dan@brand.usc.edu (Dan Antzoulatos) (10/23/87)
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. Any comments? Dan Antzoulatos [USC - Signal and Image Processing Institute] ARPANET: dan@brand.usc.edu USENET: ...!sdcrdcf!usc-oberon!brand!dan or ...!mcvax!seismo!sdcsvax!sdcrdcf!usc-oberon!brand!dan
hburford@enprt.Wichita.NCR.COM (Harry Burford) (10/27/87)
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
dave@onfcanim.UUCP (11/05/87)
The lasers used in barcode scanners are almost certainly under 1mW in beam power, which makes them class II. A class II laser is considered no more dangerous than looking at the sun, or other very bright light source (quartz-halogen lamp, carbon arc). Your natural reaction to such a bright light, if it enters your eye, is to blink, and the light intensity is such that no damage is done in the time it takes to blink. The only way to damage your eye is to deliberately look at the light source instead of blinking. In fact, a barcode scanner could use a much more powerful laser than 1mW and still be safe as long as it was scanning, since no matter where your eye is it cannot receive the beam for more than a very short period.
rees@apollo.uucp (Jim Rees) (11/10/87)
The lasers used in barcode scanners are almost certainly under 1mW in
beam power, which makes them class II.
I took a look last time I was in my local supermarket. They have the
scanners with the * shaped windows, which I think is what the original
question was about.
The scanner in question was clearly marked "class IIA." There was also
a caution about not looking directly at the beam for too long.
The cashier looked at me a little funny as I was checking this out.