Oscar - I will take some pot shots at my experience.
The wire resistors are these large units where the wire coils are in a
frame.
The whole assembly was covered with dust.
As I dumped 10-20KW into these loads they did heat up and cause some fumes.
I do have alergies and so maybe there was somthing to this vapor exposure.
Another issue was my concern about the safety of the loads.
This was a lab where we tested motor starters till failure.
If you've experienced enough phase to phase faults at 480 from a stiff
utility feed it will make you nervous.
So another issue was my paranoia of the loads.
But I was typically wrapped up in seeing if my code changes were working.
I am just pointing out how there are so many variables to this event.
I no longer work at that lab but do have the opportunity to work with
engineers that are regulary exposed to large AC magnetic fields.
I will see if any of them have had similar expriences.
Chris Wells
From: "Oscar Overton" <oover...@lexmark.com>
Chris,
I appreciate you comments and also the additional information related to
your experience.
The additional data contributes to your assessment conclusions.
Also, from your previous comment about the three options:
1. Self-testing is not comfortable but sometimes necessary.
2. Not telling others that they are being exposed would be unethical.
3. A company with a vested interest will probably not investigate but
this too borders on the unethical.
There are two additional alternatives.
1. Obtain volunteers to do testing that have been informed of the
previous results and possible risks. However, this might skew the results
because of psychological factors of knowing. The only other alternative is
inform the test subjects that they are being tested but do not reveal to
them what is being tested. This reduces the available test subjects but
reduces the chance of psychological bias. A problem with this is then the
type of people that are willing to accept conditions such as this. Is this
sample representative of the general population.
2. An independent lab does the testing. Unfortunately, unless they
get funding, no one is going to just go out and spend money on this.
Usually the only funding available for something like this is from a source
that has already taken a position and only wants proof of their position.
Therefore the source of funding often taints the perception of the results,
even if not actually tainting the testing protocol or assessment.
There are just too many variables to be able to come to a overwhelmingly
valid conclusion on just about any thing that effects humans (or for that
fact animals) in the natural environment. Many studies that seemed to
conclusively shown some trait or connection have later been shown to be the
possible result of other factors that were not addressed in the original
analysis.
I don't remember where it was that I read it (not enough time to go back
and research it now) but I read about a study that linked high power
transmission lines to cancer risk.
The authors of the original study published that they had found a
conclusive link between these two. The article showed that the data had
been groomed (probably not intentionally) to the point that the conclusion
was valid, but only for a very small geographical area. The results were
attributed to statistical grouping. There was in fact a significant
concentration of cancer events near a high power transmission line but
similar conditions in other geographies could not substantiate the
conclusions of the study. In other words, sample size matters.
Also, there were possibly other factors that were not investigated as
possible causes of the cancer concentration.
Sloppy science produces sloppy results (GIGO).
Your case provides a good data point from which to establish a study.
It may also be that you are particularity sensitive to the conditions to
which you were exposed. Similar to those with certain chemical
sensitivities.
Your experience may not be representative of the population as a whole.
Maybe you can offer your co-workers the opportunity to participate in your
study. Put the load center in their workspace (with their knowledge of
course).
Tell them it is all for the cause of science and the well being of mankind
as a whole.
Oscar
"Chris Wells"
<radioactive55man
@comcast.net> To
"Oscar Overton"
07/30/2008 09:25 <oover...@lexmark.com>
PM cc
<emc-p...@ieee.org>,
<k...@earthlink.net>
Subject
Re: RF What-if (was: RE: Another
Cancer Scare?)
Oscar - I spend a lot of time debugging systems and separating coincidence
>from cause so I appreciate your skeptic stance.
I would agree that it was not a controlled experiment but it was my
experience that I wanted to share.
My exposure was over a good part of a month and my flu like symptoms
happened at the exposure time and stopped ~ 4hrs+ later after leaving the
area.
I would estimate ~ 15 exposures events over that month and then many months
before and after without any problems.
As a result of my experience I am being cautious, limiting unnecessary
exposure and since I work with power being observant of other situations.
Chris Wells
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