question about using green laser (class 3b) attached to a laser distance meter

[kq702]

Hello everyone, I do alot of measuring houses and I use a Bosch Laser distance meter to measure the dimentions. Quite often when the sun is out it is very hard to see the red dot however. I also purchased some red glasses which help in viewing the beam, but even with the glasses it is very hard to see in bright light. So I purchased a green laser (thought it was class 3A, but it is class 3B ). I then molded it to fit onto my laser distance meter and now when I can easily see where the red beam is located by pressing the green beam switch. As you can see in the photos below the green beam is much brighter.

My only problem is if this is dangerous at all? I obviously never would point it at someone while I press the green beam button but is there a chance that something like a reflection can also be dangerous to the eye? For example if I aim the beam onto the peek of a house and the beam hits a metal piece of trim, could the reflection off the metal cause damage to someones eyes if they are looking up at it? If so then obviously I will have to get a lower powered laser but just wondering if this type of laser would be suitable for the use I am looking for?

 

[white91formula]

I am pretty sure that OSHA has safety requirements for 3b lasers as they can burn skin dependent on intensity. We use 3b lasers at work to laser mark tissue in the body for review at a later time. I would check to see what they require and go from there.

 

[Alabama who?]

The reason that the green beam is easier to see is that your eye is 10 or more times more sensitive to green than to red. If you bought your laser from a site that gave a milliwatt rating of 5mW or less, then you don't need to worry about brief reflections. Even with very low milliwatts you should never stare into a laser beam.
There are two types of green lasers.
The older type has 3 crystals. The beam goes through several complicated stages, including one that has infra-red. Sometimes there is a filter that blocks that from the output. Sometimes there isn't. If there isn't then the beam can have more power than is safe.
The new type has a single crystal that generates green directly.
The way to tell the difference is the wavelength. If it is near 532nm, then it is the older 3-cryatal type. If it is near 515nm the it is the new single-crystal type.
The 3-crystal type tends to get out of alignment easily. I never had one that lasted a year.
The single crystal type is more expensive. I paid $20 last year for my 5mW. As an astronomy pointer it is great.