Splash-free urinals (2025)

(academic.oup.com)

101 points | by u1hcw9nx 1 hour ago

24 comments

  • danjc 1 hour ago
    Worth noting that this study was partially funded by the university of Waterloo
  • d-e-r-e-k 59 minutes 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 8 minutes ago
      Same attitude that prevents the urinal manufacturers from switching I reckon
  • u1hcw9nx 1 hour ago
    Design through physics and differential equations.

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

  • harvie 53 minutes 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.

  • danw1979 1 hour 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.

    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 1 hour 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.

  • enahs-sf 7 minutes ago
    They have had these in Japan for a while now it feels like.
  • geekamongus 20 minutes 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.
  • fedeb95 4 minutes ago
    it includes an anti-urination idea for outdoors, which may be worth noting.
  • walthamstow 36 minutes 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 25 minutes ago
      My stream doesn't have constant pressure throughout the process ;-)
  • freezystem 18 minutes 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.
  • ahoka 1 hour ago
    I really like the inverted version, where it's almost guaranteed to splash yourself as a deterrent.
  • plasma_beam 1 hour ago
    The secret to splash free male urination is..sitting down.
    • shermantanktop 8 minutes ago
      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.

    • bluebarbet 1 hour ago
      In a public toilet? Not happening. Back to square one.
      • Ylpertnodi 1 hour ago
        Always carry wipes?
      • quickthrowman 1 hour ago
        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?
        • footydude 16 minutes ago
          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 would be 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.

          • shermantanktop 5 minutes ago
            The gents loo at a non-posh UK pub is about the lowest you can go in the western hemisphere.
        • denkmoon 31 minutes ago
          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.
          • short_sells_poo 11 minutes ago
            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.

    • scythe 49 minutes ago
      Even women won't consistently sit down on public toilets
  • falcor84 1 hour 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."

  • masfuerte 1 hour 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-...

  • y-curious 1 hour 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...

  • nelox 1 hour ago
    It’s not much help if the aim is off
    • consp 1 hour ago
      Install the urin-no next to it to help "improve" the aim.
  • b3lvedere 1 hour ago
    This reminded me of some scenes in the videogame Dispatch [1]

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

  • vasco 3 minutes 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.

  • Razengan 14 minutes ago
    Just pee in the sink
  • shafyy 1 hour ago
    Somebody tell Larry David about this
    • trwhite 1 hour ago
      No defecation allowed
  • ButlerianJihad 52 minutes ago
  • fguerraz 55 minutes ago
    The previous design was piss-poor
  • asdfasvea 1 hour ago
    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?

    • vlyan 24 minutes ago
      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.
    • bobsmooth 1 hour ago
      Water and chemicals spent on cleaning. Less splash means less cleaning.
  • manarth 1 hour ago
    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...