Determining the sound level of a leaf blower

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The sound level of a leaf blower rated at 75dB is typically measured at a distance of 50 feet, as indicated by a manufacturer's lobbyist. Sound intensity increases as one gets closer to the source, with a doubling of distance resulting in a decrease of approximately 6 dB. This means that at closer ranges, the perceived noise level can be significantly higher. The discussion highlights the importance of understanding measurement distances when evaluating noise levels. Accurate sound level assessments are crucial for compliance with noise regulations and for user comfort.
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Homework Statement
How does one determine the dB of a leaf blower.
Relevant Equations
db = 10log(p1/p2)
I have a leaf blower that states the sound level is 75dB. My question is, at what distance is this measured. It seems that as you get closer to the source, the dB number will increase drastically. If I double the distance from the source, then the power should go down by a factor of four or 6 db. Is this correct?
 
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You are correct. Can you post a link for the product?
If not stated, I would take it as the expected distance from the device to the operator's ears.

Update: found this
https://www.nonoise.org/quietnet/cqs/leafblow.htm
"The average blower measures 70-75 dB at 50 feet according to a manufacturer's lobbyist"
So maybe 50 feet is standard.
 
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