How did public bathrooms get to be separated by sex in the first place? May 26, 2016 10.03pm EDT A 19th-century photograph of a women’s restroom in a Pittsburgh factory. Author provided.

…In fact, laws in the U.S. did not even address the issue of separating public restrooms by sex until the end of the 19th century, when Massachusetts became the first state to enact such a statute. By 1920, over 40 states had adopted similar legislation requiring that public restrooms be separated by sex.

So why did states in the U.S. begin passing such laws?

[…]

Nonetheless, American culture didn’t abandon the separate spheres ideology, and most moves by women outside the domestic sphere were viewed with suspicion and concern. By the middle of the century, scientists set their sights on reaffirming the ideology by undertaking research to prove that the female body was inherently weaker than the male body.

Armed with such “scientific” facts (now understood as merely bolstering political views against the emergent women’s rights movement), legislators and other policymakers began enacting laws aimed at protecting “weaker” women in the workplace. Examples included laws that limited women’s work hours, laws that required a rest period for women during the work day or seats at their work stations, and laws that prohibited women from taking certain jobs and assignments considered dangerous.

Midcentury regulators also adopted architectural solutions to “protect” women who ventured outside the home.

Architects and other planners began to cordon off various public spaces for the exclusive use of women. For example, a separate ladies’ reading room – with furnishings that resembled those of a private home – became an accepted part of American public library design. And in the 1840s, American railroads began designating a “ladies’ car” for the exclusive use of women and their male escorts. By the end of the 19th century, women-only parlor spaces had been created in other establishments, including photography studios, hotels, banks and department stores.

It was in this spirit that legislators enacted the first laws requiring that factory restrooms be separated by sex.

[…]

Finally, Victorian values that stressed the importance of privacy and modesty were subjected to special challenge in factories, where women worked side by side with men, often sharing the same single-user restrooms.

It was the confluence of these anxieties that led legislators in Massachusetts and other states to enact the first laws requiring that factory restrooms be sex-separated. Despite the ubiquitious presence of women in the public realm, the spirit of the early century separate spheres ideology was clearly reflected in this legislation.

Understanding that “inherently weaker” women could not be forced back into the home, legislators opted instead to create a protective, home-like haven in the workplace for women by requiring separate restrooms, along with separate dressing rooms and resting rooms for women.

Thus the historical justifications for the first laws in the United States requiring that public restrooms be sex-separated were not based on some notion that men’s and women’s restrooms were “separate but equal” – a gender-neutral policy that simply reflected anatomical differences.

Rather, these laws were adopted as a way to further early 19th century moral ideology that dictated the appropriate role and place for women in society.

The whole article is very good, click over and read.