Para os interessados!
Tabela de decibeis
120 dBA Jet takeoff (200 feet)
110 dBA Construction Site Intolerable
100 dBA Shout (5 feet)
90 dBA Heavy truck (50 feet) Very noisy
80 dBA Urban street
70 dBA Automobile interior Noisy
60 dBA Normal conversation (3 feet)
50 dBA Office, classroom Moderate
40 dBA Living room
30 dBA Bedroom at night Quiet
20 dBA Broadcast studio
10 dBA Rustling leaves Barely audible
De qualquer forma, acho que até 21db é aceitável, acima disso, pensaria duas vezes.
Tuniq...