Sound: aim for ~35 dB, and hate inconsistency
Urban bedrooms sit at 60–70 dB. It's the *change* in sound that wakes you.
Rural night noise sits around 35 dB; urban baselines are 60–70 dB. WHO recommends outdoor night noise under 40 dB, with sleep effects starting around 30–35 dB indoors. Sound matters as much as, if not more than, any other factor — noise fragments sleep and raises cardiovascular risk even when you don't consciously wake.
The big issue is inconsistency: a dog getting up, a window creaking, a car passing, an air conditioner cycling. A sound machine masks these — but most people put it too loud (default 40–50 dB) and too close. The evidence for white noise itself is weak; keep it under 40 dB, especially for children.
Podcasts, TV and audiobooks running through the night are a common cognitive switch-off strategy. It's understandable — but it will never lead to your best sleep. Better: find a down-regulation method that gives you the same switch without disrupting the night.
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Sound: aim for ~35 dB, and hate inconsistency?
Urban bedrooms sit at 60–70 dB. It's the *change* in sound that wakes you.
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