Dubbed the “World’s Quietest Room” by the Guinness World Records, the anechoic (non-echoing) chamber at Orfield Labs in Minneapolis is used as a facility to test the sound-emitting qualities of various products. The room has been measured at -9.4 decibels (the average conversation is about 60 decibels) and exists as a thick-walled space suspended within the larger building and lined with sound-absorbing panels and a mesh-like floor that prevent noises from reflecting off the room’s surfaces. The resulting deadening effect has been described as disconcerting, where visitors can hear their own heartbeat or even the sound of a mobile phone display.