cob wrote:Cindy, I think the "danger" of lasers is a little over emphasized. We use them all the time in construction and I have been "hit" hundreds of times. Has not affected my eye sight yet (things suddenly getting blurry... noe typing by feel... sorry for the mispellings... must sign off...)
No, I must disagree with you. The first time I was hit was direct. I saw a bright flash of light, followed immediately by pain. I felt as though someone had poked me in the eye and my eye was tearing apart. The pain continued for ~1/2 an hour. I ended up with some blindness in the lower left corner of that eye.
The second time was a glancing blow. Just the bright flash, and that was that. Perhaps you were lucky and only experienced the second kind of hit.
In both cases for me, the laser was being used by someone without a background in laboratory science. I guess they didn't know the protocols or cautions when using a laser.
When using a laser, it is really important to establish a protocol. We usually do the following:
1) Call out "ready to target"
2) Other person calls out ready"
3) Call out "targeting"
4) Point the laser at the ground
5) Turn on laser
6) Swing the laser up in an arc from pointing at the ground to the target
7) Hit the measurement button.
8) Call out the number
9) Repeat steps 3-8
10) Turn off laser
11) Call out "laser off"
If it is small passage, the target person turns around in the passage with their back to the laser before holding up the target. Much easier to keep the eyes out of the way.
BTW, it should be LASER not laser (it's an acronym), but I'm too lazy to retype all this.