The scale at left shows sound-level measurements for common woodworking machines. The measurements were taken at head height while the machines cut wood. The sound-level meter measured the intensity of sound in dec/-bets (dB) and was designed to respond to sound much as our cars do. A sound level of about 85 dB is considered to be the threshold for possible hearing loss. Hearing protectors arc recommended at this level.
To compare the readings, understand that the decibel scale is logarithmic. That's a mathematical way of compressing a wide range of sound intensities into a more convenient numerical range from zero dB (the threshold of hearing) to above 140 dB (the threshold of pain). A logarithmic scale gets confusing because you can't directly compare decibel values the way you can compare values on a linear scale.
If the intensity of any sound level on the decibel scale is doubled, it increases by three decibels. That means two tablesaws running at 100 dB each would measure 103 dB, not 200 dB. Also, any changc of 10 dB represents a tenfold difference in intensity. Thus, 90 dB is 10 times more intense than 80 dB and 10 times less intense than 100 dB.
Our ears are a poor judge of actual sound intensity. For example, we perceive a 10-dB increase to be about twice as loud, when it's really 10 times as intense.—D.S.
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There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.