Going to the bathroom is usually a simple routine for most adults. We do our business and don’t give it another thought. But a recent viral video has shed light on a surprising concern: flushing the toilet with the lid up. Turns out, what happens in the toilet can very much end up outside of it, leading to an unexpected (and unsettling) hygiene issue.
What Really Happens When a Toilet Flushes
Researchers at the University of Colorado Boulder made a startling discovery: flushing a commercial toilet creates a cloud of droplets and aerosol particles that can shoot over 5 feet into the air! Although this tiny mist is invisible to the naked eye, the researchers captured it with green lasers, making the droplets appear like neon green confetti. Take solace in the fact that their toilet contained only clean water, but think about what might be in the usual toilet bowl!
This study, published in the journal Scientific Reports, examined how particles are dispersed during flushing. Although they didn’t test the actual particles that might be spewed into the bathroom, it’s enough to know that flushing can send unsavory droplets everywhere.
“We all were astonished,” said John Crimaldi, the study’s lead author and a professor of hydrology who specializes in fluid mechanics. “I said, ‘Oh, my God — that’s what happens?”
Why You Should Always Flush With the Toilet Lid Down
Researcher Karl Linden, an environmental engineer, helped initiate this study to explore ways to use ultraviolet-light-based disinfectants. “Where do we get exposed to viruses, and where do we get exposed to pathogens?” Linden asked. “One thought I had was, ‘Well, what’s happening in toilets?’”
This is especially relevant for commercial toilets in public restrooms, which often lack lids. These toilets use a flushometer-style valve, relying on pressure to clear the bowl. The result is a higher, invisible mist that lingers in the air.
“I have an intuitive sense that the presence of solids might exacerbate the problem because there are just additional things for the water to impinge on and to create more opportunities for this energetic mixing of fluids,” Crimaldi noted.
Like the study suggests, we should strive for better methods of waste disposal in the future. Until then, close that toilet lid when you flush! This simple act isn’t always possible in public restrooms, but it highlights the importance of other bathroom etiquettes to stay hygienic.
Don’t Linger in Public Bathrooms
Public bathrooms aren’t the place to hang out or chat. If you see someone while washing your hands, a nod or polite smile is enough. Try to keep a good distance at urinals and avoid hovering in front of occupied stalls, especially those with spaces allowing for unfortunate peeks inside.
Don’t Bother a Locked Door
If the door is locked, it means someone is using the bathroom. Don’t keep knocking or trying the doorknob. You can knock once politely to show you’re waiting, but then step back. No one likes to feel rushed during their time in the bathroom.
Lock the Door
Conversely, always lock the door behind you. This signals that the bathroom is occupied and avoids any awkward moments for everyone involved. Even if you’re comfortable with someone accidentally walking in, they probably aren’t!
Only Flush Toilet-Friendly Items
Toilets are designed for human waste and a reasonable amount of toilet paper—nothing else. Don’t flush sanitary pads, tampons, diapers, wet wipes, plastic items, and other trash. These items can cause serious clogging and other plumbing issues down the line.
Change the Toilet Paper Roll
Always leave the bathroom prepared for the next person. Replace the toilet paper if it runs out. While you might not be able to do this in public restrooms, at least warn the next person waiting for the stall if the roll is empty.
Wash Your Hands
Washing your hands after using the bathroom is a basic yet crucial habit. As the study shows, bathrooms can be laden with germ-filled aerosols and bacteria. Don’t take any of that outside with you. Clean hands are a simple way to prevent the spread of disease.
