The World Record for Silence: –24.9 dBA

Silence now has a new world record. In 2021, Orfield Laboratories, based in Minneapolis, officially earned the Guinness World Record for the quietest room, with a background noise level measured at –24.9 dBA. This number is so low, it challenges not only our hearing but our very perception of sound itself.

A certified technical feat

This record is recognized by the Guinness World Records. To achieve it, the chamber was built with ultra-absorbent materials, reinforced concrete walls nearly a meter thick, and complete isolation from the outside building. The result? No sound escapes, and none returns. The space is acoustically “dead.”

A history of increasing silence

Inside the room, silence reigns—so deep that the background noise is measured in negative decibels, meaning it's below the human hearing threshold. In 2004, the chamber registered –9.4 dBA (a scale weighted to reflect human hearing). After improvements in 2012, it reached –13 dBA. But in 2015, Microsoft briefly stole the title with a chamber in Redmond, Washington measuring –20.35 dBA. Orfield Laboratories reclaimed the top spot in November 2021 with a stunning –24.9 dBA.

What does –24.9 dBA mean?

The dBA scale is adjusted to the human ear's sensitivity. Zero dBA represents the average threshold of hearing. A level of –24.9 dBA means the ambient noise is lower than what most people can perceive—only detectable with extremely sensitive laboratory microphones.

Physiological effects of extreme silence

This absolute silence comes with surprising side effects. In this chamber, people can hear their heartbeat, joints moving, and even their eyes blinking. Most visitors can't last more than a few minutes. The brain, deprived of external sound cues, may respond with balance disturbances or anxiety.

A tool for research and innovation

This record isn't just symbolic. Such chambers are used to test low-noise audio devices, conduct neuroscience research, and simulate conditions like those in space. Microsoft’s chamber at –20.35 dBA, for instance, is used for audio hardware development and product validation.

The growing quest for silence

The –24.9 dBA record shows just how far humans can go in controlling sound environments. It also reveals our vulnerability to the complete absence of noise, reminding us that silence isn’t empty—it’s another kind of sensory experience. A stunning blend of engineering and perception.