The Quietest Room On Earth
It is 99.99 percent sound absorbent and holds the Guinness World Record for the world’s quietest place. The inside of the small room is lined on all six sides with deep, fiberglass wedges, a double wall of insulated steel, and foot-thick concrete. The room is so silent that the background noise measures negative decibels, -9.4 dBA. A typical quiet bedroom measures at 30 dBA