Guide to Lens Markings
Select the LENS Markings below to find out more information
Lens Filter Type (protection)
| 2, 2C | UV (2C doesn’t affect colour recognition) |
| 4 | IR filter |
| 5 or 6 | Solar filter |
| 1.7 to 7 | Welding filter if no shade number |
Scale Number (shade)
| 1.2 | Clear or Amber |
| 1.4 | Blue or I/O Waterproof |
| 1.7 | Minimises or I/O |
| 2.5 | Grey or Revo |
| 3.1 | Dark Grey or Mirror |
Identity of the Manufacturer
Optical Class
1 - High Optical Quality
Mechanical Strength
| S | Increased strength |
| F | Low energy impact, resists a 6mm, 0.86g ball at 45m/s |
| B | Medium energy impact, resists a 6mm, 0.86g ball at 120m/s |
| A | High energy impact, resists a 6mm, 0.86g ball at 190m/s |
If protection against high-speed particles at extreme temperatures is required then the selected safety eyewear product should be marked with the letter T immediately after the 'Mechanical Strength' letter; eg: FT, BT or AT.
If the 'Mechanical Strength' letter is not followed by the letter T, the safety eyewear product shall only be used against high speed particles at an ambient temperature.
If the frame and lens display different certification marks (F, B or A), the lowest level should be assigned to the entire safety eyewear product.
Optional Requirements
| 8 | Short circuit electric arc |
| 9 | Molten metal splash |
| K | Resistance to scratches by fine particles |
| N | Resistance to fogging |
Certification Mark