wookie (02/23/83)
PERMISSIBLE NOISE EXPOSURES
HoSoun Level dB (A)
8 90
6 92
4 95
3 97
2 100
1.5 102
1 105
0.5 110
0.25< 115
>From part 1910.95 "Occupational Noise Exposure" (Dept. of Labor) of the Code
of Federal Regulations, Chap XVII of Title 29
See also Guidelines to the Dept of Labors Occupational Noise Standards,
Bulletin 334, GPO: 1971 O-484-782(3).
I have worked with sound reinforcement equipment at rock concerts (with
ear protection in place!!!!) and have measured levels in excess of 120dB
measured three feet in front of the speakers. People would come right
up to the front of the speaker (one foot) and listen for quite a while.
I was always amazed at this and wonder why hearing protection isn't of
more concern. I am glad to see there are people out there concerned
about this problem and I would suggest that you buy or rent a Sound Level
Meter such as the General Radio type 1565-B and go to the gym where your
children are practicing and see for yourself what levels are involved.
The table above shows what the government allows and we know that is
probably too much exposure anyway!
Too loud noises will cause permanent nerve damage to the delecate tissues
in the ear so protect what you have!
Keith Bauer
White Tiger Racing
Bell Labs Murray Hillwookie (02/23/83)
The column labels in my previous message were fowled up. The first column is Hours of exposure and the second column is dB (A). That is decibels measured using an A weighting scale which favors the higher frequencies which causes more damage. Keith Bauer White Tiger Racing Bell Labs Murray Hill