Why are public toilet seats U-shaped? Here's the interesting reason

Ever noticed that the seats in most public toilets are different from what you have at home? It’s one of those things you hardly pay attention to until pointed out to you. The seats tend to be U-shaped with an opening in the front (giving it an incomplete look) while yours may be oval all round. And there’s a practical and hygienic reason for this distinction.

U-shaped seats

The open-front toilet seat was designed based on guidelines in the American Standard National Plumbing Code and was adopted by the International Association of Plumbing and Mechanical Officials (IAPMO). According to the code:

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.

But why? The reasoning behind this design is rooted in hygiene. An article in Reader's Digest explains that an open-front seat leaves less surface area for incidental contact with your nether regions.

For her

The drafters of the code also had women in mind while recommending this design. In an interview with The Slate, Lynne Simick, the senior director of code development at IAPMO explained that the gap in the seat is designed to

allow women to wipe the perineal area after using the toilet without contacting the seat [and for men] eliminates an area that could be contaminated with urine [and] eliminates the user’s genital contact with the seat.

The code used by the IAPMO applies in some form, to more than half the population of the U.S. and the world. To be sure, next time when you visit the washroom at a restaurant, gym, the mall or other public spaces, take a closer look at the seat.

Sources used:

Reader’s Digest: This Is Why Public Toilet Seats Are Shaped Like a U

The Slate: What’s That Thing? U-Shaped Toilet Seat Edition