EN 166 is a European standard that specifies the requirements for personal eye protection. It covers a wide range of aspects, including optical properties, mechanical strength, and protection against various hazards. Here’s a detailed introduction to EN 166:
Introduction to EN 166
Purpose
EN 166 sets the general requirements for all types of personal eye protection, ensuring they provide adequate protection against various hazards in occupational, domestic, and leisure activities.
Scope
This standard applies to all eye protection devices, including safety glasses, goggles, and face shields. It covers aspects such as optical clarity, resistance to impact, and protection against specific dangers like chemicals, dust, and radiation.
Key Requirements
- Optical Requirements
- Optical Class: Lenses are classified into three optical classes based on their optical power and light transmission. Class 1 is suitable for continuous use, Class 2 for intermittent use, and Class 3 for occasional use.
- Spherical, Astigmatic, and Prismatic Refractive Powers: These parameters ensure that the lenses do not distort vision and meet strict criteria for optical quality.
- Mechanical Strength
- Impact Resistance: Lenses and frames must withstand different levels of impact, ranging from low-energy impacts to high-speed particles. This is categorized as:
- S: Increased robustness (minimal protection)
- F: Low energy impact (45 m/s)
- B: Medium energy impact (120 m/s)
- A: High energy impact (190 m/s)
- Resistance to Aging: Materials used must resist aging and retain their protective properties over time.
- Impact Resistance: Lenses and frames must withstand different levels of impact, ranging from low-energy impacts to high-speed particles. This is categorized as:
- Protection Against Hazards
- UV Protection: Lenses must filter harmful UV radiation, and specific markings indicate the level of UV protection.
- Infrared Radiation Protection: For environments where exposure to infrared radiation is a concern, lenses must provide adequate protection.
- Glare Protection: Lenses may include filters to reduce glare and improve visibility in bright conditions.
- Chemical Resistance: Eye protectors must be resistant to chemicals and provide a seal to prevent liquid ingress in certain environments.
- Dust and Gas Protection: Goggles and face shields must prevent dust and gas from reaching the eyes.
- Additional Requirements
- Resistance to Ignition: Materials should not ignite easily or sustain combustion.
- Field of Vision: The design must ensure a wide field of vision to maintain safety and awareness.
- Comfort and Fit: Eye protection devices should fit comfortably and securely, with adjustable features where necessary.
Classification and Markings
EN 166 uses alphanumeric codes to indicate protection levels:
| Code | Protection Type | Example Applications |
|---|---|---|
| S | Increased strength (high impact) | Construction, metalworking |
| F | Low-energy impact | Laboratory work |
| B | Medium-energy impact | Woodworking, grinding |
| A | High-energy impact | Welding, explosive environments |
| N | Anti-fogging | Humid or temperature-variable environments |
Comparison with Other Standards
| Standard | Region | Key Differences |
|---|---|---|
| ANSI Z87.1 | U.S. | Stricter coverage dimensions (e.g., 40 mm × 33 mm lens size) |
| AS/NZS 1337 | Australia | Includes UV/solar filters for outdoor use |
| JIS T8147 | Japan | Focuses on high-velocity projectile resistance |
Practical Applications
- Industrial: Welding helmets (EN 175), chemical goggles (EN 170)
- Healthcare: Face shields for infection control (tested under EN 166 for COVID-19 adaptations)
- Emergency Response: Compatibility with other PPE (e.g., respirators) is critical
Challenges and Innovations
Smart PPE: Emerging AR-integrated eyewear for industrial use must still comply with EN 166
Compatibility Issues: Combining eyewear with helmets or ear protection may reduce effectiveness
Testing and Certification
Eye protection devices must undergo rigorous testing to comply with EN 166. This includes optical tests for clarity and refractive properties, mechanical tests for impact resistance, and specific tests for chemical and radiation protection. Certified products receive markings that indicate their compliance with the standard.
