Welding Protection Glass: The Complete Guide to Lens Shades, Safety Standards & Eye Protection

Why Your Eyes Are the First Casualty of Every Arc

You strike an arc and the world goes blinding white for a split second. Then, hours later, comes that gritty, sand-in-the-eyes burn that tells you your eyes took a hit. That’s arc eye, and it happens faster than you can blink. The right welding protection glass is the only thing standing between your retinas and an arc that throws off radiation more intense than direct sunlight.

Welding protection glass is the catch-all term for the filter lenses, plates, and auto-darkening filters that sit between your eyes and the arc. You’ll find it in helmets, handheld shields, goggles, and face shields. Whatever the form, the job is the same: block the dangerous wavelengths while letting you see the puddle well enough to lay a clean bead.

The Three Radiations an Arc Throws at Your Face

An arc isn’t just bright. It’s a radiation source across three bands, and every one of them can hurt your eyes.

• Ultraviolet (UV): Invisible and relentless, UV radiation burns the surface of your eye the same way sun burns skin. This is the cause of arc eye, and it can do damage in seconds.
• Visible light: The blinding flash you see. Stare too long and you get the dazzling headache and temporary vision loss that comes with it.
• Infrared (IR): Invisible heat radiation that penetrates deeper, gradually damaging the lens and retina over years of exposure.

UV and IR are the sneaky ones because you can’t see them and don’t feel them building up. By the time symptoms show up, the damage is already done.

Arc Eye: The Injury That Sneaks Up on You

Arc eye has a scientific name: photokeratitis, a painful burn of the cornea caused by UV exposure. The cruel part is the delay. You feel nothing when it happens. Symptoms — stabbing pain, red and watery eyes, light sensitivity that makes you flinch at a lamp — typically appear a few hours after exposure. Welders wake up in the middle of the night feeling like someone poured sand under their eyelids. For a full breakdown of the condition and the gear that prevents it, see our guide to protective eyewear for welding.

Your Whole Crew Is at Risk, Not Just the Welder

Because arc radiation travels, OSHA requires filter lenses with an appropriate shade number not only for the welder but for observers too, including fire watch personnel. That rule lives in 29 CFR 1910.133, part of the eye and face protection standard. In practice, that means a shop where someone strikes an arc while a coworker grinds nearby is a shop with two people who need protection.

It also means the risk doesn’t stop at your eyes alone. Sparks, spatter, and slag add a mechanical threat on top of the radiation hazard, which is why good protection covers the face as well as the eyes.

What This Guide Will Help You Do

Choosing the right lens isn’t guesswork, but it’s more than grabbing the darkest glass on the shelf. Too dark and you can’t see the puddle; too light and your eyes pay the price. The right shade depends on your process, your amperage, and whether you’re running fixed or auto-darkening filters.

Over the next sections, we’ll walk through the types of lenses, translate the shade chart, compare fixed and auto-darkening gear, unpack the standards, and show you how to care for your glass so it keeps protecting you. Whether you’re practicing in a garage or running a production line, the goal is simple: protect your vision for a lifetime of welding.

What Is Welding Protection Glass? Types of Welding Lenses Explained

“Welding protection glass” is the shop-floor shorthand for whatever dark, light-filtering material sits between your eyes and the arc. The name stuck from the days when lenses were cut from actual tinted glass. Today it’s an entire product category: fixed-shade filter plates, auto-darkening filters, goggles, shields, and the cheap clear plates that keep them alive. Knowing what each piece does keeps you comfortable and protected.

One thing ties every type together. All quality filter lenses stop essentially 100% of the UV and IR radiation an arc throws off, a point OSHA’s eye protection rules make clear. The shade number only governs how much visible light gets through. That single fact clears up most of the confusion beginners have.

True Glass vs. Polycarbonate: Why “Glass” Is a Legacy Term

Real glass lenses still exist for some welding goggles and fixed-shade plates, but the modern default is polycarbonate. Polycarbonate is lighter and far more impact-resistant, which matters when a grinder throws debris or a chipping hammer sends a scale flake flying. Glass resists scratches better; polycarbonate absorbs impact better. Both appear in ANSI-rated products, so you’re really choosing based on the form factor and the helmet you already own.

The Main Types of Welding Lenses

• Fixed-shade filter plates: a single, permanent shade. Simple, rugged, and inexpensive. Ideal when you run the same process at the same amperage all day.
• Auto-darkening filter (ADF) lenses: electronic cartridges that stay light until the arc strikes, then darken in a few milliseconds. Adjustable shade and sensitivity mean one hood covers many jobs.
• Welding goggles: compact eye protection for light, low-fume work like torch brazing, soldering, or light spot welding where a full helmet is overkill.
• Face shields: clear outer shields that protect the whole face from spatter and grinding debris; they must be worn over filter lenses, never instead of them, for arc welding.
• Clear cover lenses: the inexpensive sacrificial plates that sit just outside the filter.

How Shade Numbers Work

Shade numbers run from about 2 up to 14. The higher the number, the darker the lens and the less visible light it passes, so you can stare at a 200-amp arc through shade 10, but shade 5 would leave you squinting. What surprises many new welders is that the shade has nothing to do with UV or IR protection. A shade 5 lens and a shade 13 lens block the same invisible radiation; the shade only tunes brightness for comfortable viewing. Never drop below your process’s minimum shade to “see better.” According to AWS’s shade selection guidance, comfort and safety both depend on matching shade to amperage and process.

The Role of the Sacrificial Cover Lens

The filter is the expensive part; the cover lens is the part that dies for it. Cover lenses are thin clear plates that clip in front of the filter to catch spatter, sparks, smoke, and scratches. When the view gets hazy or pitted, you swap a few-dollar plate instead of the filter. Run without one and you’ll etch the filter itself.

Choosing a Form Factor

The right format depends on the job, the fume, and how long you’re welding.

A full helmet with an ADF is the modern default for anyone doing serious work, while goggles and hand shields suit lighter tasks. For layered protection — filter lens plus safety glasses plus a face shield — see our protective eyewear guide. Setting up a shop from scratch? Our guide to welding facilities covers screens, ventilation, and PPE storage so protection stays within reach.

The Science of Arc Radiation: UV, IR, and Visible Light

An arc is not just heat and sparks. It is a compact, fiercely bright fusion reaction that throws off electromagnetic radiation across a wide spectrum. For eye protection, that spectrum breaks down into three bands: ultraviolet (UV), visible light, and infrared (IR). Each one reaches the eye differently, and each one causes a different kind of injury.

Ultraviolet: The Invisible Burn

UV sits just below visible light on the spectrum, which is exactly why it is so dangerous: you cannot see it coming. A welding arc emits UVA, UVB, and UVC in large amounts. The outer surface of the eye, the cornea, absorbs most of that UV, and the damage shows up as photokeratoconjunctivitis — arc eye. It’s a painful inflammation of the cornea that typically appears hours after exposure, which is why welders often feel “sand in the eyes” at 2 a.m. rather than at the moment of the flash. Even a brief, indirect exposure can be enough to trigger symptoms.

Here’s a detail that surprises many welders: the protection standard is wider than the eyewear standard. ANSI Z49.1:2021 requires eye protection that filters ultraviolet radiation from 380 nm up to 400 nm, extending beyond the 380 nm upper limit defined in ANSI/ISEA Z87.1. In plain terms, safety glasses that only meet the general Z87.1 benchmark may not cover the full UV range an arc actually produces.

Infrared: The Slow, Silent Heat

IR radiation arrives as radiant heat. An arc, and the flame of a torch, can heat the skin surface and the tissues immediately below it. On the eye, that heat is absorbed by the cornea and lens. IR exposure is not instantly painful, so it rarely triggers a reflex to look away, yet it is associated with cataract risk over years of cumulative exposure. That long timeline is what makes IR so sneaky — the damage builds quietly.

Visible Light: Glare and Afterimages

The visible band is the part you actually see, and it is blindingly intense — far brighter than any surface in sunlight. Staring into it causes glare, afterimages, and eye strain. You squint, your eyes water, and by the end of the day everything feels tired and gritty. A properly shaded lens knocks that visible intensity down to a comfortable, workable level while still letting you see the puddle.

Why Shielding Gas and Reflections Raise the Stakes

UV output isn’t fixed. The inert shielding gases used in MIG and TIG welding can intensify ultraviolet radiation, pushing exposure risk higher. That’s worth knowing whether you’re working with a gas-shielded setup or comparing it to gasless MIG welding with flux-cored wire. It also connects to process choices like TIG welding polarity, since AC and DC arcs behave differently at the work piece.

And UV doesn’t stop at the arc. It bounces off nearby walls, ceilings, and bright metal surfaces. A welder a few metres away, or someone facing a reflective partition, can catch a serious dose without ever looking at the arc directly. That is why curtains and screens matter as much as your hood. Bystanders and helpers are at real risk.

All of this is why lens shade numbers and standards exist. The shade number is simply a calibrated filter density matched to the radiation intensity of a given process. OSHA’s eye and face protection rules and its welding-specific requirements exist precisely because the damage is invisible until it’s done — and the standard sets filter densities that keep UV, IR, and visible exposure within safe limits. It takes the guesswork out of protecting yourself.

Shade Numbers Explained: The Complete Welding Lens Shade Chart

A shade number tells you how much light a welding lens blocks. The scale runs from about 2 (nearly clear, like sunglasses) up to 14 (so dark it’s almost opaque). It’s a logarithmic scale, so every step up roughly doubles the filtering power. A shade 10 isn’t a little darker than a shade 9 — it’s meaningfully darker. That’s why jumping two or three shades can be the difference between seeing your puddle clearly and seeing nothing at all.

The trick is that shade numbers aren’t arbitrary. OSHA sets minimum protective shades by process and amperage, while AWS and ANSI publish recommended comfort shades that often run one or two numbers darker. The legal floor keeps your retinas safe. The comfort shade keeps you from squinting all day and developing the gritty burn of arc eye. In practice, most welders split the difference, landing somewhere in between and adjusting by feel and by how their eyes respond after a long shift.

The Full Welding Lens Shade Chart

Use this table as your starting reference. “OSHA min” is the regulatory floor from 1910.252. “Comfort” reflects the AWS/ANSI recommendations most experienced welders actually use. Treat the numbers as a launch point, not gospel — your helmet’s lens quality, the ambient light in your shop, and even the tint of the lens can nudge you up or down a step.

Notice the pattern: lower amperage means a lighter shade, and higher amperage means a darker one. TIG runs hotter and slower than stick, so it climbs the shade scale faster — which is why a welder who lives in shade 10 for stick might reach for shade 12 on a heavy TIG pass. On a small-bore stainless job, controlling that arc with the right TIG polarity matters, but so does protecting yourself while you dial it in.

The OSHA Rule of Thumb

Regulators give you a range, not an exact number, because arc brightness depends on your eyes, your helmet, and your working distance. OSHA’s practical guidance is simple: start with a shade that’s too dark to see the weld zone, then step down one shade at a time until you can clearly see the arc and the puddle. If you can see the weld pool but the arc still feels harsh, stop. That’s your shade.

Over-darkening is safer for your eyes than under-darkening, but it has a cost. Too dark and you can’t track the puddle, read the arc, or judge travel speed — and bad visibility leads to poor beads. Too light and you’re gambling with UV burns and the sand-in-your-eyes sting of photokeratitis. The goal is the lightest shade that still kills the glare without costing you control.

The Combined-Shade Rule for Filtered Eyewear

Many welders wear filtered safety glasses or a face shield under a hood. When two filtering lenses stack, the shades don’t add in a simple way, but the practical rule is this: the combined effect of both lenses should equal the shade required for the operation. On the job that usually means lighter glasses under a darker helmet lens. If you’re unclear what to put underneath, our guide to protective eyewear for welding breaks down the layering.

One more habit that saves eyes: match your shade to the process before you strike an arc. Setting up a machine for gasless MIG welding or dialing in 3/16 E7018 amperage means you already know your running current — so you already know your shade. Pick it first, then pull the trigger.

Fixed Shade vs. Auto-Darkening Lenses: Which Is Right for You?

Walk into any welding supply shop and you’ll face the same fork in the road: a plain fixed-shade filter plate that costs a few dollars, or a modern auto-darkening helmet that costs ten to fifty times more. Both protect your eyes. The difference is how they do it, and that difference shapes how you actually weld.

How Auto-Darkening Filters Work

An auto-darkening filter (ADF) sandwiches liquid crystal cells between layers of glass or polycarbonate. Photo sensors watch for the sudden infrared and ultraviolet burst of an arc. When they detect it, a control circuit applies voltage to the liquid crystals, flipping them dark in a fraction of a millisecond. That’s faster than your blink reflex, which is exactly the point. You can see your joint clearly right up to the moment the arc starts, then the lens snaps dark before damaging light reaches your eye.

Most ADFs offer adjustable shade settings, commonly shade 9 through 13, plus a grind mode that leaves the lens clear or lightly tinted so you can work with a grinder without flipping the hood up. Power comes from a small battery, a solar cell, or a hybrid of both. Solar-assisted models still carry a battery for backup, since an arc alone can dim an already weak cell.

Fixed Shade: Simple, Cheap, Unbreakable

A fixed shade plate is a single tinted lens, usually glass, at one permanent shade. There’s no wiring, no sensor, no battery, and nothing to fail. You flip the helmet down before you strike, weld, then flip it back up. For decades that’s how everyone worked.

The catch is visibility. You’re blind to the joint until the moment the hood drops, which makes precise starts harder. That penalty hurts most on low-amperage work like TIG, where the arc is soft and you need to watch the puddle closely. It’s also where a variable ADF earns its money. If you’re dialing in thin material, our guide to TIG welding polarity pairs well with a good variable-shade lens.

Head-to-Head Comparison

Where Each One Shines

Low-amperage TIG is the ADF’s home turf. The current is small, the arc is quiet, and a variable shade lets you drop to 9 or 10 so you can see the puddle. High-amperage stick and heavy flux-cored work are forgiving of fixed shades because you don’t need microscopic control. If you spend your days running flux-core polarity setups on thick plate, a rugged fixed-shade hood does the job without electronics to worry about.

Reliability is the ADF’s real liability. Batteries die, sensors get blocked by spatter, and cold weather can slow the switching response. Fixed shades never have a bad Monday. Many pros keep a cheap fixed hood as a backup for exactly this reason.

A Simple Decision Framework

• Hobbyist, occasional welds: A quality ADF with a 9–13 range gives you the most flexibility for the least hassle. Pair it with solid welding practice to build muscle memory.
• Production professional: Use an ADF for precision TIG and a fixed-shade backup for reliability. Never let a dead battery leave you blind mid-arc.
• Tight budget: A fixed shade works fine if you mostly run high-amperage processes. Just match the shade to the job.

Whichever you pick, the choice matters less than using it every single time. For a broader look at layering protection, see our guide to protective eyewear for welding.

Standards and Regulations: OSHA, ANSI Z87.1, and ANSI Z49.1

Walk into any welding shop and you’ll hear three sets of initials thrown around: OSHA, ANSI, and ISEA. They sound like alphabet soup, but each one plays a distinct role in keeping your eyes safe. OSHA regulations carry the force of law, ANSI/ISEA Z87.1 sets the performance bar for the lenses themselves, and ANSI Z49.1 ties the two together for welding specifically. Here’s how to read the system.

OSHA: Where Eye Protection Becomes Law

OSHA rules are legally enforceable, and three sections matter most for welding eye protection. In general industry, 29 CFR 1910.133(a)(5) requires employers to ensure employees use filter lenses with a shade number appropriate for the work being performed, and it applies whether that lens lives in a helmet, a hand shield, or a pair of goggles. That single paragraph is why your boss can legally tell you to swap your shade 10 for a shade 12 on a high-amperage job.

The companion rule, 29 CFR 1910.252, covers welding, cutting, and brazing. It requires that welders and their helpers be protected from arc rays, sparks, and flying debris, and it’s the regulation inspectors cite when they check that everyone near the arc has something on their face. OSHA’s own fact sheet on eye protection during welding summarizes these duties in plain language.

Construction work falls under 29 CFR 1926.102, which includes Table E-1, a ready-made shade chart. For example, it calls for shade 10 when running SMAW with 1/16 to 5/32-inch electrodes, and shade 14 for carbon arc welding. Shipyards have their own version in 1915.153, with the same structure and intent. The takeaway: the shade numbers you choose aren’t arbitrary, they’re baked into federal code. When you’re planning a shop, our guide to setting up welding facilities shows how these rules translate into real-world layout.

ANSI/ISEA Z87.1-2025: The Performance Standard

OSHA tells you that you must protect your eyes. ANSI/ISEA Z87.1-2025, the current American National Standard for occupational and educational eye and face protection devices, tells you how well the protection must actually perform. It governs lens clarity, optical quality, coverage, and impact resistance. The standard is updated roughly every five years, and the 2025 edition is the one currently in force.

The marking that matters is Z87+. The plus sign means the lens and frame passed high-velocity impact testing, so they can shrug off a flying spark or a chunk of grinding wheel without shattering. A lens marked only Z87 passed basic impact tests; Z87+ is the mark you want on anything that lives near an arc.

ANSI Z49.1:2021: The Welding-Specific Standard

ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes, is the welding industry’s own safety standard. The 2021 edition requires eye and face protection to comply with ANSI/ISEA Z87.1, then goes further with Table 1, the Guide for Shade Numbers, adapted from AWS F2.2. It covers everything from gas welding and brazing to the heaviest arc processes, so whatever process you run, there’s a number with your name on it. This is the table referenced across the industry for matching shade to process and amperage.

So why does this matter at the checkout counter? Uncertified cheap lenses are a gamble with your retinas. A lens may look dark enough and still let through harmful UV and IR radiation, because darkness alone doesn’t filter radiation. Certified lenses are tested for optical quality too, so you’re not fighting distortion and eyestrain on top of everything else. Before you buy any hood or replacement lens, check for the Z87+ mark and the shade number, and check the standard that governs your work setting. For a full rundown of what to wear under and around your hood, see our guide to protective eyewear for welding. Your eyes will be doing this job long after the gear wears out, and no bargain-bin lens is worth arc eye.

How to Choose the Right Welding Protection Glass for Your Process

Walk into any welding supply shop and you’ll see a wall of lenses in every tint imaginable. The trick is matching the shade and lens type to the process you actually run. Get it right and you’ll see your puddle clearly, stay comfortable, and protect your eyes. Get it wrong and you’re either squinting through a blacked-out lens or staring into an arc that’s far too bright. The good news is that the decision comes down to a handful of variables, and once you know them, choosing a lens takes seconds.

Here’s the process-by-process breakdown.

The Quick Match: Shade by Process

Why the Process Changes Everything

TIG demands clarity. At low amperage you’re watching a tiny puddle and feeding filler wire by feel and sight. A heavy tint turns that into guesswork, so TIG welders typically run lighter shades around 8–10 and invest in the clearest optics they can afford. Understanding your setup matters here too, since polarity choice affects arc brightness and bead behavior. On thin material at 45–60 amps, dropping to an 8 can mean the difference between a clean stack of dimes and a wandering arc you can’t follow.

Stick is the opposite. SMAW throws a violent, spatter-heavy arc at high amperage. That intensity is why stick calls for the darkest shades, 12–14, especially on thicker electrodes like those covered in our E7018 amperage guide.

Oxyfuel is a whole different animal. There’s no electric arc, just a gas flame, so shades of 3–8 are plenty. Borrowing your stick helmet for the torch will leave you blind to the flame.

Look Beyond the Shade Number

Shade is the baseline, but four other factors decide whether a lens actually suits your work:

• Optical clarity. Precision TIG rewards a high optical-class lens that keeps the puddle edge sharp and color-true.
• Switching speed. Fast tack welding and rapid restarts expose you between arcs. A high switching speed (measured in milliseconds) keeps the lens dark when the arc re-strikes.
• Grind mode. Multi-task jobs benefit from a helmet with a grind setting that drops to a light tint so you can chip and grind without swapping helmets.
• Fit over glasses. If you wear prescriptions, choose a large-window or “cheater”-compatible helmet with enough depth to clear your frames without fogging or pinching, and enough height to see the whole puddle.

If you’re still building fundamentals, pair the right lens with solid technique. Our welding practice guide and wire welder beginner’s guide cover the skills side. And when your arc quality tells you something’s off, checking good and bad MIG welds helps you diagnose settings without blaming the lens.

Your Simple Decision Checklist

1. Identify the process: TIG, MIG, flux-core, stick, plasma, or oxyfuel.
2. Note your typical amperage range.
3. Pick the shade band from the chart above, erring darker as amps rise.
4. Choose lens type: fixed for single-process work, auto-darkening for mixed tasks.
5. Add grind mode if you grind and weld with one helmet.
6. Confirm it fits comfortably over your prescription glasses.
7. Verify the lens meets ANSI/ISEA Z87.1 impact and filtration requirements.

For a broader look at eye and face protection categories, see our protective eyewear guide. Match process to shade, prioritize clarity where it counts, and always keep a clear impact lens handy for grinding.

Care, Maintenance, and When to Replace Your Welding Lens

Your welding protection glass only performs as well as the condition you keep it in. A clean, undamaged lens gives you a crisp view of the puddle and the joint. A scratched, foggy, spatter-caked one does the opposite: it forces you to strain, squint, and lift your hood for a better look, which is exactly when accidents happen.

The Cover Lens: Cheap Insurance

Most helmets use a cover-lens system: a thin, inexpensive outer plate that catches spatter and grit, and sometimes an inner plate that shields the filter from smoke and sparks. Treat these as sacrificial. Replacing a worn cover plate costs a couple of dollars; the filter lens it protects can run $50 to $200 or more, and an auto-darkening unit can cost several times that. The math is simple — swap the cheap part often so you never have to buy the expensive one early.

Cleaning Without Damaging the Lens

Clean your lenses the gentle way. Mild soap and lukewarm water with a soft, lint-free cloth is all you need. Skip harsh solvents, acetone, ammonia-based glass cleaners, paper towels, and shop rags — these attack anti-fog and anti-scratch coatings and can cloud polycarbonate over time. Never dry-wipe a lens that has grit or metal dust on it; you’ll grind scratches straight into the surface. Rinse first, then wipe gently. If you’re setting up a dedicated cleaning station, the layout advice in our guide to planning safe welding facilities applies just as well to lens care.

Scratches, Pitting, and Spatter Burns

Light surface scratches and minor pitting are annoying but not always fatal. A few flecks that don’t sit in your line of sight can often be tolerated on a cover plate, but once scratches scatter your view of the arc or pits catch light and create glare, replace it. Deep scratches, embedded spatter, and burn marks in the filter are a different story: scratched, pitted, or cracked lenses reduce visibility and increase eye strain, and any damage in your field of view should be swapped out promptly. Spatter that’s fused to a filter is really a sign to upgrade your cover-lens habit.

When a Filter Lens Must Be Replaced

Cover plates are disposable, but the filter lens deserves a firm rule: replace it the moment you spot trouble. That means cracks of any size, delamination where the layers start separating or peeling at the edges, discoloration, or a haze that no amount of gentle cleaning removes. On auto-darkening filters, watch for slow or uneven darkening, flicker, ghosting at the edges, or a shade that no longer matches its setting — a degraded response means the lens isn’t blocking radiation when it should. ANSI Z49.1:2021, which sets maintenance requirements for eye and face protection, is clear that damaged protectors must be repaired or replaced rather than pressed back into service.

Storage and Battery Care for ADF Units

Where you leave your helmet matters as much as how you clean it. Store it in a clean, dry place away from direct sunlight, heat sources, and grinding sparks. UV exposure degrades plastic and LCD layers over time, and heat warps lenses and shortens battery life. Don’t toss it loose into a toolbox where it can get dropped or scuffed. For auto-darkening units, replace coin-cell or AAA batteries before they leak — a weak battery shows up as sluggish darkening, a dim shade, or flicker. If the unit sits unused for months, pull the batteries or check them before your next job.

The ritual takes seconds: inspect your lens before every session, wipe it down, and replace worn covers the moment you notice them. Clearer vision means better welds and less fatigue, and it’s a habit that pairs naturally with good protective eyewear for welding for grinding, cutting, and torch work.

Common Mistakes, Bystander Safety, and Pro Tips

Most arc eye cases and slag injuries don’t come from people who never wear protection. They come from split-second shortcuts taken under pressure. Here are the habits that do the most damage, and how to fix them.

The Mistakes That Cost People Their Sight

The worst offender is “cheating” the hood: lifting it to position the electrode or check your line, then striking the arc with the lens still up. Lifting the hood while striking the arc is a leading cause of flash burns and slag-in-eye injuries. You glance away for half a second, the arc flares, and the damage is already done. The fix is simple: flip the lens down before the electrode touches metal, every single time.

The close second is choosing a shade that’s too light for the amperage. A lens that feels “clear enough to see” on thick plate is usually unsafe. Shade numbers aren’t a style choice; OSHA’s welding standard ties them to your current. When in doubt on heavy plate, err darker. A slightly dim view beats a burnt cornea.

Bystander Safety: Protecting Everyone Within 20 Feet

Anyone within 20 feet of a welding arc should wear eye protection or be shielded by an opaque barrier. That’s not overkill. Reflected UV can burn eyes without a direct line of sight, and the arc’s output travels well beyond your position. Helpers, fire watch, and nearby workers all count. Put a screen up, not just a verbal warning.

Bystanders don’t need a dark shade, though. Clear polycarbonate safety glasses with side shields block essentially all ultraviolet light, which is why a helper can watch the work without squinting into a welding lens. What they can’t do is watch the arc with nothing on their face.

Physical barriers matter just as much. Welding screens and curtains used to protect nearby workers should meet AWS F2.3, Specification for Use and Performance of Transparent Welding Curtains and Screens. When you plan your shop’s layout, position screens so no line of sight reaches the arc. That’s a detail worth building into your welding facilities setup from day one.

Reflections and the Grinding Trap

Shiny surfaces are an underrated hazard. An arc reflected off polished stainless, aluminum, or a bright concrete wall can deliver UV to someone standing well away from the weld. Two welders facing each other can flash each other through reflected light, and even a quick tack off a reflective surface can catch a passerby. Move reflective material, hang curtains, or adjust angles so arcs point away from people.

Grinding deserves its own rule: never grind with a dark welding lens. You can’t see the contact point clearly, and a tinted filter isn’t built to stop a shattered wheel. Wear clear, impact-rated polycarbonate with side shields, and add a face shield for heavy work.

Pro-Tips Checklist

• Keep your hood down before you strike, every time, no exceptions.
• Match shade to amperage and process, and check the chart when you change settings.
• Set auto-darkening shade and sensitivity before the arc, never mid-weld.
• Wear clear polycarbonate safety glasses under your hood for grinding and chipping.
• Put a screen or curtain between your arc and everyone else.
• Tell helpers and fire watch they need filtered eye protection, not just bystander glasses.
• Check for reflective surfaces before you strike an arc.
• Inspect your lens for cracks, pitting, and loose filters before each shift.

If you or a teammate is pregnant, understand the full picture, including radiation and fume exposure, in our guide on whether you can weld while pregnant. Protection is a group effort, not a solo one.

Conclusion: Protect Your Vision for a Lifetime of Welding

If you remember nothing else from this guide, remember this: your eyes are the one piece of equipment you cannot upgrade, repair, or replace. OSHA’s welding standard treats eye protection as mandatory for good reason. A single unprotected glance at an arc can cause arc eye, and repeated UV exposure is linked to long-term damage including cataracts. Both outcomes are entirely preventable.

Arc eye is the most common welding injury for a reason. Symptoms do not show up during the weld; they arrive hours later as a gritty, burning sensation, sensitivity to light, and tearing. By then the damage is done, and the only treatment is rest and time. Prevention, by contrast, works instantly and every time.

The good news is that the solution is simple and cheap. Correct welding protection glass costs a few dollars, yet it prevents injuries that can end a career in a fraction of a second.

The Takeaways That Matter

• Shade numbers match the process and amperage. Higher shade numbers mean darker lenses and less visible light transmission, but UV and IR protection is built into every compliant filter lens regardless of shade.
• Quality lenses block 100% of UV and IR. That is the part that protects your retinas and lens over decades, not just during a single weld.
• Standards exist for a reason. OSHA 1910.133 and ANSI Z87.1 set the minimum bar, while ANSI Z49.1 adds welding-specific guidance. Compliant gear is not optional paperwork; it is your first line of defense.
• Maintenance keeps protection reliable. Scratched, cracked, or pitted lenses scatter light, hide defects, and reduce the protection you think you have.

Put the right shade number, ANSI Z87.1-compliant equipment, and proper maintenance together and you eliminate the vast majority of welding eye injuries. Miss any one of them and the risk climbs fast. Every shade change, every lens check, and every replacement part is a small habit that pays off over an entire career at the bench.

Your Final Pre-Weld Eye Checklist

1. Confirm your shade number matches the process and amperage.
2. Check lenses for cracks, pits, and scratches before every session.
3. Verify your helmet and safety glasses carry ANSI Z87.1 marks.
4. Make sure the lens fits snugly and blocks light from the sides and top.
5. Keep a spare lens on hand and replace damaged ones immediately.

Your vision is a lifetime investment, and protecting it takes seconds. Whether you are running a hobby MIG rig in the garage or managing production cells, the rule never changes: protect the eyes first. If you are building out a safe workspace, start with our guide to planning and setting up a safe welding shop, then review the full breakdown of protective eyewear for welding. Sharpen your technique safely with our welding practice guide, and if you weld around family, our guide to welding while pregnant covers the extra precautions. Weld smart, weld protected, and keep your sight for the whole journey.

Frequently Asked Questions

What shade welding glass do I need for MIG welding?

For MIG (GMAW) welding at 60–160 amps, use shade 10–12 for comfort, with shade 7 as the OSHA minimum at low current. At currents above 160 amps, move to shade 12–14. Start darker than you think you need, then step down until you can see the weld pool clearly.

What is the darkest welding lens shade?

Shade 14 is the darkest standard welding lens shade, used for heavy stick welding with large electrodes, carbon arc welding, and very high amperage processes. Shades above 14 exist for special applications like laser welding but are not used in conventional arc welding.

Do welding lenses block UV and infrared radiation?

Yes. All quality welding filter lenses block essentially 100% of harmful UV and IR radiation regardless of their shade number. The shade number only controls how much visible light passes through, so a lighter shade still protects your eyes from UV and IR.

What is arc eye and how long does it last?

Arc eye, or welder’s flash, is photokeratitis — a painful UV burn of the cornea that feels like sand in the eyes. Symptoms appear a few hours after exposure and typically heal within one to two days, but repeated exposure can cause permanent damage, so prevention with proper lenses is critical.

Can I use my welding helmet for grinding?

No — a dark welding lens makes it impossible to see your work while grinding. Use a clear impact-rated grinding shield, or an auto-darkening helmet with a grind mode that keeps the lens clear, and always pair it with safety glasses underneath.

What does ANSI Z87.1 mean on a welding helmet?

ANSI/ISEA Z87.1 is the American National Standard for eye and face protection devices. A Z87.1-compliant helmet has passed impact and optical radiation tests; the Z87+ marking adds high-velocity impact certification. OSHA requires welding eye protection to meet this standard.

Can I wear prescription glasses under a welding helmet?

Yes. Most welding helmets are designed to fit over prescription glasses, and many welders wear safety glasses or filtered goggles underneath. If you wear filtered eyewear under the helmet, the combined shade numbers of both lenses should equal the shade required for the process.

How fast do auto-darkening welding lenses switch?

Auto-darkening filters darken in a fraction of a millisecond — far faster than the human blink reflex — when their sensors detect the arc flash. This speed is why ADF helmets let welders position the electrode with a clear view and still be protected the instant the arc strikes.

Authoritative Sources & Further Reading

• https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.133
• https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.252
• https://www.osha.gov/sites/default/files/publications/OSHAFACTSHEET-EYEPROTECTION-DURING-WELDING.pdf
• https://www.govinfo.gov/content/pkg/CFR-2020-title29-vol8/pdf/CFR-2020-title29-vol8-sec1926-102.pdf
• https://pubs.aws.org/content/free_downloads/AWS-Z49-2021.pdf
• https://webstore.ansi.org/standards/isea/ANSIISEAZ872025
• https://www.aws.org/magazines-and-media/welding-digest/2025/november/wd-nov-2025–complete-welding-lens-shade-chart–safety-guide-for-eye-protection
• https://www.cdc.gov/niosh/docs/88-110/pdfs/88-110.pdf
• https://stacks.cdc.gov/view/cdc/209336/cdc_209336_DS1.pdf
• https://www.osha.gov/shms/chapter-8