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Speaker 1: Brain with today's question. What is a decibel and how
Speaker 1: is it measured? The decibel, abbreviated dB, is the unit
Speaker 1: used to measure the intensity of a sound. The decibel
Speaker 1: scale is a little odd because the human ear is
Speaker 1: incredibly sensitive. Your ears can hear everything from your fingertip
Speaker 1: lightly brushing over your skin to a loud jet engine.
Speaker 1: In terms of power, the sound of the jet engine
Speaker 1: is about one trillion times more powerful than the smallest
Speaker 1: audible sound. That's a huge difference on the decibel scale.
Speaker 1: The smallest audible sound near total silence is zero dB.
Speaker 1: A sound ten times more powerful as ten dB. A
Speaker 1: sound a hundred times more powerful is twenty d B.
Speaker 1: A sound a thousand times more powerful than total silence
Speaker 1: is thirty d B. Here are some common sounds and
Speaker 1: their decibel ratings. A whisper is about fiften dB. Normal
Speaker 1: conversation is around sixty d B. A lawnmower is up
Speaker 1: near ninety. A car horn is a hundred dB, a
Speaker 1: rock concert or a jet engine is a hundred and
Speaker 1: twenty d B, and a gunshot or a firecracker is
Speaker 1: around a hundred and forty d B. These are the
Speaker 1: levels when standing near the source of the sound. You
Speaker 1: know from your own experience that distance affects the intensity
Speaker 1: of sound. If you're far away, the power is greatly diminished.
Speaker 1: Any sound above eight five dB can cause hearing loss,
Speaker 1: and the loss is related both to the power of
Speaker 1: the sound as well as the length of exposure. Sure
Speaker 1: you know that you're listening to an eight five dB
Speaker 1: sound If you have to raise your voice to be
Speaker 1: heard by somebody else, eight hours of nine d dB
Speaker 1: sound can cause damage to your ears. Any exposure to
Speaker 1: a hundred and forty dB sound causes immediate damage and
Speaker 1: may cause actual pain. Do you have any ideas or
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