A urinal designed to avoid urine splashback on the user and the floor will improve sanitation, bathroom cleanliness, and user experience.
Urinal designs have not materially changed in over a century. The style of urinal that was elevated to the status of artistic landmark by Marcel Duchamp in his 1917 dada art piece "La Fontaine" would not look out of place in today's public restrooms. Use of a typical public urinal often results in splatter of urine outside the confines of the device—onto the floor and, most unpleasantly, onto the user, a situation that creates costly messes to clean and risks transmitting disease. Zhao Pan, Kaveeshan Thurairajah, and colleagues calculated that when the flow of urine impinges on the surface of the fixture at 30◦ or less, splashback is greatly reduced. Experimental results confirmed this. The authors then designed urinals by solving differential equations, dubbed Cornucopia and Nautilus, which have impinging angles at or below 30◦ across their entire area. The Nautilus design has an additional advantage: it fits a range of urination heights, making it easier for children and people who use wheelchairs to use. According to the authors, if the 56 million urinals in public restrooms in the US were replaced with the Nautilus, it would prevent one million liters of urine from splashing onto the floor each day.
