6 ms·
Splash-free urinals (2025)
- readme 12d agoI'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.
- LorenPechtel 12d agoThe basic problem is that making the angle low makes the urinal take up more space. Businesses don't like that.
- u1hcw9nx 9d agoDesign through physics and differential equations. This paper is Ig® Nobel Physics Prize Winner 2026 https://improbable.com/ig/winners/ https://improbable.com/ig/winners/
- danjc 9d agoWorth noting that this study was partially funded by the university of Waterloo
- pfdietz 9d agoNominative determinism.
- asdfasvea 9d agoNice domain name too.
- deleted 9d ago[deleted]
- ahartmetz 9d agoI'm disappointed that it's not waterloo.wc or water-loo.wc
- georgefrowny 9d agoAnd is on PNAS Nexus.
- amelius 9d agoNow I have to go.
- rigrassm 9d agoI come here for the stories and stay for comments like these.
- tomaskafka 9d agoSir, Reddit is that way
- plasma_beam 9d agoThe secret to splash free male urination is..sitting down.
- bluebarbet 9d agoIn a public toilet? Not happening. Back to square one.
- quickthrowman 9d agoI fail to understand why anyone is scared to place their bare thighs on a public toilet seat. Do you have open wounds on your legs?
- denkmoon 9d agoI don’t care if my bare thighs were coated in the most potent prophylaxis known to man, I am not sitting on another man’s piss and or shit.
- short_sells_poo 9d agoYeah, 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. Shows also that money doesn't buy class.
- mschuster91 9d agoIn 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?
- 9d ago
- manarth 9d agoTLDR: 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/pgaf087/8098745#512223725 https://academic.oup.com/pnasnexus/article/4/4/pgaf087/80987...
- nelox 9d agoIt’s not much help if the aim is off
- consp 9d agoInstall the urin-no next to it to help "improve" the aim.
- masfuerte 9d agoTraditional 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---floor-standing-161-c.asp https://www.hlwashrooms.co.uk/healey--lord-niagara-urinals--... [2]: https://acornthorn.co.uk/urinals-wcs-cubicles/urinals/ur068-floor-standing-trough-urinal https://acornthorn.co.uk/urinals-wcs-cubicles/urinals/ur068-...
- shafyy 9d agoSomebody tell Larry David about this
- trwhite 9d agoNo defecation allowed
- ahoka 9d agoI really like the inverted version, where it's almost guaranteed to splash yourself as a deterrent.
- henryoz 9d agoThere are historical examples of this in some alleys in central London (https://www.exploringgb.co.uk/blog/9th-century-urine-deflectors-in-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 9d ago> The “urine-no,” a hostile antiurination surface
- b3lvedere 9d agoThis reminded me of some scenes in the videogame Dispatch [1] [1] : https://static.wikia.nocookie.net/dispatch/images/c/ca/Dispatch_capsuleArt.png https://static.wikia.nocookie.net/dispatch/images/c/ca/Dispa...
- falcor84 9d 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 9d agoMost of the time someone uses a urinal, they didn’t purchase it. The customer is different from the user in this case.
- xyzelement 9d agoThat's often true in software as well. Perhaps it's actually the etymology of the term.
- danw1979 9d agoThe 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.
- RattlesnakeJake 9d agoWe'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 9d agoI 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 9d agoMy 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 9d agoAn upside down urinal thing? I'd assume they're double sided..
- asdfasvea 9d agoSustainability? 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?
- bobsmooth 9d agoWater and chemicals spent on cleaning. Less splash means less cleaning.
- deleted 9d ago[deleted]
- vlyan 9d agonot 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.
- SoftTalker 9d agoThere 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.
- y-curious 9d agoDirect link to the designs (c and d, with d being practical). Great paper honestly. https://academic.oup.com/view-large/figure/512223725/pgaf087f4.jpg https://academic.oup.com/view-large/figure/512223725/pgaf087...
- mauvehaus 9d agoI 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. [0] https://en.wikipedia.org/wiki/Fountain_(Duchamp) https://en.wikipedia.org/wiki/Fountain_(Duchamp)
- y-curious 8d agoSorry, they use A and B as controls. They are not good at preventing splash
- djmips 9d agoC looks challenging to clean
- d-e-r-e-k 9d agoGlobal 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 9d agoSame attitude that prevents the urinal manufacturers from switching I reckon
- zdc1 9d agoI 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 9d agoThings 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 9d agoYep. 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 9d agoThere 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!)
- fguerraz 9d agoThe previous design was piss-poor
- treetalker 9d agoPiss-rich?
- harvie 9d agoSometimes 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 9d agoMy 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.
- peddling-brink 9d 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.
- SoftTalker 9d agoGo 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 9d agoI very rarely see separating walls in the UK. Are they common in your country?
- seszett 9d agoThe US use separators between urinals but 5-cm gaps all around stall doors.
- 9d ago
- ButlerianJihad 9d agohttps://en.wikipedia.org/wiki/Urinal_target https://en.wikipedia.org/wiki/Urinal_target
- walthamstow 9d agoJust 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 9d agoMy stream doesn't have constant pressure throughout the process ;-)
- geekamongus 9d agoNo 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 9d agoSolution to that problem would deserve a real Noble, not just an iG-one.
- deleted 9d ago[deleted]
- buck746 9d agoI 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.
- freezystem 9d agoNice, 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.
- Razengan 9d agoJust pee in the sink
- enahs-sf 9d agoThey have had these in Japan for a while now it feels like.
- fedeb95 9d agoit includes an anti-urination idea for outdoors, which may be worth noting.
- vasco 9d ago> 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.
- kadoban 9d ago> 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. You might have to mop more often from complaints or inspection, maybe?
- vasco 9d agoI don't think so, in every public place I've been they have a schedule and need to sign they did the cleaning at that time they had in the schedule.
- kadoban 7d agoWay back when I worked in a restaurant, there was that but then also if a customer complains they also go clean. They're never going to be like "Oh, someone shat on the floor? We'll deal with that at the next scheduled cleaning."
- xivzgrev 9d agoI 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 9d agoI 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 9d agoExactly. 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 9d agoYou 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 9d agoThanks! 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
- NotRedFox 9d agoHonestly not a bad idea
- ravenstine 9d agoEven 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 9d agoA custom 3D-printed user-matched disposable nozzle, perhaps? One could carry a handful in his pocket and don before the act.
- colinwilyb 9d agoI 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 9d agoLaminar 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...?
- qsera 9d agoEuropean closets have the same issue. Indian closets does not. Actually Indian closets are superior in every way if you have good knees...
- linkregister 9d agoIn 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.
- qsera 9d ago> a conscientious user can tidy their contact surfaces with toilet paper. I don't understand, because in a squat toilet, there is no contact surface!
- vintermann 9d ago> High-speed images of splash events generated by flow from an anatomically accurate nozzle They had some fun writing this.
- dguest 9d agoIg nobel prizes were just a few days ago: https://improbable.com/ig/winners/#ig2026 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 9d agoI wonder whether a “Ig Nobel Price Winner” sticker would provide marketing benefits for an urinal.
- gdisk1 9d agoRedirection of flow is greater than of more.
- dang 9d agoMeet the Ig Nobel Prize Winners - https://news.ycombinator.com/item?id=49576611 https://news.ycombinator.com/item?id=49576611 - Sept 2026 (42 comments)
- shevy-java 9d agoThat 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 ...
- codethief 9d agoMaybe an opportunity for a hydroelectric power source?
- stevetron 9d agoI 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 9d agoI'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.
- ttul 9d ago"Canadian who helped design splash-free urinal is proud of his weird science award" https://www.cbc.ca/radio/asithappens/2026-ig-nobels-9.7331408 https://www.cbc.ca/radio/asithappens/2026-ig-nobels-9.733140...
- tshanmu 9d agoa surprising paragraph in the middle of the article "The “urine-no,” a hostile antiurination surface"
- hbrav 9d agoThe 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.
- codethief 9d 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 9d agoWhen ya hafta go.. Ya go.
- meindnoch 9d agoI simply use a catheter and avoid such problems.
- quaverquaver 9d agoit is hilarious that they include Marcel Duchamp in this discussion! https://en.wikipedia.org/wiki/Fountain_(Duchamp) https://en.wikipedia.org/wiki/Fountain_(Duchamp)
- SH1-0151 9d ago[dead]
- alun 9d agoThe Cornucopia looks like the cybertruck of urinals.
- koenraad 9d agoAs 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.
- MD1032 8d agoAll Muslim men (and a lot of men from the middle east and south Asia + Japs I think) sit down to pee and WASH with water. People will say that's filthy, but don't you wash down there when you're showering? You clean your hands with soap anyway. No splashing on your clothes, loo or floor.
- joebig 9d ago'Cornucopia' looks hard to clean. Though with that name someone may be willing to dig through it.
- Eridanus2 9d agoThis assumes a fixed jet injection/intake vector... It's a floppy assumption at best, shaky at worst.
- khazhoux 9d agoI always use the kids urinal, the single urinal that is mounted low to the ground. Otherwise, the urinals are always so high, sometimes it feels like I'm about to rest my frank & beans on the urinal lip. No thanks!
- xyzelement 9d agoHow tall are you? For reference, my 6 year old is starting to use the regular size urinals without "resting his frank & beans" on it.
- nullorempty 9d agoYeah, rockets to Mars and splash-less urinals - the problems of one century
- dang 9d agoRelated. Others? New urinal designs - https://news.ycombinator.com/item?id=43668957 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 https://news.ycombinator.com/item?id=43660617 - April 2025 (15 comments)
- elzbardico 9d ago> 10E6 liters of splashback per day in the US alone. Yeah, kinda scary, but I wish they expressed this is freedom units instead of communist liters. How many 747 cargo holds or olympic pools are we talking about?