🚀 go-pugleaf

In article <4814@oberon.USC.EDU> dan@brand.usc.edu (Dan Antzoulatos) writes:
>In recent months, I have noticed the installation of new bar-code scanners
>in supermarkets, bookstores, etc, that have made me concerned as to their
>safety. The particular model in question is made by Spectra-Physics and has
>an asterisc-like (*) opening which seems to allow direct viewing of the laser 
>beams from various angles. I'm assuming the power and wavelength are within a 
>goverment specified safety range,but I still get anxious when I unintentionally
>get directly "hit" by the beams while paying and passing-by.
>
>Dan Antzoulatos  	[USC - Signal and Image Processing Institute]

I'm involved with Laser Printers and as such need to know a little about
the agency approvals necessary to operate them.   I was interested in the
Supermarket lasers too.   I can't remember what class they are, I think
they are Class II (maybe IIA or IIB or something like that).   What that
means is that they are safe to view for short periods of time.  Something
like less than 15 min. or so.  Prolonged viewing is not considered safe
exposure.  I felt real uncomfortable at the check out line when I looked
down into the beam, past the glass to read the label.   I expected to 
see something like....."If you read this, Its too lat     I'm not sure
who set the exposure standards.   Laser Printers are Class I which means
that there is no danger.    The laser is low power and is contained inside
the machine.  

Harry.Burford@Wichita.NCR.COMM