No matter where we are or how late it is, we are always exposed to some sort of noise - Be it the hum of the cars from the freeway or the tick-tock of an alarm clock by your bedside. So how would it feel to enter a room that is completely shut out from any external noise? Turns out that it is bearable, for only short spurts of time.

At least that's the verdict of the few peope who have been inside the Anechoic Chamber built by Orfield Laboratories in South Minneapolis. The room which has been certified as the 'world's quietest' by the Guiness World Records' is 99.99% sound absorbent thanks to its double insulated steel and concrete walls. Also blocking the sound are a series of 3.3-foot thick fiberglass accoustic wedges that are lined against the wall.

The main purpose of the room is allow corporations to test the sound quality of products and is used by companies ranging from motor bike manufacturer, Harley Davidson to consumer electronics maker, Whirlpool.

However, the laboratory occassionally also allows individuals to test how long they can last inside a darkened room where the only sound they can hear is their own heartbeat, pulse and even, ears! The longest stint so far has been a reporter, who lasted a full 45 minutes before he had to get out.

While this is the world's quietest chamber, NASA has a similar one that sounds even tougher - They ask the astronauts to step inside a water-filled tank situated in the room and then observe how long they can last before they start to hallucinate, and also if they can figure out how to work through it. While this may sound cruel, it is a crucial part of the training for space missions.

Resources: oddity central.com, dailymail.co.uk