>30 dB
background noise in all monitored bedrooms exceeded recommended sleep levels
dB (decibels) is the unit of sound level
The equivalent continuous sound pressure level in all monitored bedrooms was above 30 dB
Across all 41 participants' bedrooms monitored in Cassino, Italy, the nighttime LAeq was consistently above 30 dB before the eco-feedback intervention. This universal exceedance of the 30 dB threshold suggests that acoustic conditions in these bedrooms were not conducive to undisturbed sleep, compounding the already poor indoor air quality conditions observed in the same spaces.
94% of the volunteers slept in bedrooms with a median indoor CO2 concentration >800 ppm, the equivalent continuous sound pressure level was always >30 dB, and the self-reported sleep quality conditions were characteristic of disrupted sleep or intermediate sleep disturbance
Related findings
59.0 dBA
average PACU noise level nearly 20 dB above WHO recommendation
Mean sound level in the PACU was 59.0 dBA, far exceeding the WHO-recommended 40 dBA
Arnaud Weynants et al., 2024, Journal of PeriAnesthesia Nursing
+9.59 arousals
more sleep arousals under ICU noise conditions than baseline
ICU noise significantly increases the number of sleep arousals in healthy subjects
Sandra Horsten et al., 2017, British Journal of Anaesthesia
-6.08%
lower heart rate with combined audio-visual nature stimuli at 26°C
Combined audio-visual natural stimuli reduced heart rate by 6.08% at 26°C
Min Wang et al., 2026, Buildings
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