This article was written with collaboration from AMGA Certified Rock Guide Max Lurie. Connect with Max on Instagram, @alpinetothemax and his website.

A common question for climbing anchors: should I use locking carabiners on the bolts/gear?

It's an important topic, and there are some strongly held opinions on this, so let's have a closer look.

Short version:

• For multi pitch climbing, using snapgate carabiners on the bolts or gear is acceptable.

• For top rope climbing, it's a generally accepted standard in the guiding and teaching world to use locking carabiners on the anchor and master point.

• We all get to choose an acceptable level of risk. Try to understand the realistic, and not imagined, risks of your methods.

Before we get into the details, let’s look at some bigger-picture concepts:

• If you have a single life-critical connection, then a locking carabiner is good practice. (For example, the rope and your belay device, and your rope or tether connection to the anchor.)

• If your anchor is “unattended”, like for a toprope, then locking carabiners can be more important.

• If your anchor is “attended”, like a multipitch climb with someone next to it the whole time, with hands and/or eyes on the anchor, locking carabiners are generally not required.

• It's helpful to understand the difference between perceived risk reduction and actual risk reduction.

• The argument of, “I want to reduce my risk as much as possible, so I use lockers everywhere on my anchor”, is a bit simplistic. How far do you take that? Do you use lockers on the first couple of quickdraws when you’re sport leading? Steel carabiners are much stronger than aluminum ones, so do you use steel carabiners? I'm guessing the answer to both of these is no for just about everybody.

• It's good to have a solid understanding of the capabilities and limitations of your gear, and let those guide your decision rather than emotion, hearsay, and “that's-the-way-I-learned-it”.

• Be aware of generally accepted best practices among guides and industry professionals. Also be aware that what might be standard practice in one industry, such as using triple action lockers for say tree/arborist work, does not necessarily mean it's also good practice to use that same gear for recreational climbing.

Here are some thoughts from AMGA Certified Rock Guide Max Lurie:

“We perceive a locking carabiner to be “safer” in the context of connecting an anchor leg to a bolt / cam / stopper / whatever. Can you articulate what specifically makes a locker safer? How do carabiners commonly fail, are lockers and non-lockers really that different in those scenarios? I am trying to get folks to think critically and articulate what exactly they think they are achieving with a locker vs. a non-locker.

From a physics perspective… non lockers can come unclipped if backclipped, that isn’t a concern here so we can dismiss it. Strength along the major and minor axis is pretty similar between lockers and non-lockers. So we can dismiss that as well. Being loaded over an edge and potentially snapped is a serious concern for any carabiner, but lockers tend to be a little beefier so they may be more resilient, but this is just a guess. I don’t have any data to back that statement up. The gate rubbing against the rock and opening could be a concern. With properly orienting the spine of a non locker against the rock it becomes equivalent to a locker. In conclusion, I don’t think a locking carabiner is physically any more resilient than an non-locker (with the context of our discussion).

Us, the human factor is where I think the locker makes more sense than the non-locker. All of the above makes one very strong assumption, and that is that we’ve done everything “right” with our anchor setup. There are too many times to count that I have stumbled upon a top rope anchor that was worse than dog shit. One leg of the anchor is attached to a dead poorly rooted shrub, with just a non-locker on the other side. Two strands of material but they are completely unequalized. Unfortunately endless examples exist.

The fact is that we are our own worst enemies, and we use lockers because we are Neanderthals who cannot be trusted with our own lives.”

The snapgate crowd says:

• Totally fine to use them on the anchors.

• The failure of any single non-locker would not cause catastrophe.

• What's the realistic mechanism of failure for a snapgate carabiner? Any mechanism that could cause them to both fail at one time is so incredibly unlikely that using them is acceptable; each carabiner is connected to a separate independent strand of the anchor.

• On a multi pitch anchor that is “attended”, any potential problem can be hopefully noticed and fixed right away.

• Think of it this way: if you were building a trad anchor with, say, 3 cams, most people would be fine with using the snapgate racking carabiners on the cams. (If you wanted lockers everywhere, and built a three piece anchor, you probably have to carry about six extra lockers, which is a little ridiculous.) So, if you’re cool with using snapgates on your cams when building a gear anchor, logic says you should also be comfortable with them when building a bolt anchor.

• On a related note, it makes no difference whatsoever which direction the carabiners face when clipped to the anchor points. They can both face right, face left, face each other or face opposite, it makes no difference. The concept of “opposite and opposed” carabiners applies at a masterpoint, not when clipped onto the the bolts.

The locker crowd says:

• It’s a system that you rely on 100%. Even if the chance of failure is very tiny, why not use lockers and make it pretty much zero?

• Modern locking carabiners are so lightweight and inexpensive that there's no reason not to use them. With the carabiners I'm using in the photo, the difference is about 10 grams in weight and $3 in cost more for each locker. You won’t notice either.

• Having lockers everywhere gives some people a warm fuzzy feeling of confidence, which can be important.

• You need to carry a few spare carabiners for your anchor, so why not make them locking?

What about lockers on the bolts for a top rope anchor?

For a top rope, using lockers on the bolts is something many people prefer. This is what I’d call an “unattended” anchor, because you build it, you lower off, and there's usually not anyone right there to keep an eye on things. Especially if you're using it for climbing multiple laps, or maybe having kids climb on it (who can be notorious for fiddling with anchor hardware), lockers can add a small extra level of security. Personally, I typically use lockers on bolts with a quad/sling for a top rope, but there are many very experienced climbers who do not.

Something to consider: many rock gyms simply have two opposite and opposed snapgate quickdraws at the top of their lead routes. If it's good enough for them, the liability attorneys and the insurance company, it's probably good enough for you too.

And let's remember there's a happy easy compromise in the middle: use one standard quickdraw and one locker draw as shown below. Pretty much no extra equipment and maybe a lot of extra peace of mind.

Remember the law of diminishing returns

A fundamental principle of economics (and many other aspects of life, including anchors) is the law of diminishing returns, which, in econ-speak, means that adding additional factors of production eventually results in smaller increases in output. Say that it takes one builder one year to build a house. So, if you have 365 builders, can you build a house in one day? Of course not, because after a certain point, the extra production (builders) result in lower output (less work getting done because they are tripping over each other).

This can apply to building anchors. Continuing to add “production” (backups, locking carabiners everywhere, etc.) at some point does not significantly increase your “output” (safety margin), so it's probably not so smart to keep doing it. Of course, the question becomes, where do you cross that point? There's no firm answer, but here's one way to think about it mathematically.

Say that the odds of a snap gate carabiner somehow becoming unclipped from an anchor are one in 1,000. The odds of the second leg of the anchor also becoming unclipped is also say one in 1,000. So, the theoretical odds of total anchor failure become 1,000 x 1,000, or one in 1 million. If you're feeling pretty good with these theoretical odds, then you probably don't need lockers on everything.

Closing thoughts . . .

Of course, it's good to know the realistic chances of potential problems and avoid  unrealistic “gear fear”.  However, if there's no penalty in weight, cost, or performance, there's not much downside in adding a small bit of extra security. Is your toprope anchor “overbuilt” with lockers on the bolts? Yeah, maybe. But who cares?

But if someone wants to slam you for making your anchor “overly safe”, then that’s a criticism you can probably live with. Don't let anyone else dictate your level of acceptable risk, regardless of their experience or credentials.

Would you make fun of your grandpa if he wants to wear a belt and suspenders? Picking just one would probably work fine, but if he wants to wear both, so what?

Alpinesavvy strives to offer information and ideas, not advice. I can share my personal preferences, but that in no way implies it's what someone else should do. Choose wisely, amigos!