This is the quietest place on earth and no one has lasted more than 45 minutes inside it

If you have ever imagined what space sounds like or a place so quiet that you can hear your organs or blood flowing through your body, you are lucky because a place like that exists. The anechoic (meaning echo-free) chamber at Orfield Laboratories in Minnesota is so deafeningly quiet that nobody can stand it for more than 45 minutes. According to the Smithsonian Magazine, the room is so silent that the background noise measured is negative decibels, -9.4 dBA. The chamber walls are made from 3ft of sound-proofing fiberglass wedges and insulated steel and concrete, and the floors are covered in a semi-permeable, trampoline-like mesh to absorb any possible sound. 

Steven Orfield, the lab's founder, told Hearing Aid Know: “We challenge people to sit in the chamber in the dark – one person stayed in there for 45 minutes. When it’s quiet, ears will adapt. The quieter the room, the more things you hear. You’ll hear your heart beating, sometimes you can hear your lungs, hear your stomach gurgling loudly. In the anechoic chamber, you become the sound." As reported by the BBC, sensory deprivation makes the room extremely disorienting, causing people to have difficulty orienting themselves and standing. "How you orient yourself is through sounds you hear when you walk. In the anechoic chamber, you don't have any cues," Orfield told the Daily Mail. "You take away the perceptual cues that allow you to balance and maneuver. If you're in there for half an hour, you have to be in a chair."

While it may not sound like a fun place to spend your next vacation, businesses and astronauts use the chamber extensively. Companies use the chamber to test their products, such as washing machines, refrigerators, and Harley-Davidson motorcycles, and NASA uses a similar room to perform stress tests on astronauts. The chamber is currently registered in the Guinness World Record as the world's quietest place, a title it claimed in 2015, and has since become a tourist attraction. "We get thousands of requests. Members of the public visit from around the world almost every week, and they are just about always excited by the experience. There is no skeptical reaction, as this is simply a bodily experience, and there's nothing to learn or believe," wrote Steve Orfield, reported CNN. 

Orfield says the experience is somewhat influenced by a place where one was immediately before entering the chamber because coming from a loud environment makes it harder to adapt to the quietness. The quality of your hearing also counts: the older you are, the harder it is to comprehend the silence, reported CNN. He also recommends turning off the lights. "Most of the experiences of sensory deprivation, include turning off all lighting, so that you are in aural and visual quiet, with no sensory noise. Under this circumstance, walking around the interior will make most people lose their balance after a short while."

Since the chamber at Orfield Labs is the only accredited lab in the United States, it attracts an even wider audience. Moreover, there is no "world record" for time spent in the chamber by a person, and such challenges are not encouraged, although Orfield said he receives many requests from people who want to "beat the record." He adds, "I've spent about 45 minutes in the chamber, and since I have a mechanical heart valve, I can always hear it."

Hundraj Gopal, a speech and hearing scientist and the principal designer of the anechoic chamber at Microsoft, wrote in an email saying, "The longest continuous time anyone has spent inside the chamber is about 55 minutes, but I have noticed that there are several folks who can stay inside for 30 minutes or so. But others have asked to go out within the first few seconds."