Updated on 26/08/2024
Flying particles, chemical splashes, or harmful radiation can cause permanent damage to your eyes. To ensure employee safety, you must therefore provide the right eye and face protection.
The range of safety glasses and face protectors on the market is large, with various models, designs and tints. But what makes one set of glasses or one facial shield safer than another?
A combination of wearing comfort, optimal visibility, maximum protection, and advanced design is the key to the right safety glasses or face protection for your activities.
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To start the hunt for the appropriate safety glasses or the right face shield, ask yourself the following question:
Why do employees need eye or face protection?
In other words, which risks relate to the daily activities of your employees?
Risks
The choice of safety glasses or face shields depends on the specific risks and applications:
Mechanical hazards
If there is contact with solid particles, dust and splinters, we talk of a mechanical risk. If dust or splinters end up in your eyes, they can damage your cornea or blur the lens. In this case, safety glasses often suffice.
Chemical hazards
Do you work with hazardous substances such as solvents and sprays? The small drips or splashes that are released can lead to serious infections. Conjunctivitis, an inflammation of the eye's conjunctiva, is a common occupational disease. In this situation, face shields are better than safety glasses because they protect the whole face from chemical splashes.
Thermal hazards
Molten metal, flames or hot liquids are a source of thermal risks that could damage the cornea. Face shields often offer the best protection here, as they protect the full face.
View all heat-resistant face shields
Electric hazards
A short circuit or poor electrical contact can cause an explosion. In case of a flame arc, specific arc-flash face shields offer the necessary protection. These shields often have a darker tint to protect the eyes against the intense light and UV radiation that is released by a flame arc, and fulfil standards such as the German GS-ET-29.
These flame arc face shields are integrated into a safety helmet or you can mount them yourself.
Harmful radiation: UV, laser or infrared
One of the most common risks at work are injuries due to harmful rays such as ultraviolet (UV), laser or infrared rays. If you are regularly exposed to UV rays, your retina and cornea may become damaged. Choosing a good protective lens is crucial, whether this is a set of safety glasses or a face shield.
Every workplace is different, so start with a thorough risk analysis. Once you have noted all the risks, you can decide which standards your face shields must fulfil.
Standards
In Europe, all eye and face protection devices (such as safety glasses and face shields) are CE-approved. All glasses or shields must fulfil specific requirements and tests, as set out in the valid European EN standards.
A number of tests are mandatory, others apply to wide-vision goggles but not to safety glasses and others are entirely optional. The results of optional tests can be seen in the markings on your glasses or the frames.
Below is an overview of the most important standards for safety glasses, wide-vision goggles and face shields:
| EN ISO 16321-1 NEW STANDARD |
Eye and face protection for professional use Part 1: general requirements |
|
EN 166:2001 |
Basic requirements for all types of eye and face protection, except for laser, nuclear, x-ray, and low-temperature IR radiation. |
|
EN 167:2001 |
Optical test methods |
|
EN 168:2001 |
Non-optical test methods |
|
EN 169:2002 |
Filters for welding and associated techniques |
|
EN 170:2002 |
Ultraviolet filters (UV-filters) |
|
EN 171:2002 |
Infrared filters (IR-filters) |
|
EN 172:1995/A2:2001 |
Sunlight filters for industrial use |
|
EN 175:1997 |
Equipment for eye and face protection during welding and associated processes |
|
EN 207:2010/C1:2012 |
Filters and eye protection against laser radiation |
|
EN 208:2010 |
Eye protection for adjustment work to lasers and laser systems |
|
EN 379:2003/A1:2009 |
Automatic welding filters |
|
EN 1731:2006 |
Eye and face protection with woven metal wire for protecting against mechanical hazards and/or heat. |
Most safety glasses or face shields are certified according to EN 166, sometimes in combination with a specific standard for filters. When a manufacturer produces a new pair of safety glasses, goggles or face shield, this will be certified according to the new standard EN ISO 16321:1.
Marking
All eye and/or face protectors must contain a mark indicating their performance and field of application. The field of application indicates the specific risks and circumstances for which the protection device is suitable, such as protection against certain types of radiation or mechanical impact. This marking must be displayed on the frame/holder and on the lens/shield. If the frame and lenses cannot be separated, e.g. a face shield with an integrated headband), the marking only needs to be shown on the frame. The standard number itself does not need to be displayed on the lenses, only the figures for the tested and conforming features.
See the specific markings for safety glasses and face shields here.
Marking on the lens
| Description | Symbol |
|---|---|
| Filters | |
| UV radiation | 2-X, 2C-X, 3-X |
| Infrared radiation | 4-X |
| Sunlight | 5-X of 6-X |
| Welding | 1,2 tot 16 |
| Manufacturer’s logo | Logo |
| Optical class | |
| Suitable for long-term wear for working with high visual requirements | 1 |
| Suitable for occasional wear for working with average visual requirements | 2 |
| Suitable for brief wear for working with low visual requirements | 3 |
| Mechanical resistance | |
| Minimum robustness | No symbol |
| Increased robustness | S |
| Low energy impact (45 m/s) | F |
| Average energy impact (120 m/s) | B |
| High energy impact (190 m/s) | A |
| Impact in combination with high temperature | FT, BT, AT |
| Specific area of application | |
| Electrical short arc (arc flash) | 8 |
| Molten metal | 9 |
| Optional treatments | |
| Anti-scratch coating | K |
| Anti-fog coating | N |
| Increased reflection | R |
| Original lens | O |
| Replacement lens | ▽ |
| CE marking | CE 0120 |
Marking on the frame
| Description | Symbol |
|---|---|
| Manufacturer’s logo | Logo |
| Standard | EN 166 |
| Specific area of application | |
| Liquids: droplets and splashes | 3 |
| Coarse dust:> 5 microns | 4 |
| Gas & fine dust > 5 microns | 5 |
| Electrical arc | 8 |
| Molten metal | 9 |
| Mechanical resistance | |
| Increased robustness | S |
| Low energy impact (45 m/s) | F |
| Average energy impact (120 m/s) | B |
| High energy impact (190 m/s) | A |
| Frames or shield holders suitable for a combination of an impact and high temperatures | T |
| Small head indicator | H |
| Optical radiation: In the case of optical radiation protection, this is the highest filter number lens that may be fitted. | X-Y |
| CE marking | CE 0120 |
Lens material
The lens material is the deciding factor when making your choice, as not all materials are suitable for each risk.
The table below shows which materials are most suitable for your application.
| Material/ Property |
Scratch resistant | Chemical resistant | Heat resistant | Spattering | Hot particles | Weight |
|---|---|---|---|---|---|---|
| Polycarbonate | Poor | Reasonable | Good | Very good | Reasonable | Light |
| Acetate | Poor | Good | Reasonable | Good | Reasonable | Light |
| CR39 | Reasonable | Good | Good | Reasonable | Good | Light |
| PNX | Reasonable | Good | Good | Very good | Good | Very light |
| Glass | Good | Very good | Very good | Reasonable | Poor | Heavy |
Lens tints
The tint of your safety glasses or shield affects the capacity to see colours and contrasts. A well-selected lens tint optimises perception, reduces eye fatigue, and ensures maximum clarity. It does this by controlling and balancing VLT (Visible Light Transmission). A badly balanced VLT creates under or over exposure and can lead to pain or discomfort.
Most manufacturers make the same safety frames in multiple tints so that the same model can be used for different applications.
Here are a few common tints:
Clear lenses
Clear lenses are most common and are primarily suitable for interior and mechanical applications. They transmit light well and can absorb up to 99.9% of UV light.
See all safety glasses with clear lenses
Sunshades
Mainly suitable for outdoor work, working in direct sunlight. Safety glasses with sunshades must still comply with the EN 172 standard.
Visible Light Transmission (VLT) = 10-25%
See all safety glasses with sunshades
Photochromic lenses
Photochromic lenses are suitable for sunny and less bright conditions. The lenses go darker in UV light and then lighten when the exposure reduces. These glasses are ideal for employees who frequently move between brighter and darker areas.
Visible Light Transmission (VLT) =+/ -50%
Welding lenses
Welding or grinding work requires specific welding tints. The light that is released during welding is so intense that it can cause severe damage. Those who weld using the naked eye can later experience actinic conjunctivitis, a well-known occupational disease suffered by welders.
Polarised lenses
When the light is extremely bright and reflects off water or a road, it is often hard to avoid. Particularly when driving a vehicle. Polarised lenses protect against these reflections but maintain colour recognition.
Visible Light Transmission (VLT) = 10-20%
Coatings
To extend the lifespan of glasses, manufacturers apply an anti-fogging and anti-scratch coating to the glasses:
- Anti-scratch coating: protects against scratches from dust or other flying particles
- Anti-fog coating: prevents the lens from fogging up in damp areas or after the glasses have been worn for a long time
These coatings are indicated on the glasses with the letters K (anti-scratch) and N (anti-fog).
Various brands have different names for these coatings. A few common coatings are:
- Uvex Supravision Extreme (used in models such as Uvex Sportstyle and Uvex Pheos glasses)
- Bollé PLATINUM (used in Rush, Rush+, Contour, Tryon,…)
- 3M Scotchguard
Additional comfort features
As well as protection, safety glasses must also offer the necessary comfort. Here are a few comfort-enhancing properties:
- Adjustable temples: for a better fit. You can easily adjust your frame to your face shape with adjustable temples. This can be both in height or length.
- Flexible nose bridge: The better safety glasses often have a flexible, soft rubber nose bridge with a non-slip coating. This helps your glasses stay on your face more securely.
- Frame material: A frame can be made of plastic or metal. Nowadays, plastic tends to be used more frequently. It is lighter and more flexible, so it is more comfortable to wear. Metal frames are slightly stronger but are also a little heavier.
Accessories
The big difference between basic and premium safety glasses lies not only in the materials used and comfort features. Take a look at the accessories that can be supplied too.
- Glasses cord: prevents your glasses or the shield falling to the ground
- Foam reinforcement: for extra protection against dust and particles
- Storage box with cloth: keeps the glasses or the shield clean and well protected
- Cleaning spray: for easy cleaning of the lens or shield
What you must remember
With this information, you are sure to make the right choice.
- Always start with your risk analysis and observe all the risks.
- On the basis of the risks, choose the standards that your glasses or face shield should fulfil. You will find the indicators on the products themselves.
- The lens material largely determines the protection level: polycarbonate is good for impact resistance and acetate is good for chemical resistance.
- Choose the lens tint that is most suitable for your working environment: factory hall, outdoor work, darker environment...
- Glasses and shields with coatings (anti-scratch or anti-fog) last longer and offer extra protection.
- Don’t cut corners on comfort, as these details really make a difference when you have to wear the glasses all day.
- Invest in the necessary accessories to protect and maintain your glasses.