Читать книгу Sleep: The secret to sleeping well and waking refreshed - Prof. Idzikowski Chris - Страница 85

People can be awoken by neutral sounds louder than 45 decibels (dB), the equivalent to someone talking quietly (a lawnmower is around 105dB and the threshold for injury to the ear is around 140dB). However, sounds as low as 20dB (below the hearing threshold) can prevent you from falling asleep.

Conversely, continuous background sounds can be soporific and it seems that sounds even below 20dB can induce sleepiness – a clear danger for lorry and train drivers. Irregular high-frequency noise can have the opposite effect and be intrusive.