A guide to BS EN ISO 16321-1:2022+A1:2025

BS EN ISO 16321-1:2022+A1:2025 is the current standard covering general requirements for occupational eye and face protection.

It introduces requirements for how protective eyewear is designed, tested, and marked, and replaces EN 166:2001 for new certifications.

But what if you're still using EN 166-certified eyewear? The change doesn't automatically mean your existing protection is out of date or needs replacing.

Here's what you need to know about the standard and what it means for your organisation.

What Does BS EN ISO 16321-1:2022+A1:2025 Mean for Your Business?

Let’s answer the question most people want to know straight away:

Do you need to replace existing EN-166 certified eye protection? No, not just because the standard has changed.

If your eyewear is still suitable for the job and in good condition, your team can continue using it.

You should look at replacing existing eye protection if it's:

• Damaged or showing signs of wear
• No longer suitable for the hazards involved
• Doesn't give the wearer the right fit or protection

Your risk assessment and the manufacturer's guidance should always help determine when PPE needs replacing.

What’s been introduced by EN ISO 16321-1:2022?

1. MORE HEADFORMS FOR DIVERSE TESTING

People have different head shapes and sizes, and PPE needs to account for this.

The updated standard introduces six headform sizes, compared to two under EN 166. This allows eyewear to be tested across a wider range of fit profiles.

The headform used for testing is also included in the product information, giving users clearer information when considering fit.

2. UPDATED FIELD-OF-VIEW TESTING

Peripheral vision is essential in environments where hazards can approach from any direction.

EN ISO 16321 includes updated field-of-view requirements to assess the wearer's vision while wearing the product.

There are also specific field-of-view requirements for eye protection that's intended to be worn while driving.

3. CLEARER VISION

Clear vision is an important part of effective eye protection.

Lenses without deliberate filter action must provide more than 80% luminous transmittance. For certain face shields and multiple-glazed protectors, the minimum requirement is 75%.

The standard also updated how scattered light is assessed, helping to check the quality of vision through the protector.

4. MORE FLEXIBLE HEADBANDS AND HARNESS DESIGNS

Under EN 166, headbands had to meet a minimum width requirement of 10mm.

The updated standard replaces this with a practical fit assessment for eye protection with headbands or harnesses.

This checks how securely the protection fits during movement while giving manufacturers more flexibility with product design.

5. STRONGER IMPACT REQUIREMENTS

Under EN ISO 16321-1:2022+A1:2025, all eye protectors must meet a basic level of impact protection.

The test differs from the increased robustness test used under EN 166. Additional classifications apply to products designed for higher-impact risks.

6. IMPROVED LONG-TERM THERMAL RESISTANCE TESTING

The updated standard builds on the thermal resistance requirements outlined in EN 166.

Eye protectors are tested against deformation during 120minutes of high-temperature exposure. This doubles the test duration used under EN 166.

7. NEW PENETRATION TESTING

This is a new requirement in the EN ISO 16321-1:2022+A1:2025 update.

Eye protection with ventilation or gaps between components is tested to ensure openings are no larger than 1.5mm. This helps assess the risk of particles entering through openings in the protector.

Optional requirements for eye and face protection

Alongside the main requirements, EN ISO 16321 includes optional test methods for products designed for particular environments and hazards.

These include protection against:

• Chemicals
• Radiant heat
• High-mass impact
• Explosive temperatures

Other optional features cover areas including resistance to fogging and surface damage, as well as protection against dust, liquids, and gases.

These requirements only apply where the additional protection is relevant to the product and its intended use.

Get compliant eye and face protection from SMI

Choosing the right eye and face protection for your team isn't simply about checking which standard appears on the product.

The protection needs to suit the wearer, task, environment, and hazards involved.

Whether you need:

• Safety glasses
• Safety goggles
• Face protection

We can help you find suitable options for your workplace and the risks your teams face.

Get in touch!

FAQs

What is the EN 166 standard?

EN 166:2001 was the long-standing European standard for personal eye protection.

It has now been replaced by the EN ISO 16321 series for new certifications within its scope.

What is the eye protection standard in the UK?

BS EN ISO 16321-1:2022+A1:2025 sets out the general requirements for occupational eye and face protection.

Separate parts of EN ISO 16321 cover specialist applications, including welding and related techniques and mesh protectors.