6. Source Intensity Level # of Times Greater Than TOH Threshold of Hearing0 dB10 0 Rustling Leaves10 dB10 1 Whisper20 dB10 2 Normal Conversation60 dB10 6 Busy Street Traffic70 dB10 7 Vacuum Cleaner80 dB10 8 Large Orchestra98 dB10 9.8 Walkman at Maximum Level100 dB10 Front Rows of Rock Concert110 dB10 11 Threshold of Pain130 dB10 13 Military Jet Takeoff140 dB10 14 Instant Perforation of Eardrum160 dB10 16

7. On the decibel scale, the smallest audible sound (the threshold of hearing) is 0 dB. A sound 10 times more powerful is 10 dB. A sound 100 times more powerful than near total silence is 20 dB A sound 1,000 times more powerful than near total silence is 30 dB.

8. A mosquito's buzz is often rated with a decibel rating of 40 dB. Normal conversation is often rated at 60 dB. How many times more intense is normal conversation compared to a mosquito's buzz ?