All About Urinals
Was having breakfast this morning with my friend Noah from GoMobo and we both commented on the fact that the urinal in the bathroom was filled with ice. Neither of us came up with a particularly good reason for it, so I decided to do some research when I got home. The best hypothesis I read is some combination of the ice acting as a “slow continuous flush” and help contains the smell (for those that have never seen it here’s some evidence).
While we’re on the topic of urinals (a strange one, I know), Noah and I also chatted briefly about fly decals in urinals (especially airports). He rightly pointed out that these help keep bathrooms cleaner by giving men a place to aim. As this site points out, “The interesting feature of these urinals is that they’re deliberately designed to take advantage of this inherent human male tendency.”
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First stop in conversations such as these must always be at The Straight Dope. Two long-ish quotes from a column called “Urinal 101: Aim for the back wall or the water?”
1) quote on shape:
The rear wall of the typical urinal is parabolic in cross section when viewed from above, and the porcelain finish is conducive to laminar flow. The principles of fluid dynamics tell us that a fluid striking a smooth surface at an oblique angle will tend to flow along that surface. Assuming the source of the fluid is near the focal point of the parabola–and modesty makes it unlikely he’ll stray too far–the fluid will run straight down the urinal wall with little or no splashing.
2) quote on flies and aiming:
When given a target, it seems, men instinctively aim at it. The fly was originally introduced at the Schiphol airport in Amsterdam, where it supposedly reduced spillage by 80 percent.