| Markings Chart | BS EN166 |
| Frame | Lens |
|
| Optical Class: |
| Refractive Tolerance + 0.06 dio |
| 1 |
| Refractive Tolerance + 0.12 dio |
| 2 |
| Refractive Tolerance + 0.12/-0.25 dio |
| 3 |
|
| Mechanical Strength: |
| Minimum Robustness- |
|
|
| Increased Robustness (General Purpose) |
|
|
| Low-Energy impact (Grade 2 – 125 ft/s) |
| S |
| Medium-Energy impact (Grade 1 – 360 ft/s) | F | F |
| High-Energy Impact (570 ft/s) | B A | B A |
|
| Field of Use: |
| Basic |
|
|
| Liquids (chemical) | 3 |
|
| Large Dust Particles (Dust) | 4 |
|
| Gas and Fine Dust Particles (Gas) | 5 |
|
| Short circuit Electric Arc | 8 |
|
| Molten Metals and Hot Solids | 9 | 9 |
|
| Optional Requirements: |
| Resistance to Misting - |
| N |
Resistance to Surface Damage (Anti Scratch) |
| K |