On Wed, 29 Dec 2004 08:17:53 -0800, Winston
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Just a question about this. How then can a spider or spider web set it
off? This apparently is a common cause of false alarms....

Any infrared sensor relies on a sharp contrast in heat level between
'person there' and 'person not there'. You get that from exposed skin,
not by sensing tiny temperature differences on the surface of an
insulated jacket.

--Winston