So I'm a HUGE proponent of laser safety, but there's too much sensationalism involved in a lot of this new hype.. even in this article. It drives me nuts.
"Class 4" lasers cover a HUGE range of power levels, from 500mW to many kW. While it is true that diffuse reflections from MANY Class 4 lasers can cause eye injuries, lasers in the 500mW-1W range or less are not likely to cause eye damage from diffuse reflections. Reflections from glass or any other type of specular reflections are a whole different story and can cause instant, massive damage to ocular tissue even at powers FAR less than Class 4. Also, while it is true that many Class 4 lasers can start fires very quickly, at the power ranges produced by these specific 445nm diodes sparking a fire (actual open flame) in anything under a moment or two of continuous exposure on a surface is highly unlikely. Basically at these power levels (500mW-1W) a person would pretty much have to set out purposefully with the idea of starting a fire in mind, or they would have to leave the laser on and unattended for a relatively long period of time. I'd be surprised to see accidental instant combustion or anything uncontrollable.. not that it's impossible of course.
So to recap, Class 4 lasers are EXTREMELY dangerous and GREAT CARE must be taken in their usage... but I just wish a lot of these people who are writing about how these new portables are going to bring blindness and armageddon to the whole world in general would inject a little reality into their arguments instead of melodrama. I guess one could say "better safe than sorry" but it still irks me.