Exposure to Loud Sounds — How Many Decibels Sound Drops Per Foot?

[Seawater7]

Can anyone tell me how many decibles drop per foot? I was exposed to a very loud muffler at about 30 ft. And now my tinnitus is louder then it has been in years.

 

[sjtinguy]

dB levels drop 6 dB as you double the distance... so if the sound was 100db at 10 feet, it would be 94 at 20 feet, 88 at 40 feet, 82 at 80 feet, etc. I hope your tinnitus goes down soon

 

[Seawater7]

Thank you for the reply, i still don't understand the formula though, so what would 140 db be at 30ft away?

Do you think that could cause hearing damage or does sound also disperse when outside and enter the ear less..

Thank you

 

[Vincent R]

Thank you for the reply, i still don't understand the formula though, so what would 140 db be at 30ft away?

Do you think that could cause hearing damage or does sound also disperse when outside and enter the ear less..

Thank you

2m = -6db
4 m= -12 db
8m = -18 db
16m = - 24 db
32 m = -30 db

Etc.

 

[Seawater7]

Thank you, i am guessing loud sports car exausts can't cause hearing damage then unless very close to it.

 

[sjtinguy]

2m = -6db
4 m= -12 db
8m = -18 db
16m = - 24 db
32 m = -30 db

Etc.

this is true if you are measuring the original volume at 1m from the source.

 

[GregCA]

Thank you for the reply, i still don't understand the formula though

Look here.

 

[Alue]

You have to know at what distance the initial measurement was made.

 

[Seawater7]

Is there an average distance when people measure the sound level of something?