Whenever there's a question about toilets, I head for the Toilet
Museum. I'm not fooling. The Internet has just about everything,
including a website devoted to toilet lore.
Without further ado, here's the Toilet Museum's answer to the question
about public toilet seats:
"Why do public toilet seats have a break in the front?
This question is, by far, the most frequently asked question received
by the museum. Toilet seats with a 'break' in the front are called
'open front' seats. The open front toilet seats afford the users more
sanitary conditions and a greater sense of comfort than their
residential closed-front cousins. The reason that the open front
toilet seats are so widely used in the U.S. is due to section 409.2.2
of the Uniform Plumbing Code. The Uniform Plumbing Code is written and
maintained by the International Association of Plumbing and Mechanical
Officials. The code has been adapted into law, in whole or part, by
most of the United States."
Another great source of info about toilets (and almost everything
else) is the archives of The Straight Dope:
"Public toilets are designed the way they are for the obvious reason:
men are pigs. In particular, they splash, and when they're out of the
house and away from the restraining influence of their families, they
splash even more--and they don't wipe up. The relevant male apparatus
being in the front, this makes the front of the toilet seat
(particularly the underside) pretty gross--or rather, it would make it
gross, if toilet-seat makers hadn't been shrewd enough to head the
problem off at the pass. Who the unsung genius was who started this
practice we may never know, but it's now embodied in industry
The Straight Dope Archives
So it seems that the Uniform Plumbing Code has decreed that, since men
are not very specific when they urinate, all toilet seats, in both
men's and women's facilities, shall be U-shaped rather than O-shaped,
to facilitate cleanup. Apparently the Uniform Plumbing Code has not
caught on to the fact that the plumbing of human bodies is not
uniform, but comes in two distinctly different configurations. ;-)
Sure enough, here it is in the Uniform Plumbing Code (this text is
from Missouri, but the code is pretty much the same in all of the
"409.2.1 All water closet seats shall be of smooth non-absorbent
409.2.2 All water closet seats, except those within a single and
multifamily dwelling unit, shall be of the open front type.
409.2.3 Water closet seats shall be properly sized for the water
closet bowl type."
Search terms used:
"public toilet seats"
"uniform plumbing code"
Thanks for asking an interesting question! If anything is unclear, or
if a link does not function, please request clarification; I'll be
glad to offer further assistance before you rate my answer.