Silence is often said to be golden. But the world’s quietest room is so quiet that it could drive people who spend more than an hour inside crazy.
The silence there is said to be so disorientating to the human senses that it can induce short-term psychotic episodes and hallucinations.
The anechoic chamber at Orfield Laboratories in Minneapolis, USA, is designed to enable accurate measurements of the sound levels produced by various test items, with extreme soundproof measures taken to stop sound coming in or out.
It comprises a large masonry and concrete chamber lined with 10.5-cm-thick steel plates, within which there is another, smaller steel chamber supported on vibration absorbing springs. The interior of this space is lined with a layer of heavy insulation covered with glass-fibre wedges that extend 85 cm into the space.
In 2021, it broke the world record held by Microsoft to become the quietest place on Earth, recording a sound of -24.9 decibels.
To put that in context, a regular whisper would be at around 30 decibels whilst a person breathing normally would be about 10.
The room took around two years to build and sits beneath six concreate layers that work to block out sounds from the outside world reaching it.
Were a jumbo jet to take off outside, the noise would be unlikely to penetrate the thick, soundproof walls.
Company founder, Steven Orfield, told MailOnline: “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.”
It is extremely rare for a human being to experience 0 decibels, never mind quietness below this level.
Things that human beings consider quiet are closer to 20-40 decibels such as being in a quiet library or being able to hear your own heartbeat.
Exposure to quietness below 0 decibels can therefore be extremely difficult for the other senses to adjust to.
Peter Suedfeld, a psychologist at the University of British Columbia who has studied sensory deprivation, explains the impact a prolonged period of time in the room could have.
He said: “We are used to every sound producing a small echo from the world around us. In these chambers, there is just dead sound. It is just like going into a dark room, at first you cannot see anything but over time your eyes adapt.”