I read a letter to the editor about sound levels from wind turbines and different regulations about them in different states. Before a person should make comments about noise I strongly recommend that you buy a sound meter and listen to the differences between the regulations.
Also these sound waves must be tested at the home in all directions as shapes of trees, foliage, mountains, adjoining buildings and wind direction change dB’s received.
Insulation and window types also greatly affect indoor dB’s. Also different humidity levels affect dB’s received. So as you see it’s not just a simple one test tells all.
I managed a hotel in Baltimore MD years back and had a contract with a trucking company that used refrigerated trucks. I learned a good lesson about sound, sound waves, sound shapes and so on. I figured having the trucks with the refrigeration units running at night would be best placed facing one of our buildings, it would best serve the neighbors, WRONG. The noise bounced off our building and back toward the homes, at more dB’s than directly coming off the motors. Which was below allowable levels at the motors but not at the houses with the trucks facing toward my hotel. The shape of the bushes, trees and our building was causing a megaphone effect.
So in fact the dB’s at a home further away from the wind mill may get a higher level than ones closer. Also, to the letter writer, you didn’t state that the dB levels you gave were for readings at the home, inside the home, at the wind mill or 1 mile away, in what direction and which side of the mountain.
At 3 a.m. one big truck going down your road is a lot different than a constant buzz at the same sound levels and vibration all the time.
Steven Crowl, Fairfax