Subject:  (High) infrared detectors (fwd)
Date:     Fri, 5 Feb 1999 035604 -0600 (CST)
From:     "Roy L. Beavers" <rbeavers@llion.org>
To:       emfguru <rbeavers@llion.org>
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---------- Forwarded message ----------
Date: Fri, 5 Feb 1999 10:52:58 +0100
From: "High, Ingrid" 
To: "'Roy L. Beavers'" 
Subject: infrared detectors

Dear All,
I have a query which I hope somebody will be kind enough to help me
with. In my office they have now installed a new light-control system.
In each area/small office there is a little plastic box (4x4
inches/10X10 cm ca, and ca 4 cm deep) with a lead attached, installed
high up on the wall (2-2,2m). It has two bowformed small "windows"
(non-clear plastic/glass) on the front. According to description it is
aimed to detect movement in the immediate area and  will then switch the
light on (the main ceiling strip-light). They say that it operates in
the infrared frequency, it is not a passive receptor, but it is sending
out an IR-field which causes a reaction when disturbed?? (don't you need
reflectors/stronger fields for that?).

Anybody knowing if this is cause for concern? What is it? Any
experience? - since I have the roof-light (strip-) disabled can I with
good conscience just put some paper over the windows? - I presume it is
a similar thing to the "burglar" lights some people have over their
entrance areas, outside - but I don't like the idea of sitting in this
all day without knowing something about it. - Just for added information
I now have 3 normal 60watt lightbulbs to light my office - does this
light contain the same frequency (whatever it is)? - and would then the
field from the detector "disappear" in the main radiation in an office
like mine?

with warm greetings to all,
Ingrid High






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Reprinted with permission of Roy Beavers, http://www.feb.se/EMF-L/EMF-L.html