Here's a chart of some cool decibel levels:

Jet engine - close up  
 150Snare drums played hard at 6 inches away
Trumpet peaks at 5 inches away
 140Rock singer screaming in microphone (lips on mic)
Threshold of pain  
Pneumatic (jack) hammer Cymbal crash
Planes on airport runway120 
  Fender guitar amplifier, full volume 10 inches away
Power tools110 
Subway (not the sandwich shop)100 
Heavy truck traffic  
 80Typical home stereo listening level
Acoustic guitar, played with finger at 1 foot away
Average factory  
Busy street Small orchestra
 60Conversational speech at 1 foot away
Average office noise50 
Quiet conversation40 
Quiet office30 
Quiet living room20 
 10Quiet recording studio
 0Threshold of hearing for healthy youths