Sound and Noise Distance

[nuke11]

I was looking for a chart or formula that would help figure out how loud something would be over a distance, so I had a look around on the internet and found this that should help in the game.

In the world of TMP loud sounds will be uncommon in most areas of the country so any noise will be unusual. So the following formulas can be used to tell how loud a noise will be at a certain distance or used to figure out how loud it was at the source (might not be that useful but interesting). Variables to also consider atmospheric conditions and the environment around the observer. High frequencies are absorbed faster than low frequencies by water vapor and dust in the air. All sound is measured in decibels (dB).

If you know or have an educated guess of the sound level from source you can use the following;

Sound source - (20log(distance in m's) + 11) = sound level at observer dB (outdoors)

If you know the sound level and distance of source from the observed level from source:

(20log(distance from source) + 11) + level heard = sound level at the source

Example: you are 1060 m from a road, you hear a sound level of 20 dB where you are.

(20log(1060) + 11) + 20 = 91.5 dB (at roadway)


There are a number of websites that list common sound levels for everyday objects and sounds.

I'll work on an spreadsheet that helps calculate sound levels at different distances.