Safe materials

[caribis2]

I think what you want is the last paragraph of this post by dan:

Materials that aren't certified laser safe

I just moved this to its own topic so it wouldn’t get lost. There’s a lot here, but the short version is that we spent a long time trying to create good advice that would allow a nontechnical person to safely use materials from unknown suppliers. We concluded that we couldn’t. The only advice we could give that would result in safe (nevermind reliable) operation would be frustratingly complex at best and misleadingly dangerous at worst (because there are supplier problems that are undetectabl…