How Carabiners Are Certified: EN 362, EN 12275 and UIAA 121

If you gaze long into a carabiner, the carabiner also gazes into you. Or maybe not.

What is certain is that a close look at a carabiner’s markings can reveal a great deal of useful information. That is exactly what we will be doing in this article: examining carabiners, the standards they must meet, and the procedures used to certify them.

Certification is a conformity-assessment procedure in which an independent organisation confirms that a product—in our case, a carabiner model—meets specified requirements.

These requirements are established by the relevant standards. The system differs from one market to another. In Russia and the EAEU, the relevant organisations include Rosstandart and the Eurasian Economic Commission. In Europe, standards are developed by the European Committee for Standardization, or CEN. In the United States, the Occupational Safety and Health Administration, or OSHA, sets workplace safety requirements, while organisations such as ASSP and NFPA develop voluntary standards.

Compliance with these requirements is assessed by an independent third party, typically a certification body working with a testing laboratory—not by the manufacturer, retailer or customer.

Once the required tests and formalities have been completed, the carabiners may be legally placed on the relevant market. Products covered by EAEU technical regulations bear the EAC mark, while personal protective equipment placed on the EU market bears the CE marking. Other markings may appear as well, but we will return to those later.

In short, carabiner certification is the process of checking whether a carabiner complies with the applicable standards, while a standard is a technical document that sets out the rules and requirements the product must meet.

Among the principal standards widely used internationally for connectors and carabiners are:

• EN 362:2004 "Personal protective equipment against falls from a height — Connectors", which covers connectors used in professional work-at-height and rescue systems.
• EN 12275:2013 "Mountaineering equipment — Connectors — Safety requirements and test methods", which covers connectors used in mountaineering, climbing and related activities.

In the designation EN 362:2004:

• EN means European Standard;
• 362 is the standard’s identifying number;
• 2004 is the year this edition was published;
• "Personal protective equipment against falls from a height — Connectors" is the title and indicates the type of equipment covered.

Standards bodies in many countries adopt European standards unchanged or with only minor modifications rather than developing separate requirements from scratch. The United Kingdom, for example, uses BS EN 362:2004, while Russia uses GOST R EN 362-2008. Both are identical to the original European standard.

This practice of aligning national standards with one another is known as harmonisation. It facilitates international trade and technical communication: users in different countries can interpret connector classes, markings and test requirements in the same way, regardless of where the product was manufactured.

However, not every internationally important connector standard follows the European system. Other examples include the American ANSI/ASSP Z359.12 and NFPA 2500. We will examine each of these standards in turn.

The work-at-height connector standard EN 362:2004 is divided into seven main sections. Read them all, and you will become a true carabiner guru:

• Scope
• Normative references
• Terms and definitions
• Requirements
• Test methods
• Marking
• Information supplied by the manufacturer

The standard is not particularly long, but it still contains enough detail to make the average reader’s head spin. We will therefore focus only on the main points needed to compare EN 362 with the other standards discussed in this article.

Let us begin with terminology. Instead of carabiner, EN 362 uses the broader term connector and divides connectors into several classes, as shown in the table below.

Each class is subject to a particular set of tests. The most important are, of course, the static strength tests. They specify the minimum loads, in kilonewtons, that connectors must withstand in different loading configurations. Manufacturers may exceed these minimum values, but they cannot fall below them.

In addition to static strength tests along the major and minor axes, all connectors are checked for sharp edges and burrs and tested for corrosion resistance. The gate opening specified by the manufacturer is also verified, along with the proper functioning of the gate and, where applicable, its resistance to loads applied to its face and side.

So, from now on, when you see a marking such as EN 362:2004/B, as on the Petzl Am’D shown below, you will know that:

• EN 362 is the identifying number of the European standard;
• 2004 is the year of this edition;
• B means basic connector, or class B.

You will, of course, also remember that a class B connector must withstand at least:

• 20 kN along the major axis with the gate closed and locked;
• 15 kN along the major axis with the gate closed but not locked;
• 7 kN along the minor axis with the gate closed.

The European standard EN 12275:2013 belongs to a family of standards developed specifically for sport climbing, recreational mountaineering, and related outdoor activities.

In its structure and general logic, EN 12275 is quite similar to EN 362. The differences lie mainly in the details. Let us begin by comparing their classifications.

Compared with EN 362, which classifies connectors mainly by their role in professional fall-protection and work-at-height systems, EN 12275 is organised around the practical needs of climbing and mountaineering. Its classes reflect how connectors are actually used in sport: for belaying, via ferrata, anchor connections, directional loading, aid climbing and pulley systems.

This is where more substantial differences appear between the work-at-height standard EN 362 and the climbing standard EN 12275.

• EN 12275 includes major-axis strength tests with the gate open for the applicable connector classes, whereas EN 362 tests connectors only with the gate closed — either locked or not locked. Under EN 12275, the open-gate test is not required for connectors with automatic gate-locking devices or for class Q quicklinks. Class K connectors are the exception and must still be tested with the gate open.

• EN 12275 covers both locking and non-locking carabiners. EN 362, by contrast, requires every connector with a gate to have either a manual or automatic gate-locking feature.

• Under EN 12275, a basic class B connector must withstand at least 20 kN along the major axis with the gate closed. If it has a manually operated locking system, the test is performed with the device unlocked. Under EN 362, a class B connector must withstand 15 kN with the gate closed but not locked and 20 kN with it closed and locked.

• Under EN 362, the specified load must be sustained for three minutes. Under EN 12275, the load is increased until the connector breaks or deforms sufficiently to release the loading pins, and the maximum force reached is recorded.

The gate-face and gate-side resistance tests use the same nominal forces under both standards — 1 kN and 1.5 kN, respectively — although some details of the procedures and acceptance criteria differ.

Unlike EN 362, EN 12275 does not include a corrosion-resistance test. It does, however, establish more specific minimum gate-opening requirements for different connector classes.

One more point concerns product markings. Unlike EN 362, EN 12275 does not require the standard number to appear on the connector itself. This gives us a useful clue: if a compliant carabiner bears the CE mark and four digits but no EN 362 designation, it is an EN 12275 climbing connector.

As you can see, EN 362 and EN 12275 differ in several important ways. Even so, connectors certified to either standard may often be suitable for the same practical tasks. This does not make the certifications formally interchangeable: the manufacturer’s instructions, compatibility with other system components, and applicable regulations still determine whether a connector may be used in a particular setup.

It is especially useful when a connector is certified to two or more standards, which is fairly common. This means that it has been assessed against a wider range of requirements and may be approved for use in more systems and environments. Multiple certifications can also give the manufacturer access to several markets. However, compliance with more standards does not automatically make a connector stronger or universally better.

Especially when we are talking about the UIAA 121 standard — which brings us to the next section.

The UIAA—short for the French Union Internationale des Associations d’Alpinisme—is the International Climbing and Mountaineering Federation and a pioneer in the development of climbing-equipment standards. In 1965, its Safety Commission issued the first standard for carabiners used in climbing and mountaineering, and EN 12275:1998 was later developed from the corresponding UIAA standard.

Today, the UIAA and CEN work together to harmonise their requirements. European climbing-equipment standards grew out of the UIAA’s earlier work, while current UIAA standards generally use the corresponding EN standards as a basis and may add further or stricter requirements.

UIAA 121 "Connectors / Karabiners" specifies requirements for connectors used in climbing and mountaineering. Products certified under the standard may carry the UIAA Safety Label — the federation’s mark of conformity.

To obtain this certification, the manufacturer must have the connector tested by a UIAA-accredited laboratory and submit the resulting test report with its application. If the product meets the requirements, the UIAA certifies it and authorises the use of the label.

So, what does UIAA 121 actually require?

• The connector must meet the requirements of EN 12275:2013, except that the EN number need not be marked on the product.
• Class K Klettersteig connectors must withstand at least 8 kN when subjected to an additional edge-loading test.

And that is essentially it — the whole standard in a nutshell :)

So, dear buyers, there is little reason to search high and low — or put shop assistants through an interrogation — for a carabiner carrying the UIAA mark specifically. The additional certification is certainly welcome, but for most connector classes it introduces no further performance requirements, so in practice you are unlikely to notice any difference from a carabiner certified only to EN 12275.

In the case of connectors, the real significance of the UIAA lies less in the limited additional requirements of its current standard than in the organisation’s historical role. The UIAA pioneered standards for climbing equipment, and its earlier work laid the foundations for the European standards that followed.

The UIAA Safety Label is voluntary and subject to fees. Manufacturers must pay an annual membership fee as well as a fee for each certified product, so some choose not to pursue it for economic reasons. For those that do, the label’s international recognition and marketing value may be just as important as the limited additional technical requirements. The absence of a UIAA mark therefore does not make an EN 12275-certified connector inferior.

Whether a product genuinely holds a UIAA Safety Label can be checked in the certified-equipment database on the organisation’s official website. This is particularly useful when assessing unfamiliar brands or markings whose authenticity is uncertain.

That concludes our look at the UIAA and European standards. In Part II, we will cross the Atlantic to examine connector standards and certification in the United States, including ANSI and NFPA.