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Most of us have probably noticed the subtle difference between a toilet in a public bathroom and the toilets we have in our homes. It’s not overtly obvious, just a minor U shape rather than a full circle. But while we can recognize the differences, there is a reason for it.

For a start, the open-ended toilet seat is a result of the American Standard National Plumbing Code, meaning it is the standard for most public restroom setups.

Photo: Wikimedia Commons

This particular code was made back in 1955, but it wasn’t until 1973 when it was further solidified as the Uniform Plumbing Code by the International Association of Plumbing and Mechanical Officials, or IAPMO.

The IAPMO’s code reads, “Water closets shall be equipped with seats of smooth non-absorbent material. All seats of water closets provided for public use shall be of the open-front type.”

Photo: flickr/Lyn Lomasi

The idea for these rules all boils down to the concept of hygiene. The open front part of the toilet means that there is less surface area to come in contact with – at least that’s the idea. Same with the disposable toilet seat covers that have been created, although those aren’t as effective against germs as people might think.

According to Lynne Simick, the senior director of code development at IAPMO, both the toilet seat covers and the toilet seats themselves were designed specifically with women in mind.

Photo: flickr/Jeff Barton

As she explained to Slate, the minor gap in the toilet seat is to “allow women to wipe the perineal area after using the toilet without contacting the seat.”

Furthermore, Simick noted that the design of the toilet can also be of benefit to men, saying that the gap “eliminates an area that could be contaminated with urine,” but also “eliminates the user’s genital contact with the seat.”

So, if you didn’t know the history behind the gap in the public toilet, do you see it in a different light? Let us know!

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