Nobel Prize Winners - https://news.ycombinator.com/item?id=49576611 - Sept 2026 (42 comments)
harvie 2 days ago
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.
abyssin 2 days ago
My pet peeve about urinals has to do with the way the separating walls are usually installed. It's systematically too low, as if their goal was to prevent splashing between each station instead of their role of visual privacy.
SoftTalker 2 days ago
Go visit an older stadium in the USA. Either no separating walls, or just a trough where you stand shoulder-to-shoulder with the people on your left and right. Eyes forward.
basisword 2 days ago
I very rarely see separating walls in the UK. Are they common in your country?
seszett 2 days ago
The US use separators between urinals but 5-cm gaps all around stall doors.
peddling-brink 2 days ago
> as if their goal was to prevent splashing between each station
Frankly, this is more important to me. I’m not looking around, and if someone else does, that’s their problem.
xyzelement a day ago
This is correct. We worry about getting someone's piss on us, not whether someone steals an admiring glance at our weiners.
cucumber3732842 2 days ago
Really old urinals don't splash back.
The engineers have spent the last 50yr trying to reduce water usage and material usage without making the product "noticeably" worse. Of course you add up 50yr of "it's 99% as good on our test, nobody will notice" and you get some degradation.
geekamongus 2 days ago
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.
wafflemaker 2 days ago
Solution to that problem would deserve a real Noble, not just an iG-one.
buck746 2 days ago
I stopped having that problem when I started taking a single square of toilet paper, folding it into a quarter square and using it to dab the tip a few times to get the last bit of liquid out. There's enough space to dab a few times with a different spot on the paper and folding it makes it thick enough to not have liquid go all the way thru. Since I started doing that I don't get the post restroom drip. Not really useful for a urinal, but it does work.
ahoka 2 days ago
I really like the inverted version, where it's almost guaranteed to splash yourself as a deterrent.
henryoz 2 days ago
There are historical examples of this in some alleys in central London (https://www.exploringgb.co.uk/blog/9th-century-urine-deflect...).
I remember being unpleasantly surprised by one after a particularly heavy New Year's as a student.
qingcharles 2 days ago
> The “urine-no,” a hostile antiurination surface
ravenstine 2 days ago
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!
gattr 2 days ago
A custom 3D-printed user-matched disposable nozzle, perhaps? One could carry a handful in his pocket and don before the act.
colinwilyb 2 days ago
I feel a laminar airflow which runs in parallel to the turbulent liquid flow to draw it into the receptacle would reduce waste.
What happens if you urinate through those bladeless Dyson fans?
Rendello 2 days ago
Laminar flow from the man?
I've seen youtubers achieve laminar flow by filling garden hoses with aligned drinking straws. Perhaps... there's an idea here...?
stevetron 2 days ago
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.
sph 2 days ago
I've seen plenty of stainless steel trough urinals in the pubs and clubs in the UK, and I'm now aware this sentence reads a bit funny.
falcor84 2 days ago
> 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."
drdeca 2 days ago
Most of the time someone uses a urinal, they didn’t purchase it. The customer is different from the user in this case.
xyzelement a day ago
That's often true in software as well. Perhaps it's actually the etymology of the term.
codethief 2 days ago
> 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!
Eridanus2 2 days ago
When ya hafta go.. Ya go.
readme 4 days ago
I'm honestly passionate about this topic. For a while, around the time that urinals started to appear without water, I dealt with some serious splashback issues. I forget when I started aiming for the back of the urinal. I'm assuming that's the deflection angle the paper discusses. At one point I realized, I was sometimes getting some pretty bad splashback. Perhaps because I stood close to the urinal. So I asked a colleague. He said he aims for the hole, and was confused why anyone would piss on the back of the urinal. I started doing that -- problem solved. I am for a direct hit, every time. The problem is that some urinals have a protector over the hole to prevent really smart people and children from putting paper towels in there. That thing is dome shaped, and multiplexes the stream like a lawn sprinker.
All of this, would not be necessary, if there were water at the bottom of the urinal.
Eridanus2 2 days ago
This assumes a fixed jet injection/intake vector... It's a floppy assumption at best, shaky at worst.
danjc 2 days ago
Worth noting that this study was partially funded by the university of Waterloo
pfdietz 2 days ago
Nominative determinism.
asdfasvea 2 days ago
Nice domain name too.
ahartmetz a day ago
I'm disappointed that it's not waterloo.wc or water-loo.wc
georgefrowny 2 days ago
And is on PNAS Nexus.
amelius 2 days ago
Now I have to go.
rigrassm 2 days ago
I come here for the stories and stay for comments like these.
tomaskafka 2 days ago
Sir, Reddit is that way
walthamstow 2 days ago
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!
aeyes 2 days ago
My stream doesn't have constant pressure throughout the process ;-)
masfuerte 2 days ago
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-...
dang 2 days ago
Related. Others?
New urinal designs - https://news.ycombinator.com/item?id=43668957 - April 2025 (126 comments)
Splash-free urinals: Design through physics and differential equations - https://news.ycombinator.com/item?id=43660617 - April 2025 (15 comments)
y-curious 2 days ago
Direct link to the designs (c and d, with d being practical). Great paper honestly.
https://academic.oup.com/view-large/figure/512223725/pgaf087...
mauvehaus 2 days ago
I love that La Fontaine is named in tribute to Marcel Duchamp[0], even if calling a splash-free urinal a fountain would seem a bit confusing on the surface.
y-curious 19 hours ago
Sorry, they use A and B as controls. They are not good at preventing splash
djmips 2 days ago
C looks challenging to clean
tshanmu 2 days ago
a surprising paragraph in the middle of the article "The “urine-no,” a hostile antiurination surface"
hbrav 2 days ago
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.
ttul 2 days ago
"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...
nelox 2 days ago
It’s not much help if the aim is off
consp 2 days ago
Install the urin-no next to it to help "improve" the aim.
freezystem 2 days ago
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.
enahs-sf 2 days ago
They have had these in Japan for a while now it feels like.