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by Daniel Fink, MD, Chair, The Quiet Coalition

Humans, our primate ancestors, and generations of vertebrates, invertebrates, and simpler forms of life evolved in quiet. Except for a few loud noises–thunderstorms, earthquakes, waterfalls, loud animal calls, and birds gathering at dawn or dusk–quiet rules.

The National Park Service noise map shows that, as do my own sound pressure level measurements in remote locations. I have measured nighttime sound levels near 30 A-weighted decibels (dBA)* at at Lake Vyrny in Wales, in remote parts of the Alps, and in Wupatki National Park in Sri Lanka. And just recently I did the same in the remote Huab Reserve in Namibia:

The prior measurements were made using the Faber app on my iPhone 6, but this one was taken on the NIOSH sound meter app.

Since I last wrote about nature’s quiet, I have learned that the Federal Aviation Administration thinks that 65 dBA DNL (day night sound level) is suitable for human residential use. But the Environmental Protection Agency determined that only 45 decibels (dB) is safe for indoor noise exposure and 55 dB for outdoor noise exposure. Those safe noise levels were determined by EPA as specifically mandated by Congress in the Noise Control Act of 1972.

If nature is quiet, by definition loud noise is unnatural. It’s also unhealthy.

And as confirmed by my latest measurements, nature is still quiet.

*A-weighting adjusts sound measurements to reflect the frequencies heard in human speech.