EN 166:2001 - Personal eye protection - Specifications 

This standard specifies the functional requirements for various types of personal eye protectors, incorporates general considerations concerning designation, classification, universal requirements for eye protection, testing and application, and safety marking, and describes how both frames and lenses are to be tested.

EN 166 is the core technical standard that all PPE used to protect the eyes or face must be approved in accordance with. Depending on equipment’s intended use, protection requirements may differ.

Marking on lens/oculars must include:
• The scale number for filtering lenses/radiation protection:
2 - UV Protection (EN 170): “2” indicates that the filter may affect colour recognition.
2C or 3 - UV Protection (EN 170): “2C” (previously “3”) indicates that the filter allows good colour recognition.
4 – Infrared (IR) Protection (EN 171): protection from heat.
5 - Solar Protection (EN 172): 100% UV sun glare protection with no IR protection.
6 - Solar Protection (EN 172): 100% UV sun glare protection with IR protection.
• The manufacturer's name (note: logo or brand recommended by the manufacturer).
• Optical class symbols, ranked according to effectiveness:
Class 1 – Continuous work: suitable for occasional wear (refractive power of ± 0.06 dioptres).
Class 2 – Intermittent work: suitable for occasional wear (refractive power of ± 0.12 dioptres).
Class 3 – Occasional work: suitable for exceptional wear (refractive power of ± 0.25 dioptres).
• Field(s) of use symbols:
3 - Liquids droplets (goggles) or liquid splashes (face shields, but not those made of mesh)
4 - Large dust particles (i.e., particles size >5μm)
5 - Gases and fine dust particles (e.g., particle size <5μm)
8 - Protection against short circuit/electric arc
9 - Molten metal and hot solids
• Optional requirements:
K - Hard coat: resistance to surface damage by fine particles (optional); anti-scratch protection
N - Non-mist: resistance to misting/fogging (optional)
R - Enhanced reflectance (optional)
G - Radiant heat: mesh-type protection only
H - Eye protector designed to fit small-sized heads/faces
• Mechanical strength symbols:
None - without mechanical strength (i.e., filters only)
S - Extra strong: resists a 22 mm, 43 g ball falling 1.30 m at 5.1 m/s (oculars only)
F - Low energy impact: resists a 6 mm, 0.86 g ball falling 1.30 m at 45 m/s (any type)
B - Medium energy impact: resists a 6 mm, 0.86 g ball falling 1.30 m at 120 m/s (goggles and face shields only)
A - High-energy impact: resists a 6 mm, 0.86 g ball falling 1.30 m at 190 m/s (face shields only)
T - The letter T: indicates protection against high-speed particles heated to extreme temperatures if written following a mechanical strength symbol (e.g., F, B or A).
• Certification mark (CE)
Note: a combination of the symbols and numbers mentioned above is possible.

Marking on the frame must include:
• The manufacturer's name (logo or brand recommended by the manufacturer)
• Number of the EN Standard
• Field(s) of use symbols:
3 - Liquids droplets (goggles) or liquid splashes (face shields, but not those made of mesh)
4 - Large dust particles (i.e., particles size >5μm)
5 - Gases and fine dust particles (e.g., particle size <5μm)
8 - Protection against short circuit/electric Arc (face shields only)
9 - Molten metal and hot solids (note: goggles and face shields only)
• Optional requirements:
K - Hard coat: resistance to surface damage by fine particles (optional); anti-scratch protection
N - Non-mist: resistance to misting/fogging (optional)
R - Enhanced reflectance (optional)
G - Radiant heat: mesh-type protection only
H - Eye protector designed to fit small-sized heads/faces
• Mechanical strength symbols:
None - without mechanical strength (i.e., filters only)
S - Extra strong: resists a 22 mm, 43 g ball falling 1.30 m at 5.1 m/s (oculars only)
F - Low energy impact: resists a 6 mm, 0.86 g ball falling 1.30 m at 45 m/s (any type)
B - Medium energy impact: resists a 6 mm, 0.86 g ball falling 1.30 m at 120 m/s (goggles and face shields only)
A - High-energy impact: resists a 6 mm, 0.86 g ball falling 1.30 m at 190 m/s (face shields only)
T - The letter T: indicates protection against high-speed particles heated to extreme temperatures if written following a mechanical strength symbol (e.g., F, B or A).
• Certification mark (CE)
Note: a combination of the symbols and numbers mentioned above is possible. 

Scale Number - for lenses with filtering effect only.
The scale number is a code number and a shade number separated by a hyphen (note: welding filters have no code number). Higher shade numbers indicate a stronger filtering effect (e.g. they are darker for welding). Example: an IR filter with shade number 4 has the scale number 4-4.

 

Welding filters (See EN 169 and EN 379) No code number; shade number between 1.2 and 16; suffix denotes filter for use in gas welding with flux
UV filters (See EN 170) 2C- or 3- - code number denoting UV filter without or with good colour recognition, respectively; shade number between 1.2 and 5
IR filters (Infra-red) (See EN 171) 4- - code number for IR filters; shade number between 1.2 and 10
Sun glare (See EN 172 and EN 1836) 5- code number for sun glare filters without IR specification; shade number between 1.1 and 4.1
Sun glare (See EN 172 and EN 1836) 6- - code number for sun glare filters with IR specification; shade number between 1.1 and 4.1

 

Shade number Typical lens colour VLT range
1.2 Clear 100% - 74.4%
1.7 In/Out, yellow, clear mirrored, UVR 58.1% - 43.2%
2.5 Brown, smoke 29.1% - 17.8%
3.1 G15, smoke mirrored 17.8% - 8.0%
3,4,5,...11 Welding -