Splash-free urinals (2025) | Hacker News Reader

Splash-free urinals (2025)

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229 pointsu1hcw9nx132 comments

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.

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.

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.

An upside down urinal thing? I'd assume they're double sided..

Just flip it over.

The number of places I've encountered these upside-down is mind-boggling

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.

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.

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 ...

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!

Design through physics and differential equations.

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

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.

Same attitude that prevents the urinal manufacturers from switching I reckon

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.

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.

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!)

> 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.

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.

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.

I'm awaiting the Dyson splashless Suction Urinal.

As used by NASA and SpaceX.

That's right, I didn't even think of that. Now I'm reading this fascinating article:

https://en.wikipedia.org/wiki/Space_toilet

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

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.

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.

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???

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

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.

I very rarely see separating walls in the UK. Are they common in your country?

The US use separators between urinals but 5-cm gaps all around stall doors.

> 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.

This is correct. We worry about getting someone's piss on us, not whether someone steals an admiring glance at our weiners.

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.

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.

I wonder whether a “Ig Nobel Price Winner” sticker would provide marketing benefits for an urinal.

Redirection of flow is greater than of more.

Meet the Ig Nobel Prize Winners - https://news.ycombinator.com/item?id=49576611 - Sept 2026 (42 comments)

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.

Solution to that problem would deserve a real Noble, not just an iG-one.

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.

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

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.

> The “urine-no,” a hostile antiurination surface

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!

A custom 3D-printed user-matched disposable nozzle, perhaps? One could carry a handful in his pocket and don before the act.

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?

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...?

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.

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.

> 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."

Most of the time someone uses a urinal, they didn’t purchase it. The customer is different from the user in this case.

That's often true in software as well. Perhaps it's actually the etymology of the term.

> 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!

When ya hafta go.. Ya go.

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.

This assumes a fixed jet injection/intake vector... It's a floppy assumption at best, shaky at worst.

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

Nominative determinism.

Nice domain name too.

I'm disappointed that it's not waterloo.wc or water-loo.wc

And is on PNAS Nexus.

Now I have to go.

I come here for the stories and stay for comments like these.

Sir, Reddit is that way

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!

My stream doesn't have constant pressure throughout the process ;-)

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-...

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

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

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.

[0] https://en.wikipedia.org/wiki/Fountain_(Duchamp)

Sorry, they use A and B as controls. They are not good at preventing splash

C looks challenging to clean

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)

a surprising paragraph in the middle of the article "The “urine-no,” a hostile antiurination surface"

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.

"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...

It’s not much help if the aim is off

Install the urin-no next to it to help "improve" the aim.

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 ...

Maybe an opportunity for a hydroelectric power source?

I 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!

How tall are you? For reference, my 6 year old is starting to use the regular size urinals without "resting his frank & beans" on it.

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.

They have had these in Japan for a while now it feels like.

https://en.wikipedia.org/wiki/Urinal_target

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

In a public toilet? Not happening. Back to square one.

I 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?

I 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.

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.

Shows also that money doesn't buy class.

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?

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.

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.

The gents loo at a non-posh UK pub is about the lowest you can go in the western hemisphere.

a) sitting on piss

b) sitting on a seat you just wiped piss off

c) piss on the floor which will get on your trousers if you sit

Always carry wipes?

In my man-purse? Not enough space, what with the Swiss Army knife and travel can of WD-40 I'm already carrying.

Even women won't consistently sit down on public toilets

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.

European closets have the same issue. Indian closets does not. Actually Indian closets are superior in every way if you have good knees...

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.

> 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!

The basic problem is that making the angle low makes the urinal take up more space. Businesses don't like that.

'Cornucopia' looks hard to clean. Though with that name someone may be willing to dig through it.

> High-speed images of splash events generated by flow from an anatomically accurate nozzle

They had some fun writing this.

Somebody tell Larry David about this

No defecation allowed

it is hilarious that they include Marcel Duchamp in this discussion! https://en.wikipedia.org/wiki/Fountain_(Duchamp)

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

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

Yeah, rockets to Mars and splash-less urinals - the problems of one century

The Cornucopia looks like the cybertruck of urinals.

I simply use a catheter and avoid such problems.

> 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.

> 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?

I 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.

Way 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."

it includes an anti-urination idea for outdoors, which may be worth noting.

Just pee in the sink

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.

All 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.

> 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?

The previous design was piss-poor

Piss-rich?

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?

Water and chemicals spent on cleaning. Less splash means less cleaning.

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.

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.

Honestly not a bad idea

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...

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