A flash burn is a painful inflammation of the cornea, which is the clear tissue that covers the front of the eye. A flash burn occurs when you are exposed to bright ultraviolet (UV) light. It can be caused by all types of UV light, but welding torches are the most common source. That’s why it is sometimes called ‘welder’s flash’ or ‘arc eye.’
Flash burns are like sunburn in the eye and can affect both your eyes. Your cornea can repair itself in one to two days, and usually heals without leaving a scar. However, if the flash burn is not treated, an infection may start. This can be serious and may lead to some loss of vision.