How did you calculate 115+ decibles? Sounds like you greatly over estimated the sound.
"Your ears can endure 90 decibels of noise, such as a lawn mower, for about eight hours before damage occurs. For every 5 decibels above that, it takes only half as much time for damage to begin.
A noise at 95 decibels will hurt your ears in four hours. An arcade full of video games could cause damage in two hours. The average rock concert or stereo headset set at full blast (about 110 decibels) could damage your ears in a half hour."
http://www.fda.gov/fdac/reprints/ots_ears.html