Welding produces ultraviolet, visible, and infrared radiation intense enough to injure nearly every structure in the eye, from the clear surface layer to the retina at the back. A single unprotected glance at a welding arc can cause a painful corneal burn known as photokeratitis, while repeated exposure over a career raises the risk of cataracts and growths on the white of the eye. The damage is real, well-documented, and mostly preventable with the right gear and habits.
The Immediate Injury Everyone Calls “Arc Eye”
The most common welding-related eye problem is photokeratitis, sometimes called arc eye, welder’s flash, or flash burn. It is essentially a sunburn on the cornea caused by intense ultraviolet radiation. The cornea absorbs UV wavelengths efficiently, and when it absorbs too much, the surface cells are damaged and die off. Symptoms rarely appear right away. Most people feel fine during and immediately after the exposure, then wake up hours later with severe eye pain, tearing, light sensitivity, and the sensation that sand is trapped under their eyelids. The delay catches people off guard because they assume the exposure was harmless. UV radiation is a well-established cause of corneal disease, contributing to photokeratitis and several other conditions including pterygium and ocular surface squamous neoplasia.1PubMed Central. Damaging Effects of Ultraviolet Radiation on the Cornea
The good news is that a single episode of arc eye usually heals on its own within a day or two. The damaged corneal cells regenerate quickly. Treatment is supportive: lubricating eye drops, pain relief, and keeping the lights dim. But “usually heals” is not “always harmless.” Repeated episodes add up, and each one creates a window where the cornea is vulnerable to infection. If you have had arc eye more than once, the cumulative toll on the corneal surface matters more than any single episode.
How Welding Can Damage the Retina Permanently
Arc eye gets most of the attention because it is painful and common, but the more worrying injury is deeper inside the eye. The retina, the light-sensitive tissue at the back of the eyeball, can sustain photochemical damage from blue-light wavelengths in the welding arc. This is called welding maculopathy, and it affects the macula, the part of the retina responsible for sharp central vision. Unlike photokeratitis, retinal damage can be permanent. One published case described a patient who developed maculopathy in both eyes from a brief, unprotected exposure to an electric arc in a tight space where protective gear could not be worn.2PubMed Central. Maculopathy from an accidental exposure to welding arc The retinal changes in welding maculopathy are driven by photochemical damage from wavelengths at the blue end of the visible spectrum, not from UV or heat.3Ophthalmology Retina. Arc Welders’ Maculopathy
The distinction matters practically. A standard welding filter that blocks UV might still let enough blue light through to injure the retina if the shade number is too low for the process being used. And because retinal damage does not always cause immediate pain the way a corneal burn does, a welder might not realize anything happened until they notice a persistent blind spot or distortion in their central vision days later. There is no reliable treatment that reverses established retinal photochemical damage, which is why prevention is so critical.
Cataracts and the Lens
Between the cornea at the front and the retina at the back sits the lens, and it absorbs its own share of punishment from welding radiation. Welders and metalworkers face cataract risk from exposure to intense heat, infrared radiation, and metal fumes.4PubMed Central. Occupational Exposures and Age-related Cataract: A Review The mechanism is biologically plausible: UV radiation at wavelengths emitted during welding can cause protein changes in the lens that lead to clouding over time. However, the epidemiological picture is not as clean as you might expect. A systematic review and meta-analysis looking specifically at metal welding and cataract found that while a causal link is biologically plausible, the overall evidence from population studies remains limited and sometimes conflicting.5PubMed Central. Occupational exposure to metal welding and cataract: A systematic review and meta-analysis
What this means in practice is that welding probably does raise cataract risk over a long career, but researchers have had a hard time pinning down exactly how much, partly because so many other factors also contribute to cataracts (age, smoking, sunlight exposure, genetics). The absence of an airtight number should not be confused with absence of risk. If you weld for decades, the cumulative radiation dose to your lens is real even if the exact odds ratio is debated.
Growths on the Eye Surface
Chronic UV exposure from welding also promotes abnormal growths on the conjunctiva, the thin membrane covering the white of the eye. The two most common are pterygium, a wing-shaped fleshy growth that can creep onto the cornea and distort vision, and pinguecula, a yellowish raised patch that usually stays on the white of the eye. Both are strongly associated with UV exposure, and welders get them at elevated rates.
A study of arc welders in Western Rajasthan found conjunctival disorders in about 81% of welders compared to roughly 21% of non-welders, with pterygium present in about 28% and pinguecula in about 20% of the welding group.6PubMed Central. Prevalence and pattern of ocular disorders due to chronic exposure to arc welding among occupational welders in Western Rajasthan An earlier study found a strong relationship between pterygium incidence and years spent welding.7PubMed Central. Pterygium in welders Interestingly, a Scandinavian study found a more modest picture: pinguecula was present in 57% of welders (compared to 41% in controls) and tended to be larger with more welding exposure, but frank pterygium was rare.8PubMed. Long-term changes in the outer part of the eye in welders. Prevalence of spheroid degeneration, pinguecula, pterygium, and corneal cicatrices The difference likely reflects geography and ambient UV levels: welders in tropical or subtropical regions, who already have higher background sun exposure, seem to develop pterygium at higher rates than welders in northern climates. Either way, the dose-response pattern, meaning more years welding equals more eye surface changes, shows up consistently.
Metal Sparks and Foreign Bodies
Radiation is not the only threat. Welding and grinding throw hot metal fragments that can embed in the cornea. These corneal foreign bodies are one of the most common occupational eye injuries across metalworking trades. One study found that grinding accounted for the vast majority of corneal metallic foreign body injuries, and roughly 88% of those cases healed with a corneal scar at the injury site.9Taylor & Francis Online (Arch Environ Occup Health). Corneal metallic foreign body injuries due to suboptimal ocular protection A small scar on the peripheral cornea may not affect vision, but one over the central visual axis can cause permanent blurring. Perhaps more striking, nearly half of the injured patients in that study were wearing some form of safety eyewear at the time. This points to a common problem: safety glasses with open sides do not seal against the face, allowing particles to enter from angles the lenses do not cover. Proper welding helmets or tightly fitting goggles with side shields offer far better protection against flying debris than basic safety spectacles.
Fume-Related Eye Irritation
Even when the radiation is adequately filtered, welding fumes can irritate the eyes. Mild steel welding, one of the most common types, produces a plume of fine metallic particles and gases that contact the eye surface. A study tracking daily symptoms in mild steel welders found that they reported eye symptoms on about one in ten working days, and the risk of eye symptoms was roughly 80% higher on work days compared to days off. Working three or more years as a welder further increased the risk of eye symptoms.10PubMed Central. The ordinary work environment increases symptoms from eyes and airways in mild steel welders These symptoms, typically burning, dryness, and redness, are not as dramatic as arc eye or a metal foreign body, but they grind away at comfort and productivity over time. Good ventilation, local exhaust systems, and proper respiratory protection help reduce fume exposure at the source.
Not All Welding Processes Carry the Same Risk
The intensity of UV radiation varies substantially depending on the welding method and the materials being used. A study measuring UV output during arc welding of cast iron found that gas metal arc welding (GMAW, commonly called MIG) produced the highest effective UV irradiance, followed by shielded metal arc welding (SMAW, or stick welding), with gas tungsten arc welding (GTAW, or TIG) producing the least. Even within a single process, changing the filler material shifted UV output significantly.11Journal of Occupational Health. Comprehensive analysis of hazard of ultraviolet radiation emitted during arc welding of cast iron
This has practical implications for shade selection. The correct filter shade for TIG welding at low amperage is not the same as for MIG welding on heavy plate. Most welding safety standards publish charts matching shade numbers to specific processes and amperage ranges. A shade that is adequate for one setup may underprotect for another, even in the same shop on the same day. If you switch between processes, your eye protection needs to switch too.
Laser welding introduces an entirely separate category of hazard. Industrial lasers, particularly high-powered Class IV systems, can injure both eyes and skin through direct, scattered, or reflected beams. The optical hazards differ from arc welding because laser light is coherent and concentrated, meaning even a reflected beam bouncing off a workpiece can carry enough energy to damage the retina at considerable distance.12PubMed Central. Optical radiation hazards of laser welding processes. Part II: CO2 laser Laser welding requires its own dedicated eyewear rated for the specific laser wavelength, not standard arc-welding filters.
Auto-Darkening Helmets
Auto-darkening welding helmets have changed the safety landscape for the better. Instead of the old “nod and flip” approach, where a welder had to snap a fixed-shade helmet down before striking the arc (and sometimes skipped the step for short tack welds), auto-darkening filters detect the arc the moment it ignites and darken within milliseconds. The switching time from the light state to the dark protective state is the single most important safety parameter for these filters.13Applied Sciences. New Possibilities of Testing the Darkening of Automatic Welding Filters as Expressed by Switching Time
Quality matters here more than most welders realize. Cheaper auto-darkening helmets may have slower switching times, meaning the eyes receive a brief flash of unfiltered arc light every time the arc starts. Over hundreds of arc strikes in a day, those fractions of a second add up. Good-quality filters also incorporate failsafe designs so that if the electronics malfunction, the filter defaults to the dark state rather than staying light and leaving the welder exposed.14PubMed. Fast, automatically darkening welding filter offering an improved level of safety When shopping for a helmet, check that it meets current safety standards, and look for adjustable shade range, fast published switching time, and a failsafe-dark design. A helmet that costs two or three times as much as the cheapest option is a bargain compared to a retinal injury.
Protecting Bystanders
The welder at the torch is not the only person at risk. Anyone in the vicinity of an open welding arc, including coworkers, passers-by in a shared workshop, or helpers holding parts, can sustain the same UV injuries. Transparent welding curtains are widely used in industry to protect workers in the less immediate vicinity of welding.15PubMed. Welding screens and curtains part 2: Conformity of existing welding curtain products with ISO 25980:2023 These curtains filter UV and visible light so that people nearby can work without dedicated welding helmets, while still being able to see their own tasks.
In practice, bystander arc eye is surprisingly common. It often happens in home garages or small shops where someone else walks through the area, or in construction settings where trades overlap. If you are welding in any shared space, even outdoors, some form of barrier or warning is needed to protect people who are not watching for the flash. The intensity of UV from a welding arc can cause photokeratitis from reflected light off walls and ceilings, not just from direct line of sight to the arc.
Why So Many Welders Still Go Without Proper Protection
Given how well-established the hazards are, it is striking how many welders routinely work without adequate eye protection. A study of over 400 welders in small-scale industries found that only about 44% had good eye protection practices.16PubMed Central. Ocular protection practice and associated factors among welders in small-scale industries in Hosanna town, Southern Ethiopia, 2023 The factors associated with better protection were illuminating: higher income, greater knowledge about the risks, having a permanent (rather than casual) work pattern, and having experienced a previous eye injury. That last one is telling. Many welders do not take protection seriously until they have already been hurt. Those who had suffered an eye injury before were roughly three times more likely to use protection consistently afterward.
The barriers to protection are often practical rather than attitudinal. In small workshops, proper equipment may not be available or may be shared among multiple workers. Helmets can be hot and uncomfortable, particularly in warm climates. Short or intermittent welding tasks tempt people to skip the helmet for “just a quick tack.” And in the informal economy, where much of the world’s welding takes place, enforcement of safety standards is minimal or nonexistent. Addressing the problem requires more than telling welders to wear helmets; it requires making helmets available, comfortable, and culturally normalized.
The Contact Lens Myth
A persistent urban legend claims that wearing contact lenses while welding is extremely dangerous because the lenses can melt onto the eyeball, fuse to the cornea, or trap chemicals against the eye surface. This myth has been floating around workshops and safety manuals since the 1960s. Research into the topic found that these fears stem from unconfirmed reports and that contact lens wear in industrial settings does not pose the unique catastrophic risks the stories describe.17PubMed Central. The safety and efficacy of contact lens wear in the industrial and chemical workplace Contact lenses do not melt at temperatures a welder’s face would reasonably encounter, and they do not magnify radiation to the cornea.
That said, contact lenses are not a substitute for any other form of eye protection. They cover part of the cornea, not the whole eye, and they provide zero filtering of UV, visible, or infrared radiation. Welders who wear contacts still need a proper helmet or goggles, exactly the same as welders who do not. The real risk with contacts in a welding environment is the same as in any dusty or fumy workplace: particles can get trapped under the lens, causing irritation or abrasion. If you wear contacts and weld, keep lubricating drops on hand and make sure your helmet seals well enough to minimize debris reaching your face.
Practical Steps That Actually Matter
Knowing the hazards is useful only if it translates into what you actually do in the shop. Here is what makes the biggest difference for eye safety around welding:
- Match your shade to your process: Shade 10 might be fine for low-amperage TIG, but MIG or stick welding on heavy plate can require shade 12 or 13. If you are squinting or seeing afterimages when you stop, your shade is too low. Consult the chart published by OSHA or your country’s equivalent.
- Use a quality auto-darkening helmet: Look for fast switching time, adjustable shade range that covers your processes, and failsafe-dark design. Replace the batteries before they die and leave you unprotected.
- Wear safety glasses under the helmet: A pair of clear or lightly tinted ANSI-rated safety glasses underneath the welding helmet protects against debris when you flip the helmet up to inspect your work. Many corneal foreign body injuries happen between welds, not during them.
- Protect bystanders: Set up welding curtains or screens whenever you are working in a shared space. A verbal warning is not enough if someone glances toward the arc involuntarily.
- Control fumes at the source: Local exhaust ventilation or a fume extraction gun reduces the particle load reaching your eyes and lungs. If you are in a confined space, powered air-purifying respirators with eye coverage offer dual protection.
- Never skip protection for short welds: Some of the most serious injuries occur during “quick” jobs where the welder decides the helmet is not worth the trouble. A fraction of a second of unprotected exposure can cause photokeratitis, and the cumulative load of many brief exposures can damage the retina or lens.
When to See a Doctor
If you develop intense eye pain, watering, and light sensitivity several hours after welding or being near a welding arc, you probably have photokeratitis. Most cases resolve within 24 to 48 hours with supportive care, but you should see a doctor if the pain is severe, if you notice actual vision changes (blurriness, a dark spot in the center of your vision, distortion of straight lines), or if symptoms have not improved after two days. Central vision changes suggest possible retinal involvement, which is a different and more urgent situation than a surface corneal burn. An eye doctor can check the macula with imaging and determine whether photochemical retinal damage has occurred. If you had a metal fragment hit your eye, do not try to remove it yourself; an embedded corneal foreign body needs proper removal under magnification to minimize scarring.
For career welders, periodic eye exams are worth the time even if nothing seems wrong. Pterygium and early cataracts can develop slowly without obvious symptoms, and catching them early gives you more options. Mention your welding history to your eye doctor so they know to look for UV-related changes on the conjunctiva and lens. If you have been welding for more than a few years, consider these exams part of routine maintenance for the tools you rely on most.