What is the world's quietest room record and how is it measured?

The world's quietest room record is held by Microsoft's anechoic chamber in Redmond, Washington, with a measured sound level of -20.35 decibels. This room is designed to absorb sound waves and minimize external noise, creating an extremely quiet environment. The measurement of sound levels in the room is done using specialized equipment called a sound level meter, which detects and quantifies the intensity of sound waves present in the room.