Urine doesn’t belong on the floor, and it definitely doesn’t belong on our clothes. An experimental new urinal design could help keep it from getting to those locations, by virtually eliminating the evils of “splashback.”
The modern urinal as we know it originated over a century ago, for use by industrial workers in Europe.
Its design has changed little since then, still incorporating an inner surface that sits at a 60- to 90-degree angle relative to the user’s urine stream. Because this angle is so sharp, much of the urine tends to splash off the surface upon impact, ending up on floors, shoes, and pants.
Although urine contains little in the way of bacteria, it still forms a smelly mess that needs to be cleaned up from public bathrooms. Doing so consumes water, requires the use of often eco-unfriendly cleansers, and adds an unpleasant task to janitors’ daily duties.
In an effort to address that problem, scientists from Canada’s University of Waterloo (appropriately enough) set about redesigning the humble urinal.
As part of their research, they set up a testing platform in which a urethra-shaped nozzle was used to deliver a controlled jet of dyed water from various heights, onto a glass plate that could be set to a variety of angles. It was ultimately found that angles of no more than 30 degrees worked best for reducing splashback.
The scientists proceeded to build a number of prototype urinals based on these findings, which also incorporated features such as a more closed design that better captured any urine that did splash. These models were then tested with the nozzle and dyed water, along with paper on the floor which highlighted any liquid that fell on it.
While a rather Cybertruck-looking design known as the Cornucopia proved to be ideal for users of a certain height, the Nautilus urinal performed best overall. Not only does it accommodate users of a wide variety of heights, it also has an easy-to-clean design plus it tolerates poor aim, potentially making it idea for use in aircraft, boats or trains.
And very importantly, splashback from the Nautilus was only 1.4% of that from traditional urinals, under certain circumstances. It is thus calculated that in the US alone, switching over to the Nautilus urinal could result in water savings of up to 10 million liters (2.6 million US gal) per day.
A paper on the research, which was led by Zhao Pan and Kaveeshan Thurairajah, was recently published in the journal PNAS Nexus.
Source: PNAS Nexus via EurekAlert