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 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?
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.
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 ...
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.
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.
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
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
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.
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.
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.
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.
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.
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!)
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.
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.
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.
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.
> 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.
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.
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.
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.
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!
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.
As men, can we just sit down? For the last 10 years or so I have been doing exactly that and it’s been wonderful. Cleaner toilets, cleaner hands, cleaner clothing and no more annoying drips of pee in the boxers after the act because it relaxes the muscles more.
In practice a user will find the squat toilet to be superior until the user count increases above a dozen per hour. Then a single user will carelessly engage the spray hose and saturate the entire area. The area around the pit will be inundated with muddy water. Remediation requires a mop and bucket, which is likely only performed once daily.
An anatomically inferior sitting toilet in similar settings will often be soiled by careless users. However, a conscientious user can tidy their contact surfaces with toilet paper.
This has been my observation from my travels in the three continents I have been able to observe squat toilets in use.
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.
Can't speak for everyone but in my experience using public toilets (predominantly UK, pubs and train stations):
* there's not always a properly functioning seat / seat at all
* the seat is not always dry
* the cubicles do not always have a functioning lock
* the bowl is not always 'clear'...for reasons probably best left unexplored, people seem to choose public toilets as a place to carry out the most incomprehensible and unimaginable of all bowel movements. I've been greeted with bowls that let's just say would be benefit being assessed by a trained professional
Public toilets are also often pretty grim places in general due to the smells, sounds and general lack of hygiene/cleanliness.
All that said...IF the toilets look in decent repair I personally will use the cubicle and sit down, but it's probably less than 30% of toilets that feel like that's an option.
Also just to say I am someone who always sits to pee whenever at home/in a person's home and i'm not someone who anyone would ever call a germaphobe, so I do generally choose to sit rather than stand.
Yeah, the issue is that it takes one disgusting degenerate who doesn't know how to use a toilet and pisses all over the seat or worse.
I'm purposefully not calling these people uneducated, because I routinely encounter it in an environment full of highly paid and educated people with Stanford, Harvard, Princeton, etc... kind of education. These people come from money, earn money and are supposedly educated. And yet, they will happily piss all over the toilet seat and not even bother to clean it.
Agreed it's 100% not an education/money/class thing. I moved into a larger office, high tech company, and the number of times people need to be told not to leave the toilet in a state or to take their rubbish out of meeting rooms when they leave is eye opening. A large number of people from all backgrounds are just animals.
In the line of thinking of educated toilet shitters - why clean up after oneself when there is, from childhood, always some underpaid person of color that does the cleanup for you?
At home? 100%. Out in the world? Very much depends.
I was just in a stall where the inside of door had a pictogram forbidding users from standing on the edge of the bowl and squatting. I assume this might be for visitors from countries where squatting is common.
Point being, you just never know what random members of the public will do with a door to hide behind.
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 ...
There was a trend for a while for waterless/flushless urinals to save water. Though I would guess those have higher cleaning costs so not sure how that worked out in the end.
not so long ago it was very fashionable to include DEI/ESG/etc lip service in those things, regardless of whether it made sense. for example, I've read a study comparing leather tanning compounds and it had a completely out of place paragraph babbling about climate change. the author wasn't even American, it's a global cargo cult.
> 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://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.
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 did encounter an upside-down one yesterday. That was... counterproductive.
Makes me wonder why. Was that a misprint? Did someone get confused about the correct direction for the fingers?
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.
[0] not a nobel prize but the prize of the swedish bank in memory of ...
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
> I'm glad someone else has finally looked at this sticky situation
Wait ... your splash variants are sticky???
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
But as I said, there are teachers who would. The right kind of teacher for this.
This paper is Ig® Nobel Physics Prize Winner 2026 https://improbable.com/ig/winners/
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.
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.
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!)
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.
Frankly, this is more important to me. I’m not looking around, and if someone else does, that’s their problem.
> 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!
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.
What we really need is laminar flow!
What happens if you urinate through those bladeless Dyson fans?
I remember being unpleasantly surprised by one after a particularly heavy New Year's as a student.
I suppose this disproves Tufte's "There are only two industries that call their customers 'users': illegal drugs and software."
https://www.cbc.ca/radio/asithappens/2026-ig-nobels-9.733140...
[1]: https://www.hlwashrooms.co.uk/healey--lord-niagara-urinals--...
[2]: https://acornthorn.co.uk/urinals-wcs-cubicles/urinals/ur068-...
https://academic.oup.com/view-large/figure/512223725/pgaf087...
[0] https://en.wikipedia.org/wiki/Fountain_(Duchamp)
An anatomically inferior sitting toilet in similar settings will often be soiled by careless users. However, a conscientious user can tidy their contact surfaces with toilet paper.
This has been my observation from my travels in the three continents I have been able to observe squat toilets in use.
I don't understand, because in a squat toilet, there is no contact surface!
They had some fun writing this.
* there's not always a properly functioning seat / seat at all
* the seat is not always dry
* the cubicles do not always have a functioning lock
* the bowl is not always 'clear'...for reasons probably best left unexplored, people seem to choose public toilets as a place to carry out the most incomprehensible and unimaginable of all bowel movements. I've been greeted with bowls that let's just say would be benefit being assessed by a trained professional
Public toilets are also often pretty grim places in general due to the smells, sounds and general lack of hygiene/cleanliness.
All that said...IF the toilets look in decent repair I personally will use the cubicle and sit down, but it's probably less than 30% of toilets that feel like that's an option.
Also just to say I am someone who always sits to pee whenever at home/in a person's home and i'm not someone who anyone would ever call a germaphobe, so I do generally choose to sit rather than stand.
I'm purposefully not calling these people uneducated, because I routinely encounter it in an environment full of highly paid and educated people with Stanford, Harvard, Princeton, etc... kind of education. These people come from money, earn money and are supposedly educated. And yet, they will happily piss all over the toilet seat and not even bother to clean it.
Shows also that money doesn't buy class.
b) sitting on a seat you just wiped piss off
c) piss on the floor which will get on your trousers if you sit
I was just in a stall where the inside of door had a pictogram forbidding users from standing on the edge of the bowl and squatting. I assume this might be for visitors from countries where squatting is common.
Point being, you just never know what random members of the public will do with a door to hide behind.
[1] : https://static.wikia.nocookie.net/dispatch/images/c/ca/Dispa...
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 ...
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?
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.
You might have to mop more often from complaints or inspection, maybe?
https://academic.oup.com/pnasnexus/article/4/4/pgaf087/80987...