Which climbing carabiner strength do you need? Climbers often face the dilemma of choosing the right climbing gear so they can have safe climbing experience.
Carabiners differ in shape, gate type, size, weight, and strength.
- 1 Carabiner Shapes
- 2 Carabiner Gate Classification
- 3 Size and Weight
- 4 Carabiner Strength
- 5 Carabiner Strength (kN) Ratings
- 6 What Causes Carabiners to Break
- 7 Conclusion
How about we start with the fundamental carabiner shapes before we dig into their strength ratings? Carabiner shape has an effect on major axis strength and other strength positions, weight distribution, open-gate size, and ease of handling.
Numerous climbers want to utilize D-shape carabiners for its capacity to carry the weight of its load away from its gate. This limits the pressure in the middle and distributes the weight more evenly.
When To Use:
Works great for various kinds of climbing
Modified D-Shape (Asymmetric)
A modified-D carabiner, commonly known as “asymmetric carabiner,” generally functions as a regular D-shape except that it’s somewhat larger on one side and smaller on the other to reduce load capacity. Modified-D carabiners are likewise well known among the climbing network.
When To Use:
Good for carabiner break rappeling and making Bachmann knots
Pear-shaped carabiners are desired for their large gate opening. This ensures that it’s easy for you to secure your climbing gear and rope.
These carabiners are sometimes called “HMS carabiners.”
When To Use:
Primarily intended for belaying and rappelling
Also functions as anchor points for top-roping and multi-pitch climbing
Carabiners are originally molded like an oval. These oval-shaped carabiners are favored for their multifunctionality.
When To Use:
You can perform rappelling in the absence of a belay device by learning the carabiner rappelling break method with the use of your oval-shaped carabiner. Any shape can be used for this method but the oval shape is best.
Watch how to set up and improvised rappel:
Carabiner Gate Classification
A carabiner can be classified according to its gate type. Gates are broadly categorized into locking gates and non-locking gates.
Let’s discuss the different types of carabiner gates. You ready?
Screw lock carabiners involve screws that are manually adjusted for opening or securing the gate. A short metal sleeve acts as the gate screw.
Screw lock carabiners are usually D-shaped.
Auto-lock carabiners are either double-action or triple-action.
You need two steps to unlock the gates of double-action carabiners, a.k.a. twist-lock. Unscrew the metal sleeve first then slide it away from the gate opening. The carabiner will naturally secure itself once the lock is released.
Meanwhile, there are three steps engaged with opening a triple-action gate carabiner.
First, you pull the metal sleeve towards you and away from the gate opening. Secondly, you twist it. And finally, you bend the gate inwards. The carabiner will also lock automatically on its own once released.
Non-Locking (Snap) Gates
Solid gates have a bad reputation for their weight and their faulty design which is attributed to an issue called “gate flutter.”
This usually happens during a big fall where the rope inflicts heavy weight on the carabiner while it passes through. Vibration in the carabiner causes its gate to open/close a bit as if it’s “fluttering.”
Solid gates contain an inner spring within, making them more susceptible to breakage. More people prefer wire gate carabiners because of these defects.
Carabiners usually have straight gates. These gates are simple, yet functional. Straight gates are foolproof and resistant to the risks accustomed to bent gates.
Bent gates are typically solid gates too. These gates are good for one thing: hassle-free hooking of your climbing gear. But the danger in using bent gates can outweigh its benefit.
Bent gates can easily be unclipped or unlocked by accident. They are prone to getting twisted, so be careful! Clip them well on the rope side.
A wire gate is designed in such a way that it prevents gate fluttering especially when the carabiner is loaded to its maximum capacity.
The gate is built with less mass and thus less likely to vibrate. There are no loose parts that are susceptible to getting stuck, frozen, displaced, or even broken.
Most wire gates are also straight gates. They are not built with springs, but they are fashioned in a manner that ensures the springing of the gate.
Size and Weight
Large carabiners are useful for belaying and rappeling where lots of ropes are needed. A large carabiner offers a lot of room to accommodate these ropes and other climbing gear.
Small carabiners can be handy but they’re more difficult to clip and they have less room for carrying things.
Investigate the gate open clearance of a carabiner when choosing which one to buy.
Gate open clearance is measured in millimeters. It’s how wide you can open the carabiner gate. Try out the carabiner to see if the clearance fits your hand.
Climbers would generally want to carry the least weight with them whenever they ascend. This means having to choose lightweight equipment, right?
BUT light carabiners are not always a good choice.
Lighter and smaller carabiners can be very inefficient and difficult to use for different purposes. These carabiners usually break easily. They are too narrow and often have weaker gate-open strength. Watch out for these narrow carabiners as they may cause your rope to wear too soon with frequent use.
Check whether your newly bought carabiner is CE or UIAA certified to ensure its safety.
You can see these letters imprinted, engraved, or forged on the spines of trusted carabiners.
There are three positions in which carabiners are rated relative to strength.
Major Axis Strength
The major axis stretches from the top end of the carabiner to the bottom. This is the toughest positioning and the way carabiners are designed to be loaded.
Gate-open strength refers to the force that an open gate carabiner is capable of withstanding.
Carabiner gates have the tendency to open slightly during the climb or during unfortunate falls that cause “gate flutter.” Defective springs can also leave your gates unlatched or loose.
Minor Axis Strength
The spine and the gate of carabiners run through its minor axis. Weight should not be carried in this position, although there are instances wherein the carabiners get twisted and out of place.
Cross loading occurs when the minor axis is loaded. It’s the most common culprit for carabiner-related accidents. Beware!
In this position, wire gates are basically stronger than solid ones. Wires are more pliable and able to absorb more force than the stiff solid gates.
Carabiner Strength (kN) Ratings
Carabiner strength is measured by kN which stands for kilonewton or a thousand Newtons. Newton is a measurement of force as we all remember from our physics class. And 1kN is roughly about 225 lbs. This helps us to gauge how much load a carabiner can take before it breaks apart.
That’s good all good to know. But here’s the truth. Strength rating comes last when choosing the right carabiner. It’s more important to pay attention to which carabiner shape, gate type, size, and weight is suitable for the type of climbing that you want to do.
Go for the carabiner that is stronger and well adapted to your type of climbing.
UIAA tests are performed to test the force capacity of each carabiner type. The minimum UIAA carabiner strengths are listed in the table below:
TYPE OF CARABINER
STRENGTH RATING (kN)
Regular & Modified-D-Shapes
All other shapes
What Causes Carabiners to Break
As much as possible, avoid situations that may result in having broken carabiners.
Your carabiner may break due to one of the following reasons:
The nose gets trapped in some gear and then loaded. Noses usually get hooked on bolt hangers. The nose is the weakest area of the carabiner but nose strength, unfortunately, has no rating. Do keep in mind to never load the carabiner in this position.
The carabiner spins out of position or orientation and becomes cross-loaded. This is very dangerous for climbers because the force is applied to the minor axis of the carabiner instead of the major axis.
To summarize, the factors that affect carabiner strength are the following: shape, gate type, size, and weight.
The strength rating is not that important when choosing the right carabiner. It’s more essential to select which carabiner shape, gate type, size, and weight is suitable for the type of climbing that you want to do.
The best carabiner for you is the one that’s well adapted to your type of climbing.
Carabiner strength does not make a substantial difference to your climb. Carabiners with higher ratings will be stronger, but the performance of your carabiner depends on proper selection, use, and care. The breaking point of your carabiner ultimately depends on how you use it.
What do you think? Did we help you decide which carabiner strength is right for you? We want to hear from you!