When observing welding operations, people may inadvertently glance at the intense light produced by the arc. This brief exposure can lead to significant ocular injuries. The light emitted during welding is far more complex and hazardous than typical visible light sources. Understanding its nature and effects on the eyes is important for anyone who might encounter welding activities.
The Invisible Danger
Welding arcs generate bright visible light and substantial amounts of invisible radiation, including ultraviolet (UV) and infrared (IR) light. UV and IR radiation carry energy that can harm biological tissues without immediate sensory warning. UV radiation is highly energetic and poses the primary threat to eye health during welding.
UV light can damage the outer layers of the eye because its short wavelengths are absorbed by the cornea and lens. Infrared radiation primarily contributes to heat exposure and can lead to thermal damage to the lens and retina. Both types of invisible radiation are present, making direct, unprotected viewing of a welding arc hazardous.
Immediate Reactions
Direct exposure to welding light without proper protection can lead to an acute eye condition known as photokeratitis, often called “welder’s flash” or “arc eye.” This condition is essentially a sunburn of the cornea. Symptoms usually do not appear immediately, but emerge several hours after exposure, typically between 6 to 12 hours later.
Individuals experiencing photokeratitis report severe eye pain, feeling as though sand or grit is in their eyes. Other common symptoms include intense light sensitivity, blurred vision, excessive tearing, and noticeable redness of the eyes. These symptoms can be debilitating and typically last for 24 to 48 hours, depending on the severity of the exposure.
Potential Long-Term Impacts
Repeated or prolonged exposure to the intense radiation from welding arcs can contribute to chronic eye conditions over time. One significant long-term risk is the development of cataracts, which involves the clouding of the eye’s natural lens. This condition impairs vision and can eventually require surgical intervention.
Another potential long-term effect is pterygium, a fleshy growth on the white part of the eye that can extend onto the cornea. This growth is often linked to chronic UV exposure and can cause irritation or even obstruct vision in severe cases. While less common, some research suggests a possible association between long-term UV exposure and certain forms of macular degeneration, a condition affecting the central part of the retina responsible for sharp, detailed vision.
Protecting Your Eyes
Preventing eye injuries from welding light requires appropriate protective equipment. Welding helmets equipped with specialized filter lenses are designed to block harmful UV and IR radiation. These filters are rated with specific shade numbers, ranging from 9 to 14, to ensure adequate protection. Standard sunglasses are insufficient because they do not offer the necessary level of UV/IR filtration or visible light reduction.
Safety practices, such as using welding screens or curtains, also help protect bystanders from accidental exposure. If accidental exposure occurs, seeking medical attention is important, especially if symptoms persist or worsen. Applying cold compresses to the eyes can help alleviate discomfort, and avoid rubbing the eyes, which can further irritate the cornea.