The human voice ranges from a whisper, 20 decibels, to the loudest shout ever recorded at 121 decibels, which is equivalent to the volume of noise produced by a chainsaw or leaf blower. This record was set by a teacher, Annalisa Flanagan in 2010.
A normal speaking voice is approximately 70 decibels and an average shout about 88 decibels. Any sound over 120 decibels is painful for humans, and sounds over 150 can cause the eardrum to rupture. To determine the potential for hearing damage, the loudness, in decibels, is weighed against the time of exposure. For instance, the sound of a lawn mower doesn't present a risk of hearing loss unless someone were continuously exposed to the sound for over eight hours.