# Sound: aim for ~35 dB, and hate inconsistency

Urban bedrooms sit at 60–70 dB. It's the *change* in sound that wakes you.



## Takeaways

- Measure your bedroom (Lab → Noise meter).

- Sound machine < 40 dB, away from bed.

- Turn podcasts off before lights-out.



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.



## Sources

- Night noise guidelines for Europe (World Health Organization Regional Office for Europe, 2009)

- Auditory and non-auditory effects of noise on health (Basner M, Babisch W, Davis A, et al., 2014)

- Noise as a sleep aid: a systematic review (Riedy SM, Smith MG, Rocha S, Basner M, 2021)

- Environmental noise and sleep disturbances: a threat to health? (Halperin D, 2014)

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Educational summary of published research, not medical advice. Screening scores are not diagnoses. If a score is elevated or you feel unwell, talk to a clinician.

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