Some farts are loud enough to register on the Richter scale. Others sneak out without making a peep, then 10 seconds later everyone in the room starts asking whether a sewer line ruptured.
These are the infamous silent but deadly farts, or SBDs.
The conventional wisdom is that quiet farts smell worse than loud ones. Butt is there actually science behind this theory, or have generations of DUDES simply confused correlation with ass causation?
Let’s investigate.
What Is a Silent But Deadly Fart?
A silent but deadly fart is exactly what it sounds (or rather, doesn’t sound) like: a fart that escapes your ass quietly but produces an unusually foul smell.
Unlike a booming butt trumpet, an SBD gives innocent bystanders no warning that a cloud of ass gas is headed their way. There’s no audible blast or opportunity to evacuate. One second you’re answering emails, and the next you’re wondering which coworker ate a dead animal for lunch.
The phrase has been around for decades, usually shortened to “SBD.” It also represents one of the fundamental laws of fart etiquette: The quieter the fart, the more suspicious everyone becomes.
But that raises an important scientific question: Why are some farts silent in the first place?
Why Are Some Farts Loud and Others Silent?
Fart noises are basically your butthole playing a wind instrument.
When gas exits your body, it passes through your anal sphincters—the rings of muscle that help control when gas and poop leave the premises. As gas pushes through, the surrounding tissue can vibrate and produce everything from a polite pfft to a thunderous cheek-clapper.
Several factors influence the volume.
More gas escaping at a higher velocity can create more vibration and therefore more noise. The tension of your sphincter matters too. A tighter opening can produce more vibration, while a more relaxed sphincter may allow gas to quietly sneak through.
A smaller amount of gas released slowly can also leave without much fanfare.
Bottom line: Fart volume mostly comes down to gas volume, velocity, and what your butthole is doing at the time.
Do Silent Farts Actually Smell Worse?
There’s no rule of human biology stating that quieter farts contain more stink.
The sound and smell of a fart are determined by different things: Sound depends heavily on how the gas exits your anus, while smell depends on what’s actually inside the gas.
That means you can theoretically fire off an enormous, window-rattling fart that barely smells at all. You can also silently release a tiny amount of sulfur-rich gas that makes everyone within 20 feet reconsider their relationship with you.
This may help explain why silent farts have earned their deadly reputation. By the time anyone detects it, the gas has already infiltrated the area and the perpetrator has had several seconds to establish plausible deniability.
Why Do Silent Farts Seem Deadlier?
Imagine somebody lets out a massive fart in the middle of a room.
Everyone knows exactly what happened, and the smell arrives afterward as supporting evidence.
Now imagine you're sitting quietly on an airplane when you suddenly smell rotten eggs.
You have no idea where it came from. You start looking around at 37 potential suspects while breathing through your shirt.
That element of surprise makes the smell feel more offensive.
SBDs also tend to spread before they're detected. A person can crop dust an office, grocery store, or airplane cabin and be long gone before the first victim gets a nostril full. It’s basically the fart equivalent of a hit-and-run.
There’s Nothing Deadlier Than a Shart Attack
Silent farts have a scary reputation, butt there’s nothing deadlier than a shart attack.
That’s when you expect a harmless little puff of gas and feel the unmistakable arrival of an unexpected passenger.
A wet fart can sneak up without warning, leaving you with a bigger problem than clearing the room. When gas turns into cargo, your only defense is DUDE Wipes.
The deadliest fart isn’t the one everyone smells. It’s the one you have to wipe.
