Weling helmets are headgear used when performing certain types of welding to protect the eyes , face and neck from flash burn, ultraviolet light, sparks and heat. Most commonly used with arc welding processes such as shielded metal arc welding and gas metal arc welding, welding helmets are necessary to prevent arc eye, a painful condition where the cornea is inflamed. Welding helmets can also prevent retina burns, which can lead to a loss of vision.