If I had to rank PPE by how seriously it gets taken in the average workplace, eye protection would be near the bottom of the list.
Not because eyes aren't important. Obviously they are.
But because safety glasses are small, cheap-looking, easy to misplace, and — let's be honest — often chosen by whoever did the last office supply order rather than anyone who actually thought about the task.
So here's a deep dive into eye protection. What it actually does, why selection matters far more than people think, and what is about to change with the standard.
Eyes Are Remarkably Easy to Damage and Impossible to Replace
Around the world, hundreds of thousands of eye injuries happen in workplaces every year. A significant proportion of them are preventable with the correct eye protection.
The hazards that can affect eyes at work include:
Mechanical impact — flying particles, fragments, dust, sparks
Chemical splash — liquids, aerosols, vapours
Radiation — UV, infrared, intense visible light, lasers, welding arcs
Biological hazards — in healthcare and laboratory settings
Dust — fine particles that irritate or damage the cornea
Different hazards require fundamentally different types of protection. This is where many workplaces fall down immediately.
Spectacles vs Goggles vs Face Shields: They Are Not Interchangeable
Let's clear this up once and for all.
Safety spectacles (glasses with side shields) protect against direct and low-energy lateral impact. They are not sealed against the face. Liquids, fine dust, and vapours can still get in from the sides, top, and bottom. For splash risk: not enough.
Safety goggles fit close to the face and form a seal. Direct ventilation goggles protect against impact but allow some airflow — useful for comfort but not for chemical vapours. Indirect ventilation goggles block splash and fine particles more effectively. For chemical work or fine dust: this is your starting point.
Face shields protect the whole face but are almost always used over other eye protection, not instead of it. They are not primary eye protection on their own.
A worker who is grinding metal can use safety spectacles.
A worker handling corrosive liquids cannot.
Both are wearing "safety glasses." Only one is actually protected.
The Lens Matters More Than the Frame
Most people choose safety eyewear by frame. Is it comfortable? Does it look okay? Does it fit over prescription glasses?
All valid questions. But the lens is where the actual protection lives.
Optical class determines visual quality. Class 1 lenses offer the clearest, most accurate vision — essential for precision work, driving, or anyone who needs sharp sight. Class 2 lenses have slightly more distortion and should not be used for tasks requiring fine visual acuity or driving.
Lens coatings affect real-world performance significantly:
Anti-scratch (K) coating extends product life
Anti-fog (N) coating is not a luxury — fogged lenses get removed
UV protection varies and matters more than people realise (more on this in a future article)
Tinted lenses exist for solar glare, infrared and UV filtering, each with specific transmission ratings for specific conditions. A lens tinted for outdoor use will reduce visibility dangerously in a dark environment.
Mismatching lens to task is not a minor issue. It directly affects both protection and the likelihood that the product gets worn at all.
The Standard Is Changing — And You Need to Know About It
For over 20 years, the benchmark for occupational eye protection in Europe was EN 166:2001. Same standard. No updates. Since 2001.
That changed on 11 November 2025.
From that date, EN 166 no longer provides presumption of conformity for new certifications. The new standard — EN ISO 16321-1:2022 — takes over.
Here is what that actually means in plain language:
What changes for manufacturers and certification:
New products must be tested and certified to EN ISO 16321-1 from November 2025
Products already certified under EN 166 before that date can remain on the market until their certificate expires (maximum five years from issue date, so some will be valid until 2029)
Both standard markings will coexist in the market for several years during transition
What actually changed in the standard itself:
Bigger, heavier impact test projectile. The basic impact test now uses a heavier steel ball (~66g vs ~43g previously). Products have to be more resilient to blunt impacts.
Tighter light transmission requirements. Standard clear lenses must now allow at least 80% light transmission (previously around 74%). Better vision clarity is now the minimum.
New protection zones. The standard introduces clearer categories for how much of the face and orbital area is actually covered at different protection levels.
More rigorous thermal testing. Eyewear must now withstand heat for 120 minutes without deforming, up from 60 minutes previously.
Gap limits. Openings in frames cannot exceed 1.5mm, tested with a rigid rod — preventing particles from sneaking through gaps in the frame structure.
Better headform diversity. Six headform sizes are now used in testing, covering around 95% of the world's population. Previously only two sizes were used. (IS PPE BECOMING MORE INCLUSIVE?)
New field of view test method. The previous method was fairly subjective. The new Stoll Apertometer (fancy ;-)) approach measures from far more reference points and produces more reliable results.
What does this mean for workplaces right now?
If you are currently procuring safety eyewear:
Check whether products you are ordering are certified to EN 166 or EN ISO 16321-1
EN 166 products already in stock and in use remain compliant until their certificates expire
New purchases from compliant suppliers will increasingly carry EN ISO 16321-1 marking
When requesting quotes, ask suppliers which standard the product is certified to
This is not a reason to panic or throw out your current stock. It is a reason to be informed and to start paying attention to the transition.
The Fit Problem (Again)
New standard or old, the fundamental challenge with eye protection (and PPE in general) remains the same: fit.
Safety glasses that sit too far from the face leave a gap where particles can enter. Glasses that press on the nose or temples get pushed down, loosened, or removed. Glasses that fog up because they seal poorly or are too close to the face get taken off within minutes.
The new EN ISO 16321 standard's expanded headform range is a step in the right direction. But a product tested on six headforms still needs to be trialled on actual people in actual workplaces before it becomes the standard issue for everyone.
Involve workers in selection. Trial products before committing. And ask the people doing the work whether what they've been given actually stays on their face.
Final Thought
Eye protection is probably the most underestimated category in PPE.
It is inexpensive, simple-looking, and easy to dismiss as a box-ticking exercise.
But eyes are irreplaceable. Damage is often permanent. And most eye injuries at work happen to people who were wearing the wrong type of protection, or protection that didn't fit, or protection they'd already taken off.
Grab the right ones. Check the lens. Check the fit. And when the standard changes this November — notice.
