Laser Welding Helmets FAQs
Plain answers on how laser welding helmets differ from arc helmets, what the laser markings mean and how to use them safely.
How is a laser welding helmet different from an ordinary welding helmet?
An ordinary welding filter is designed for the ultraviolet, visible and infrared light of an arc. A laser welding helmet adds a filter tested for laser radiation, typically marked to the European laser eye protection standard, which blocks the wavelength your laser produces.
Some designs use a laser filter alone, and others combine it with an auto-darkening filter for arc welding as well. The marking on the filter tells you which wavelengths and laser modes it covers. Always check that the helmet matches your laser before use, and follow the manual.
What do the letters D, I, R, M and LB on the filter mean?
These markings show which laser modes and power levels the filter was tested for. The letters give the operating mode: D for continuous wave, I for long pulses, R for short (giant) pulses and M for very short, mode-locked pulses. LB is followed by a number showing the protection level, and each step up is ten times higher.
A typical marking lists a wavelength range, then the modes and levels, such as D LB7 for continuous wave. A pulsed laser needs a rating for the pulse mode as well as for continuous wave. The numbers must be compared with your laser's power, beam size and pulse details, so check them against the laser's data.
What is the difference between laser protection ratings for full protection and alignment?
The European standard for full laser protection covers eyewear tested against direct hits, so it is the rating to look for when working with a welding laser. A separate alignment standard covers visible beams only. It reduces the beam to a level that lets a technician see the spot while adjusting, and it does not cover infrared or ultraviolet beams.
Most welding lasers work in the invisible infrared, so alignment-only eyewear is not suitable for welding. Check the marking on the helmet filter shows full protection for your laser's wavelength.
Will the helmet protect me from the laser beam itself?
No. Never expose yourself to the beam on the strength of a helmet. Laser filters are tested only to withstand a direct hit for a short time, and a high optical density does not by itself guarantee that the material will survive a strong beam. Eyewear that has taken a suspected direct hit should be taken out of service even if it looks undamaged.
Safety relies mainly on the laser system itself, such as enclosures, interlocks, safe beam paths and trained operators. The helmet is the last line of defence against stray and reflected light.