Any form of arc welding produces dangerous UV rays that can cause severe skin burns and eye damage. Every welder has at least once in his career felt the discomfort of flash burn to the eyes caused from exposure to welding flash. For several days after a flash burn the eyes feel as though they were filled with sand. It is a very uncomfortable feeling and once experienced will cause the welder to take precautions against any further incidents. Many new welders have probably found themselves, while learning the trade, lifting their welding shield to strike an arc because of course they can not see through the darkened glass plate of the helmet till the arc is started. They quickly learn that this is a very bad practice.
Early welding shields consisted of a helmet that covered the face and wrapped around the head to provide protection against not only welding arc flash but also any sparks that may be thrown about. These helmets had a viewing plate approximately two inches by 4 inches which provided a very narrow field of view. The lens plates were available in various shades of darkness because some welding procedures produce brighter flash. This situation meant that the welder working on various thicknesses of metal might have to stop and change the lens from time to time to adjust for the brightness of the flash. In addition until the welder is experienced it can be difficult to start an arc in the proper place because of the dark lens plate.
In addition to the above mentioned problems these early shields were heavy and hot. Welding itself can be hot, smokey and uncomfortable in general and the welding shield did not do much to ease these discomforts. However as usual in any situation new technology has traveled very far and produced modern new shields that fix these problems. First they are made of much lighter material. The viewing plates now are 4 inches by 5 inches or even larger. The lenses are now auto darkening. These lenses stay clear until an arc is struck and then in speeds of 1/10,000 of a second automatically darken. this allows the welder full vision while wearing the helmet.
No longer is it necessary to change lenses to get a darker shade.These modern helmets have a built in lense adjustment allowing the welder to easily adjust the lense to the shade needed. In what can only be called a magical solution all the lense adjustments are controlled by a solar battery which is
recharged by the light from the welding flash. Some helmets are available with cooling fans. What could be next? Built in stereo speakers?
As expected these new helmets are not inexpensive. However a well made helmet should last for the length of the welders working life. It is easy to research the various models available with a little time spent on the internet.
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