Question about acceptable noise/vibration levels in workplace

[Daniel Levitin <levitin@xxxxxxxxxxxxxxxxxx>]

Dear list,

Al Bregman and I are experiencing problems with vibration and noise
in our building at McGill.  The problems have arisen gradually, and
appear to be the result of damaged damping and isolating systems on
ventilation machinery that is on the floor directly above our
workspaces.  We have been asked to supply our Facilities maintenance
people with exact figures on what we consider acceptable levels based
on "industry norms" and "standard practice."

We took the following readings with a hand-held, relatively
inexpensive decibel meter:

Location                       A-weighting  B-weighting     C-weighting
Bregman's office             52                62                    74
Bregman's lab                  51                62                    70
Levitin's office               46                57                    68

Subjectively, these workspaces seem to us to be too loud for comfort.
In comparison, a room that seems more comfortable, our department
mail room, reads as follows:

Psych dept mail room      < 40              48                    60

In addition to this measurable (and audible) noise, there is a
serious vibration problem that we are not capturing on our decibel
meter, I suspect because the small diaphragm size of the microphone
on the meter doesn't accurately capture low frequencies.  But a 6 oz.
glass of water on my desk shows the vibration with "waves" inside the
glass with an oscillatory frequency of roughly 25 Hz.

Naturally, we can tolerate slightly more noise and vibration in our
offices than in the lab where we do experiments and prepare stimuli
for psychoacoustic experiments.

Can anyone provide data (and a citation) on industry standards for
noise and vibration in a typical office space and a typical
acoustical lab?  Would any of you be willing to take measurements in
your offices and labs and let us know what they are as a first step
toward understanding what is reasonable and normal?

Thank you very much,


Dan levitin


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Daniel J. Levitin                                Phone: (514) 398-8263
Assistant Professor                        FAX:     (514) 398-4896
Department of Psychology
Associate Member of the Faculty of Music

Mailing Address:
McGill University
Stewart Biology Building
1205 Ave. Dr. Penfield
Montreal, PQ    H3A 1B1
CANADA

email: levitin@ego.psych.mcgill.ca
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