[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Measuring Noise
David Staudacher wrote:
> On Thu, 18 Dec 1997 09:44:57 -0800,
> Chris England <email@example.com> wrote:
> >Sensitivity to sound levels can be estimated by using factors that
> >include both the sound level and the "white noise" character...
> >I have developed a rating method for noise based on this approach.
> Please elaborate. I'd like to hear more about your method. Does
> it yield a quantity based on some unit? Does it isolate a given set
> of conditions into various categories (i.e. minimal/moderate/extreme)?
> David Staudacher - firstname.lastname@example.org
> QUIET-LIST: Internet Mail List and Forum for discussion of Noise Pollution,
> Soundscape Awareness, and the Right to Quiet. Email: "email@example.com"
> To subscribe, email "firstname.lastname@example.org" with message "subscribe quiet-list".
> For info, send message "info quiet-list" to same.
Thank you for noting my message on rating noise. My friend Gertrude (b.
1914) advised me that people expect a simple numerical rating for just
about everything (thumbs up, four stars, etc.). On the quiet list,
there is no agreement that measurements are a valid means of rating
noise. If not measurements, then what?
In the 1970's, noise was taken more seriously. In the
anything-goes-for-commerce 1980's, these laws were left unfunded (at
least by the US Congress and by the State of California where I work).
The more serious noise work in the 1970's sometimes included "area
charts" in which the % of time at a dB level was plotted against the dB
level. With a little experience, this type of chart gives a very good
and very quick evaluation of the noise environment. Now, how to reduce
this to a rating?
I divide the chart into regions (but not simple vertical cuts), label
the regions from 1 to 6, and determine a rating. The "slope" of the
region determines the "white noise" character. It's a Master's thesis
to do the full justification, perhaps a Ph.D. thesis to assemble
confirming data. That's the problem. It takes a lot of time and effort
just to get agreement on a rating system.
The ratings I use are (1) very quiet, (2) quiet, (3) intermediate, (4)
transitional, (5) noisy, (6) very noisy. There is good agreement on the
qualitative ratings. People living in a 5-rated spot agree that it is
noisy; those living in a 3-rated spot agree that it is neither noisy or
quiet. One more thing. I separate day and night. The definitions of
"day" and "night" vary according to location. In Los Angeles, I like to
use 6:00 a.m. to 8:00 p.m. for day. This is based on the 24-hour noise
pattern in the area which is fully developed at 6:00 a.m. For the east
coast, perhaps 7:00 a.m. to 10:00 p.m. is better. In South America and
Europe, it would be different still.
QUIET-LIST: Internet Mail List and Forum for discussion of Noise Pollution,
Soundscape Awareness, and the Right to Quiet. Email: "email@example.com"
To subscribe, email "firstname.lastname@example.org" with message "subscribe quiet-list".
For info, send message "info quiet-list" to same.
Date Index |