Why are ladies room lines longer than those at men's rooms?
Any woman who has ever been to a public bathroom knows to expect a long queue at the ladies room. There may even be some who have ducked into the inexplicably empty men's room to avoid waiting in a long queue. And who can blame them? Imagine leaving a movie theater after drinking up a large cup of iced tea, needing desperately to pee, then coming upon a long line of women at the bathroom. Bladders aren't made of cast iron, so long waiting times can be tough for some. But why are queues at the ladies room frequently so long, while lines at the men's room aren't as long or are even nonexistent?
Two queueing theorists (which is apparently a thing) have found three explanations for long lines at the ladies room. Not just that, they've also found a possible solution to this problem.
The first explanation is that women's public bathrooms don't have as many toilets as men's public bathrooms. Ladies rooms have toilet cabins for privacy, and these cabins take up more space than urinals. Thus, ladies and men's rooms of equal size don't accommodate the same number of facilities. The researchers found that men's rooms typically have 20 to 30% more usable facilities—toilets and urinals—than ladies rooms do.
The second explanation, meanwhile, isn't really a surprise. Women simply spend more time in the bathroom than men—something that we all probably know. In fact, the researchers found that women spend one and a half to two times as much time in the bathroom as men. Women spend more time in the bathroom simply because there's more to do. They have to open and close the toilet cabin door, and removing clothes in order to urinate is more complicated than simply undoing a zipper. Also, women need to clean the toilet seat for hygiene before use.
The third explanation situates the other two in context. Simply having fewer toilets and spending more time in the bathroom won't lead to long ladies room lines. However, if it's a busy time in the day, and there is heavier foot traffic in the bathroom, then more women will be using the facilities. Thus, the combination of fewer toilets, time spent in the bathroom, and the number of women in the bathroom leads to longer queues.
To address this problem, researchers used different layouts and tested them in scenarios with light and heavy foot traffic. They found that the best layout is one in which ladies rooms have one and half to two times as many toilets as men's rooms. However, the researchers also found a solution in which ladies and men's rooms aren't separate.
The researchers suggest that having unisex bathrooms is the way to go. Toilet cabins are available for both men and women, and men also have the option of using urinals. Unisex bathrooms are more efficient, the researchers say, and long ladies room lines can be a distant memory.
Get weekly science updates in your inbox!