Ready to learn a little about the quietest places on earth? This is so quiet that people are unable to spend extended periods of time in them without going insane, literally.
What does Anechoic mean?
Anechoic means non-reflective and echo free. An Anechoic Chamber completely absorbs echoes, reflections of electromagnetic and/or sound waves.
The foam absorbs everything. These rooms are used to measure the amount of sound that comes from things as small as phone processors, and much more. The background noise average measurement is -9.4 dBA. It's hard to comprehend a room with negative noise, but this is it.
The Human Side
The human ear can detect sounds above 0dBA. This makes people in such a chamber perceive the surroundings as devoid of sound. More terrifying than it would seem.
Human ears adjust to surroundings. This is how people can hear each other at clubs with loud music and still talk. When the background noise is negative human ears start to look for sounds to attach to. People often begin to hear their heartbeats, lungs, stomach gurgling, blood in the neck and brain, etc. This is where it gets so intense that those sound "loud." Often people lose sense of balance, and have inability to stand or orient themselves since their ears don't have reflections to help figure out where they are.
"If you are there for 30 minutes, you have to have a chair."
Possibly the longest time anyone has spent in the chamber closed and alone was around 45 minutes. Not that long after all!
NASA
NASA actually uses these chambers to help astronauts adjust to the silence they might experience in space.
