spyproofing your house/work building

[Darren Reed]

> 
> Don Melvin <anagld!access.digex.net!storm> writes:
> 
> > > Have I forgotten anything?
> > > 
> > Guard physical access so a mic/camera (1/8") can't be placed after
> > construction.
> > 
> > Drapes so the lip readers can't see you.
> 
> Make sure the drapes block IR.  There are instances of even local
> police forces flooding the front of a house with IR light, and
> viewing the activities inside with IR viewers -- all of this
> through closed drapes.

What sort of materials DO block IR ?  Lycra ?  Wool ?  Cotton ?

And how do we test drapes without buying them first ?