In terms of occupational safety, lasers are divided into laser classes. Each class has its own laser radiation limits and precisely defined risks for working with a particular class of laser. These are classes 1, 1C , 1M, 2, 2M, 3R, 3B and 4.

In our offer you can find mainly the following classes: 1, 1M, 2, 2M, 3R, exceptionally 3B.

9) Safety at work

The lasers are sub-classified in light of labour protection. Each of classes has its own laser emission limits as well as well-defined risks when working with each concrete laser class. There are firstly following classes to be found in our offer: 1M, 2, 2M, 3R, 3B.

It is necessary to have in mind that the risks in Standard IEC 60825-1 are specified exactly for spot lasers. With dot pitch 1mm² (the diameter makes then 1,128 mm with circular beam section). In case of using optic e.g. for a line, there is perceptible decreasing output incident on surface with accruing distance. Herewith, there is also decreasing the risk of retina damage.
 
Simplified safeness example:
Class 3R is max 5mW in visible spectrum at spot-laser (with the spot-surface of 1mm²) . There is no need to use protective aids there is a natural eye-wink reflex enough for us to get protected. This reflex disallows limit violation of incident terminal energy of 0,25mJ/mm² in 0,25s on eye-retina. A simple head distract out of the laser beam is also enough.

We however need to make use of a stronger laser of 100mW, which belongs to the class 3B if it is a spot-laser, but we are going to work with a line-laser. Considering theoretically that the line is 1 mm thick we can, by means of simply division of line length and output, find out an approximate(*) effective power impinging on the surface 1mm2. Then, providing the line is 100mm long and 1mm thick, on 1mm² surface impinging value amounts approximately 1mW only  (100mm / 100mW = 1mW/mm²). For safety reasons we multiple 2x see (*). Well, the result is 2mW/mm² provided the line is 10cm long! It is ca. in distance of 5cm from the laser optical system and emissive angle 90°. We are therefore “with our hazard” deep in the class 3R, not too far from the class 2M (class 2M= max 1mW). Dangerous hazard threatens therefore at very close view only, namely at the distance of few centimetres only between laser and eye.

In spite of that I recommend in any case not to depreciate the risk. I want only to call your attention to the fact that the risk is restricted and it occurs under certain circumstances only. Much greater danger is presenting by children and intoxicated as well as impaired persons. They are even able to compete for that “who outstay it…”.

(*) – it is approximate therefore because the output is distributed unequal, according to Gausov-curva (see art. 6). Therefore on the margin of the line there is less light than in the centre. It is desirable for this reason to multiply at least two-time to obtain the brightest point and a safe reserve. 

You can find detailed specification for the single classes in the appended table.

ES declaration of conformity