Lasers used for welding applications radiate inthe infrared spectra, which are not visible to the humaneye. The intensive fiber laser light radiate in the visible spectrum but invisible for humans, is especially dangerous to the eye. Fibre laser radiation penetrate through to the retina which can be destroyed irrevocably by relatively little radiation.
Misdirected laser radiation can come directly from the laser and threaten the eyes as a result of a faulty parameter setting, an opened cover, a displaced mirror etc. Other hazards include skin burn or inﬂammation from combustible materials as a result of misdirected laserradiation. The greatest hazard, however, usually stems from reﬂected laser radiation: the major share of the laser radiation is reﬂected by coldmaterial ﬁrst. To this we can add reﬂections of work piece edges, as a result of turbulence in the weld pool etc.
Misdirected radiation and reﬂections must be blocked off. That is why the law stipulates that the laser beam and the work zone must be in an enclosure. Beyond that, all those present, and the machine operators in particular, should wear protective goggles that are appropriate for the laser radiation being used. Fbre laser radiation are very dangerous to the eye and require special protective measures andapproved safety goggles.
Standard protective goggles made of glass or acrylic glass are not suitable at all,
as glass and acrylic glass allow ﬁbre laser radiation to pass through!
Easy to wear protection glasses - Comparable to comfortable sunglasses
Full protection of the eyes - Great view!
Finaly you can weld and see what you do before, during and after the welding!
The classes are as follows:
Class 1: the radiation is not dangerous and no protection equipment needed
Class 1M: the radiation is not dangerous when used without optical instruments but may become dangerous when used in combination with optical instruments - no protective equipment required if used without optical instruments
Class 2: The radiation emitted is not dangerous due to aversion responses including the blink reﬂex – no protective equipment needed
Class 2M: The radiation emitted is not dangerous due to aversion responses including the blink reﬂex but may become dangerous when used with optical instruments - no protective equipment required if used without optical instruments
Class 3R: The radiation from these lasers exceeds the maximum permissible exposure values so is dangerous to the eyes and safety glasses are recommended
Class 3B: Direct laser view is dangerous so safety glasses are mandatory ⇒ fiber laser welding
Class 4: Both direct and diffuse radiation is dangerous so personal safety equipment is necessary ⇒ certain fiber laser welders
WOBBLE-3 Series = LASER RADIATION CLASS 4
This is the highest class of laser radiation. Radiation in this class is very dangerous, and viewing of the diffuse reflection may be dangerous. Class 4 laser beams are capable of setting fire to materials onto which they are projected.
Class 4 lasers are required to have:
specific safety protocols including remote interlock
beam stop or attenuator
warning signs and labelling
elimination of specular reflections
use of eye protection where there is a potential eye hazard
use of protective clothing
requirement for medical examination immediately if there is a suspected injury
provision of appropriate training on safe use of equipment including maintenance
safe work procedures for control of hazards
Considerations for workshop and laboratory design for class 4 lasers include:
an area for storing protective eyewear
key locks to prevent unauthorised and unprotected personnel from entering
a non-defeatable door interlock
signs at entrance to lab/workshop
laser beam path must be enclosed
beams must be positively terminated
laser work area must be free of unnecessary specular surfaces
curtain materials must be fire resistant
a clearly visible power cut-off switch which kills power to the laser
a warning light must be located outside of the lab door to indicate when the laser if firing
other controls as necessary
- Never point the laser beam at anyone’s eyes!
- Do not look directly into a laser beam!
- Always wear protection glasses!
- If the laser light accidentally strikes your eyes, close your eyes and immediately move your head out of the laser beam.
- Do not use any focusing optical device to look at the laser beam while working with lasers.