---
title: Introducing the new ISO standard
url: "https://www.uvex-safety.co.uk/en/knowledge/safety-standards/safety-glasses/guide-to-en-iso-16321-12022/"
description: This guide provides the key information you need to know about the new ISO standard to ensure you can remain compliant and provide effective eye protection to keep your workplace safe.
date: 2024-07-10
modified: 2024-07-11
locale: en_GB
---

# Introducing the new ISO standard

![Simple guide to EN ISO 16321-1:2022](https://d3rbxgeqn1ye9j.cloudfront.net/images/YHYEg51T7ozJpoSYGkABszAVRAK8A6tRUXNJCICu4wg/w:375/h:210/fn:Y3NtX2d1aWRlLXRvLWVuLWlzby0xNjMyMS0xLTIwMjJfMzQ3YWUyZWM5Ng:t/cb:28fd5d4d66496b628a937c3b4d1ff761651bb363/el:1/fq:jpeg:85:avif:70:webp:80/rt:fill/aHR0cHM6Ly9kM3JieGdlcW4xeWU5ai5jbG91ZGZyb250Lm5ldC9maWxlYWRtaW4vd3d3LnV2ZXgtc2FmZXR5LmNvLnVrL01lZGlhL2tub3dsZWRnZS9ndWlkZS10by1lbi1pc28tMTYzMjEtMS0yMDIyLmpwZz8xNzIxMjA0ODA2 "Simple guide to EN ISO 16321-1:2022")

   A clear view on EN ISO 16321-1:2022
=====================================

Making the new protective eyewear standards simple
--------------------------------------------------

Since 2001, EN 166:2001 has been used for CE and UKCA certification of safety eyewear in the European Union and United Kingdom. It is now being replaced by EN ISO 16321-1:2022 – a new set of international standards that will bring some significant changes to product requirements and test methods.

  This guide provides the key information you need to know about the new ISO standard to ensure you can remain compliant and provide effective eye protection to keep your workplace safe.

       ![A simple guide to EN ISO 16321-1:2022](https://d3rbxgeqn1ye9j.cloudfront.net/images/rheLidkb3i1HdpI_nKECXkqNpfCsn07u0s-qkgTdSr8/w:250/h:171/fn:Y3NtXzI1MC1jb2F0aW5nc19mYjRlNTE3ZGE1:t/cb:e21ce1abfac347483af98b1d0596af02c8022e57/el:1/fq:jpeg:85:avif:70:webp:80/c:250:171:fp:0.5:0.65/rt:force/aHR0cHM6Ly9kM3JieGdlcW4xeWU5ai5jbG91ZGZyb250Lm5ldC9maWxlYWRtaW4vd3d3LnV2ZXgtc2FmZXR5LmNvLnVrL01lZGlhL2Nvc3QtaW4tdXNlLzI1MC1jb2F0aW5ncy5qcGc_MTY2Nzk5MTAxNw "A simple guide to EN ISO 16321-1:2022")

  Introducing the new ISO standard
----------------------------------

### When does it come into force? \*Important update\*

**EN ISO 16321** was officially published as the replacement for EN 166 in May 2023. The legal adoption date is **11th November 2025** and only products that meet its standards may be tested and certified by official bodies from this date onwards.

However, existing EN 166 certificates which are often used for CE/UKCA markings, will remain valid until their official expiry date up to a maximum of five years. This means, for example, that any products certified or recertified according to EN 166 by **11th November 2025** can be sold legally by manufacturers until **31st October 2029**. There is no end date for distributors to have sold their EN certified products by.

 ##### Early amendments to the new standard

It is common for minor adjustments or updates to be made in the initial years following the introduction of a new standard. Such changes are intended to clarify requirements, address any unforeseen issues, or refine definitions as stakeholders adapt to the revised framework. For instance, an amendment (AMENDMENT 1 2024-07) to EN ISO 16321 is currently awaiting its official publication by the European Commission. This demonstrates the ongoing process of fine-tuning the standard to ensure its effectiveness and relevance in the marketplace.

       ![EN ISO 16321-1:2022 ](https://d3rbxgeqn1ye9j.cloudfront.net/images/emaWFynDbHHWnpqrgaGaAyI4Y6li-qfJ-fe1heUh2Ck/w:345/h:148/fn:Y3NtXzcwMC1lbi1pc28tMTYzMjEtMTIwMjJfODEzOTRhMWRlYQ:t/cb:5d014d3bb78c6aabd1771e5167590b76ae7c6e98/el:1/fq:jpeg:85:avif:70:webp:80/aHR0cHM6Ly9kM3JieGdlcW4xeWU5ai5jbG91ZGZyb250Lm5ldC9maWxlYWRtaW4vd3d3LnV2ZXgtc2FmZXR5LmNvLnVrL01lZGlhL2tub3dsZWRnZS83MDAtZW4taXNvLTE2MzIxLTEyMDIyLmpwZz8xNzIwNjI3NjMy "EN ISO 16321-1:2022 ")

 ### Where will it apply?

The new ISO standard will become the official standard in many of the world’s leading PPE markets including the European Union and the UK.

  <a id="cform-17"></a>

  [    ![Download EN ISO 16321 guide](https://d3rbxgeqn1ye9j.cloudfront.net/images/Kfrgdk5x-HEuOvSBza82R2Y8EKiCcnIY6MKbKhCOVug/w:250/h:270/fn:Y3NtX2Rvd25sb2FkLWVuLWlzby0xNjMyMS1ndWlkZV82NmMyMTJiNTVk:t/cb:d9d61f4857201732e9085e862e9e7d445b72e8ca/el:1/fq:jpeg:85:avif:70:webp:80/aHR0cHM6Ly9kM3JieGdlcW4xeWU5ai5jbG91ZGZyb250Lm5ldC9maWxlYWRtaW4vd3d3LnV2ZXgtc2FmZXR5LmNvLnVrL01lZGlhL2tub3dsZWRnZS9kb3dubG9hZC1lbi1pc28tMTYzMjEtZ3VpZGUuanBnPzE3NzI2NDAxODg "Download EN ISO 16321 guide")  ](https://d3rbxgeqn1ye9j.cloudfront.net/fileadmin/www.uvex-safety.co.uk/Media/knowledge/uvex-en-iso-16321-guide.pdf?1772212250)

 Download EN ISO 16321 guide
-----------------------------

  ---

  ### Why is the standard changing?

   ##### Rationale for updating the EN standard

The EN standard for personal eye protection has been in use for over two decades. Over this period, the nature of workplace hazards has evolved, with new risks such as exposure to blue light emerging. Simultaneously, existing risks have been re-evaluated to ensure that safety measures remain relevant and effective.

 ##### Ensuring enhanced safety and durability

The publication of a new standard was necessary to achieve higher levels of safety and durability for safety eyewear, particularly in environments where hazards are diverse and challenging. This update aims to improve protection against a broader range of risks, including mechanical, chemical, and optical hazards. Furthermore, it places a greater emphasis on user comfort and wearability, recognising the importance of long-term usability for workers.

 ##### Global harmonisation and adoption

By transitioning from an EN standard to an ISO standard, the revised requirements can now be adopted internationally. This move enables global harmonisation of safety standards, fostering greater consistency in product markings across different countries. Ultimately, this process will help to establish universal minimum standards for safety eyewear, ensuring a higher level of protection for workers worldwide.

  ---

  Overview of the key changes
-----------------------------

**EN ISO 16321** comprises **EN ISO 16321-1:2022**, **EN ISO 16321-2:2021** and **EN ISO 16321-3:2022**. It introduces numerous changes from EN 166 regarding safety features and testing requirements.

It will involve new certificates and changes in labelling, markings, instructions and packaging for all safety eyewear. The ISO standard includes new safety requirements and new optional features. In some cases, the new standard demands a higher level of protection. In others, the standards become less stringent.

 **The most significant changes are outlined in greater detail below:**

| **EN Standard** | **ISO Standard** | **Summary** |
|---|---|---|
| **EN 166** Personal eye protection specifications:  **EN 170** Ultraviolet filters  **EN 171** Infrared filters  **EN 172** Solar radiation filters | **EN ISO 16321-1:2022** Eye and face protection for occupational use - Part 1: General requirements  **EN ISO 16321-1:2022** Part 6.3.1  **EN ISO 16321-1:2022** Part 6.3.2  **EN ISO 16321-1:2022** Part 6.3.3 | **EN ISO 16321** and related parts only applies to plano and prescription glasses for occupational use or use in educational establishments. It excludes face protectors intended for live-working to protect against short-circuit electric arcs, laser protectors, sports eyewear, protectors for use during medical applications, protectors for medically prescribed applications; protectors specifically intended for protection against solar radiation only or protectors intended to protect against ionizing radiation. |
| **EN 169** Filters for welding and related techniques | **EN ISO 16321-2:2021** Eye and face protection for occupational use — Part 2: Additional requirements for protectors used during welding and related techniques | The new **EN ISO 16321-2** standard is broader than **EN 169** as it applies to complete eye and face protectors used in welding and similar techniques. It includes additional considerations such as frame design and materials suitable for withstanding welding heat and sparks-compatibility with respiratory equipment. |
| **EN 1731** Mesh type eye and face protectors for industrial and non-industrial use against mechanical hazards and heat | **EN ISO 16321-3:2022** Eye and face protection for occupational use — Part 3: Additional requirements for mesh protectors | Used alongside **EN ISO 16321-3:2022**, this standard defines the requirements for mesh eye and face protectors which protect against mechanical hazards like flying particles and debris. Notably, a key difference from the older **EN 1731:2006** standard lies in the mesh design, particularly the aperture count.) |
| **EN 167** Personal eye protection - optical test methods | **EN ISO 18526-1:2020** Eye and face protection - Test methods Part 1: Geometrical optical properties | The **EN 167** standard focuses on optical testing methods for eye protection lenses whereas the **EN ISO 18526-1:2020** is a broader standard focusing on geometrical optical testing methods for a wider range of eye and face protection. |
| **EN 170** Ultraviolet filters  **EN 171** Infrared filters  **EN 172** Solar radiation filters | **EN ISO 18526-2:2020** Eye and face protection — Test methods — Part 2: Physical optical properties (Filters) | The new ISO 18526-2:2020 standard provides a single source of information for testing all types of filters. It uses more advanced testing methods and promotes consistency across different types of eye and face protection. |
| **EN 168** Personal eye protection - non-optical test methods | **EN ISO 18526-3:2020** Eye and face protection — Test methods —Part 3: Physical and mechanical properties | The new ISO standard covers more test methods for both eye and face protection building upon **EN 168** with a wider range of tests including specific hazards like splashes of molten metals, chemicals, or hot liquids. It also covers the complete eye protector and not just the lens. |
| - | **EN ISO 18526-4:2020** Eye and face protection — Test methods — Part 4: Headforms | Tests eyewear on six different head and facial sizes intended to replicate 95% of the world’s population. |

  Safety requirements
---------------------

#### Headforms

The biggest change in the new ISO standard concerns headforms. Head shapes and sizes can differ significantly from person to person. EN 166 specified only medium and small headforms, with the vast majority of testing carried out on the medium size. This approach all too frequently led to a one-size-fits-all approach to safety eyewear that compromised workers’ comfort and their equipment’s performance.

 ISO 16321 covers six different options which, following extensive international research, represents around 95% of head shapes and sizes of the world’s population. Manufacturers must carry out tests based on the fit and coverage area of the specific headform.

  If a product is certified only to size M no marking is required on the product. However, if a product **fits multiple headsizes** the marking denoting this can be found on the product and/or on the product's packaging.

|  | **Small** | **Medium** | **Large** |
|---|---|---|---|
| **European heads** | 1-S | 1-M | 1-L |
| **Asian heads** | 2-S | 2-M | 2-L |

       ![Headforms](https://d3rbxgeqn1ye9j.cloudfront.net/images/tRseWyz9Y_oIyhaitIeb-obKZTn6Nbbe5nRCBUHLXUU/w:345/h:139/fn:Y3NtX2V5ZXdlYXItc3RhbmRhcmQtaGVhZGZvcm1zXzYyZDA0ZDg1OTY:t/cb:f6c07f1091958de6cbeb33d85b2cb45e1d4f3569/el:1/fq:jpeg:85:avif:70:webp:80/aHR0cHM6Ly9kM3JieGdlcW4xeWU5ai5jbG91ZGZyb250Lm5ldC9maWxlYWRtaW4vd3d3LnV2ZXgtc2FmZXR5LmNvLnVrL01lZGlhL2tub3dsZWRnZS9leWV3ZWFyLXN0YW5kYXJkLWhlYWRmb3Jtcy5qcGc_MTcyMDY5NjY2OQ "Headforms")

 At uvex, we have always made it a priority to provide PPE that fits. We already run a highly successful eyewear fit programme that considers the employee’s facial features, work environment and personal requirements, including compatibility with other PPE. Our current range includes a broad array of options to suit different headforms and we are planning to secure multiple certifications in line with the ISO 16321 standard. This will include premium adjustable models with innovative features to ensure the ultimate close fit as well as models that are available in different sizes.

 #### Mechanical strength

Mechanical strength, otherwise known as the impact strength, is crucial in safety eyewear to protect the eyes from potential injuries caused by flying debris, projectiles or other impacts in hazardous work environments. A “bullet test” is carried out to determine the mechanical impact resistance against projectiles based on their speed, as measured in metres per second.

 In the old EN166:2001 standard there were different levels of impact resistance ranging from increased robustness in the drop ball test (level S), low energy impact resistance (level F), medium energy impact resistance applicable for goggles (level B) and high energy impact (level A) used only for face shields.

The new standards introduce three new impact levels (C, D, and E) alongside revised velocity speeds.

The ISO standard also introduces a requirement for “protection zones”, with their sizes determined by the potential speed of the projectiles in the workplace.

- Eyewear under **impact level C** (**blue**) must include an **orbital protection zone (OPZ)**.
- Eyewear under **impact level D** (**red**) must include an **extended orbital protection zone (EOZ)**.
- Eyewear under **impact level E** (**yellow**) must include a **face protection zone (FPZ)**.

      ![orbital protection zone (OPZ)](https://d3rbxgeqn1ye9j.cloudfront.net/images/DMAUeX3-PXSgWjr3BTcljy4wwrp8zK6LSBNKhizUxJo/w:345/h:384/fn:Y3NtXzgwMC1vcmJpdGFsLXByb3RlY3Rpb24tem9uZXNfMDkxNGI2OGM0Yw:t/cb:c5ee0e4bdea9ba620a3265a9f50bf34297932d74/el:1/fq:jpeg:85:avif:70:webp:80/aHR0cHM6Ly9kM3JieGdlcW4xeWU5ai5jbG91ZGZyb250Lm5ldC9maWxlYWRtaW4vd3d3LnV2ZXgtc2FmZXR5LmNvLnVrL01lZGlhL2tub3dsZWRnZS84MDAtb3JiaXRhbC1wcm90ZWN0aW9uLXpvbmVzLmpwZz8xNzgyMTI0MjM4 "orbital protection zone (OPZ)")

 These "protection zones" outline minimum areas of coverage to protect the wearer. The higher the speed of impact, the larger the protection zone coverage.

EN 166 and EN ISO 16321 are not directly equivalent. EN ISO 16321 changes both the classification model and the coverage requirements, so this table shows how the framework changes, not a one-to-one conversion.

| **Test condition** | **EN 166 marking** | **EN ISO 16321 marking** | **Minimum protection zone EN ISO 16321** | **What changes under EN ISO 16321** |
|---|---|---|---|---|
| Drop ball test | S | No marking | None specified | Basic robustness is treated differently, there is no direct one-to-one marking. |
| 45 m/s | F | C | Orbital protection zone (OPZ) | This level continues at 45 m/s, but now tied to a defined coverage requirement. |
| 80 m/s | Not previously specified | D | Extended orbital protection zone (EOZ) | A new ISO impact level, introduced with a larger required protection zone. |
| 120 m/s | B | Old standard to be phased out | Old standard to be phased out | This EN 166 classification will be phased out over the 5 years. |
| 190 m/s | A | E | Face protection zone (FPZ) | The highest impact level remains, but under ISO it is explicitly linked to full face coverage requirements. |

m/s = meters per second

 Under EN ISO 16321, mechanical testing is no longer tied to fixed product types. Protection is assessed by particle velocity and the coverage needed to prevent injury to the eyes and surrounding area.

This adjustment grants manufacturers greater flexibility for technical innovation, as they are no longer confined by the previously mandated product specifications - such as only spectacles at 45 m/s, only goggles at 120 m/s, and only faceguards at 190 m/s. With the global harmonisation of safety standards, testing criteria are now aligned across regions, ensuring consistent protection requirements, while providing opportunities for innovation in protective eyewear design. It is important to note, however, that EN 166 previously set uniquely high standards for testing, offering a level of scrutiny and safety assurance that was unparalleled.

At uvex, we have our own in-house standards known as the uvex house norms. To guarantee the high quality and integrity of our products, we exceed industry regulations with our own rigorous tests that go beyond the standard requirements. As a result, uvex will continue to test products to the higher speeds of the European impact standard EN 166:2001. It is important to note that neither EN nor ISO standards address ballistic risks; separate standards and tests, such as STANAG 4296 or MIL-PRF-32432A, apply in these cases. uvex also supplies safety eyewear that have successfully met these ballistic requirements.

 #### Lens filters

Integrated filters in the lens must fulfil a range of requirements to protect the eyes from the various dangers of optical radiation. They may also require additional features, such as the ability to accurately transmit and differentiate colours as required for specific signalling or warning systems.

**The protective features under the new ISO standard remain largely the same as under EN 166, but the markings will change.**

 #### Ultraviolet protective filters

UV filters are designed to protect the eyes from harmful UV radiation. UV radiation can come from the sun (UVB and UVA radiation) as well as from artificial light sources such as (UVC, UVB and UVA radiation).

| **UV lens filter marking according to old EN 166/EN170** | **UV lens filter marking according to new EN ISO 16321-1:2022** | **Meaning in terms of light transmittance** | **Lens shade** |  |
|---|---|---|---|---|
| 2-1.2 | U1.2 | >=74.4% of the visible light is transmitted | Mostly clear or yellow tints | **LIGHT** |
| 2-1.4 | U1.4 | Between <74.4% and >=58.1% of the visible light is transmitted | Mostly lenses with a slight tint like grey or brown for indoor and outdoor work combined |  |
| 2-1.7 | U1.7 | Between <58.1% and >=43.2% of the visible light is transmitted | Mostly lenses with a slight tint like grey or brown for indoor and outdoor work combined |  |
| 2-2 | U2 | Between <43.2% and >=29.1% of the visible light is transmitted |  |  |
| 2-2.5 | U2.5 | Between <29.1% and >=17.8% of the visible light is transmitted | Tinted "sunglass" lenses like grey or brown to protect your eyes from ‘regular’ glare |  |
| 2-3.1 | U3 | Between <17.9% and >8.5% of the visible light is transmitted | Tinted "sunglass" lenses like grey or brown to protect your eyes from extreme glare |  |
| 2-4 | U4 | Between <8.5% and >=3.2% of the visible light is transmitted |  |  |
| 2-5 | U5 | Between <3.2% and >=1.2% of the visible light is transmitted |  |  |
| 2C + filter: compliant for signalling lights (colour recognition) | UL + filter: compliant for signalling lights (colour recognition) |  |  | **DARK** |

 Signal recognition remains an optional test under the EN ISO 16321:1:2022 (as it did under EN170) however, it is depicted by the L marking - if it meets the standard, instead of the previous C. For spectacles where the frame is part of the defined protection zones, the highest filter shade level offered for the spectacle model must also be marked on the frame.

 **Sunglare filters for occupational use**
 Sun protection filters are mainly intended to protect the eye from natural glare and the sun’s natural UV radiation (UVB and UVA radiation).

| **Sunglare protection filter marking according to the old EN 166/EN 172** | **Sunglare protection filter marking according to the new EN ISO 16321-1:2022** | **Meaning in terms of light transmittance** | **Lens shade** |
|---|---|---|---|
| 5-1.1 | G0 | >=80% of the visible light is transmitted | **LIGHT** |
| 5-1.4 | G1 | Between <80% and >=43% of the visible light is transmitted |  |
| 5-1.7 |  |  |  |
| 5-2 | G2 | Between <43% and >=18% of the visible light is transmitted |  |
| 5-2.5 |  |  |  |
| 5-3.1 | G3 | Between <18% and >=8% of the visible light is transmitted |  |
| 5-4.1 | G4 | Between <8% and >=3% of the visible light is transmitted |  |
| 5 + filter: compliant for signalling lights (colour recognition) – test was already integrated | GL + filter: compliant for signalling lights (colour recognition), G4 is not compliant with L |  | **DARK** |

 Signal colour recognition was mandatory under EN 172 however, this is now an optional test under EN ISO 16321-1:2022 and depicted with the L marking. For spectacles where the frame is part of the defined protection zones, the highest filter shade level offered for the spectacle model must also be marked on the frame.

 #### Infrared protective filters

Infrared filters are designed to protect the eyes from heat radiation, such as that emitted by molten glass or metal, fire, and artificial heat emitters. The protection level increases with the average temperature of the heat source. The new ISO standard introduces the option for enhanced infrared reflection, which is marked with an additional R.

| **Infrared protection filter marking according to the old EN 166/EN 171** | **Infrared protection filter marking according to the new EN ISO 16321:1:2022** | **Lens shade** | **Heat exposure** |
|---|---|---|---|
| 4-1.2 | R1.2 | **LIGHT** | **HOT** |
| 4-1.4 | R1.4 |  |  |
| 4-1.7 | R1.7 |  |  |
| 4-2 | R2 |  |  |
| 4-2.5 | R2.5 |  |  |
| 4-3 | R3 |  |  |
| 4-4 | R4 |  |  |
| 4-5 | R5 |  |  |
| 4-6 | R6 |  |  |
| 4-7 | R7 |  |  |
| 4-8 | R8 |  |  |
| 4-9 | R9 |  |  |
| 4-10 | R10 |  |  |
|  | Amended criteria: now 1 requirement for the whole area 780-3000 nm |  |  |
| 4C + filter: compliant for signalling lights (colour recognition) | RL + filter: compliant for signalling lights (colour recognition) |  |  |
| - | RR + filter (with increased IR reflection) |  |  |
| - | RRL + filter (with colour recognition and increased IR reflection) | **DARK** | **V.HOT** |

 Signal recognition remains an optional test under the EN ISO 16321:1:2022 (as it did under EN171) however, it is depicted by an L if it meets the standard (instead of a C). For spectacles where the frame is part of the defined protection zones, the highest filter shade level offered for the spectacle model must also be marked on the frame.

 #### Welding filters

The heat and intense brightness created during welding would cause irreparable damage to the eyes without proper protection. Compliance for signalling lights was not part of the tests under the EN standard but this has been introduced under EN ISO 16321-1:2022.

Compliance for signalling lights was not part of the tests under the EN standard but has been introduced under EN ISO 16321-2:2022 as an optional test and is depicted with the L marking. This means that signal colours remain unaffected by the lens shade.

| **Welding lens filter marking according to the old EN 166/EN 169** | **Welding lens filter marking according to the new EN ISO 16321:2:2022** | **Lens shade** |
|---|---|---|
| 1.2 | W1.2 | **LIGHT** |
| 1.4 | W1.4 |  |
| 1.7 | W1.7 |  |
| 2 | W2 |  |
| 2.5 | W2.5 |  |
| 3 | W3 |  |
| 4 | W4 |  |
| 5 | W5 |  |
| 6 | W6 |  |
| 7 | W7 |  |
| 8 | W8 |  |
| 9 | W9 |  |
| 10 | W10 |  |
| Compliance for signalling lights (colour recognition) was not part of the tests | WL + filter: compliant for signalling lights (colour recognition) | **DARK** |

 For spectacles where the frame is part of the defined protection zones, the highest filter shade level offered for the spectacle model must also be marked on the frame.

  ##### Electric arc protection in safety eyewear

Electric arc protection in safety eyewear is essential for individuals working in environments where electric arcs may occur. Visors, in particular, play a crucial role in shielding workers from the hazards associated with electric arcs, which can impact not only the face but also the head. The importance of comprehensive protection is underscored by the risks posed by electric arc incidents, making it strongly recommended to use an electrician’s helmet for optimal safety.

 ##### Changes in standards

The updated EN ISO 16321-1 standard has brought significant changes to the regulation of electric arc protection in safety eyewear. Notably, the '8' marking previously used under EN 166 has been removed. Electric arc protection is no longer covered under EN 166 in conjunction with GS-ET-29. Instead, the responsibility for regulating eye protection, specifically visors intended for electric arc protection, has shifted to the IEC 62819 standard.

  ##### Testing and certification during transition

During the transition period, it is necessary for visors and helmet combinations to be tested and certified according to both ISO 16321 and IEC 62819 standards. The markings applied to these visors will accurately reflect the results of these tests and the specific protective properties they provide. This ensures that individuals receive the appropriate level of protection for their working environment.

 ##### Recommendations for optimal protection

For those seeking the highest level of safety in environments where electric arcs are a risk, the use of an electrician’s helmet is strongly advised. These helmets are specifically designed to offer comprehensive protection, acknowledging that electric arc incidents may affect both the face and the head.

  Optional features
-------------------

Further markings can be included on eye and face protection where additional safety features are included and meet the testing requirements set out in the ISO standard.

Under both the EN and EN ISO standards, **several optional features and markings remain the same**, albeit with slight modifications to some test procedures. The updates in these tests aim to harmonise standards and provide more concrete procedures for manufacturers and test laboratories. These include:

| **Marking** | **Feature** | **Description** |
|---|---|---|
| K | Resistance to surface damage by fine particles | Plastic is a very impact-resistant lens material but is also very soft and susceptible to scratches. For this reason, almost all safety spectacles are provided with an additional coating that can fulfil different tasks. In this optional test, sand trickles onto the lens and the degree of scratching is then measured in haze percentage. If the haze remains below 8%, the eye protection device qualifies for the marking. Lenses coated with uvex supravision sapphire are extremely scratch resistant on both sides whereas lenses coated with supravision excellence or supravision extreme are scratch resistant on the more dirt-prone outside of the lens and fog-free on the inside of the lens which is prone to fog-up due to sweat etc. |
| N | Resistance against fogging | Fogged-up glasses pose a safety risk. This test requires lenses to remain fog-free for a minimum of eight seconds when exposed to an atmosphere above 50°C. However, simple anti-fog coatings wash out relatively quickly and become ineffective. For this reason, the lenses are placed in water for 2 hours before the anti-fog test to simulate this premature washing out. Lenses coated with uvex supravision excellence are anti-fog for at least 16 seconds and the coating is permanent and will not wash off even after repeated cleaning. uvex supravision plus coatings provide permanent anti-fog for at least 30 seconds. With uvex supravision extreme or supravision ETC fogging is not possible as the coating does not become saturated. |
| 3 | Protection against droplets | Under EN 166, goggles were tested by spraying liquids on frontally. Visors were measured to determine whether the surface was large enough to cover the face, with no liquid testing required. However, under EN ISO 16321-1:2022, the testing method has changed, with the droplets projected onto the visor in all directions. |
| 4 | Protection against large dust particles | For extremely dusty activities, very tight-fitting safety eyewear or even full-vision goggles are required. |
| 5 | Protection against gases and fine dust particles | Goggles with this marking are often referred to as gas-tight full-vision goggles or full-vision goggles without ventilation. |
| T | Mechanical strength at extreme temperatures | Materials can behave very differently at extreme temperatures. To ensure sufficient mechanical protection at such temperatures, impact tests can also be carried out with products that have previously been preconditioned to +55°C and -5°C. While this feature was available under the EN standard, the tests now cover four impact levels: C (45m/s), D (80m/s), E (120m/s) and high mass. |

 **Some markings have seen slight changes** under the ISO standard with regard to range of eligible products. These include:

| **Marking** | **Feature** | **Description** |
|---|---|---|
| 9 | Protection against molten metals and hot solids | This test examines the non-adhesion and rapid penetration of hot, liquid metals on the lens and frame, as can occur when working in the metal industry. This marking no longer applies to goggles as molten metal presents a risk to the entire face. uvex stopped producing goggles in 2021 with the 9 marking for this exact reason. |

 EN ISO 16321-1:2022 also introduces a range of features that did not appear under EN 166. Some of the new developments are featured below:

| **Marking** | **Feature** | **Description** |
|---|---|---|
| HM | High mass impact | This means mechanical protection against larger objects is tested at a reduced speed. This is adopted from the American standard for safety spectacles. uvex already carries out high mass impact testing in accordance with the ISO requirements and will mark products accordingly. |
| CH | Chemical resistance | Unlike hand protection, there has not yet been an eyewear test procedure that confirms safe use when handling chemicals. The new ISO test involves pouring 100ml of sulphuric acid (30%), sodium hydroxide (10%), P-xylene, 1-Butanol and N-heptane over the full shield including the assembly system in 10 seconds and then leaving for five minutes. Visible deformation of the protector is not permitted, the image must not be distorted, and the assembly system must still work. Impact is also tested, as is resistance to ignition. |
| 6 | Protection against streams of liquids | This marking demonstrates that the protector prevents a high-pressure liquid stream from reaching the eyes of the wearer. Under ISO, this marking can be applied to goggles and visors. |
| 7 | Protection against radiant heat | This test is intended to determine whether the protector will protect the wearer’s face from radiant heat for a specified time. It only applies to a shield with a headband or helmet with an IR filter. The test is based on studies of typical fire conditions and any damage indicates that it may not protect the wearer’s eyes from the radiant heat. |
|  | Use in explosive atmospheres | For protectors that are intended to be used in explosive atmospheres, and if the principal ignition source is electrostatic, the eyewear is tested according to ISO 80079-36:2016, Annex D. |

 These advancements offer users more specific information about the safety eyewear required for specialised environments.

  uvex always sets the standard in safety
-----------------------------------------

We know that changes to standards can be challenging. With the introduction of EN ISO 16321, safety professionals now have to get to grips with a range of new requirements.

There’s no need for alarm. If you buy your eyewear from uvex, you’re already ahead of the game. We don’t just comply with all legally required standards; we produce products to overperform, following safety guidance as an Approved Code of Practice (ACOP) and then waiting for the legislation to catch up. We design **WEAR**ABILITY and exceptional safety into every product we produce.

Our range includes a vast array of sizes, styles and safety features that not only meet the new ISO standards but frequently go above and beyond the minimum requirements. Our team can help walk you through the process of selecting the right products for your workplace. If you’d like further guidance, please [contact one of our PPE Safety Solutions Experts](https://www.uvex-safety.co.uk/en/about-uvex/how-to-contact-us/regional-contacts/).

  ---

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