text: how to assess noise impact index? different methods for assessment of noise impact index painful:noise  150 db = rock music peak  140 db = firearms, air raid siren, jet engine  130 db = jackhammer  120 db = jet plane take-off, amplified rock music at 4-6 ft., car stereo,  band practice  extremely loud:  110 db = rock music, model airplane  106 db = timpani and bass drum rolls  100 db = snowmobile, chain saw, pneumatic drill  90 db = lawnmower, shop tools, truck traffic, subway  very loud:  80 db = alarm clock, busy street  70 db = busy traffic, vacuum cleaner  60 db = conversation, dishwasher  moderate:  50 db = moderate rainfall  40 db = quiet room  faint:  30 db = whisper, quiet library