Alternatives to a PAS

Many climbers choose to forego the PAS (Personal Anchor System) and instead connect themselves to anchors and rappel devices with different methods.

The most common alternatives to a PAS are:

• Using slings
• Using a Purcell Prussik
• Using the rope

Below we discuss these popular alternatives and link to some great how-to videos.

Sewn slings have been around for a long time in climbing. In the days before Personal Anchor Systems existed, the sling was the method of choice for connecting yourself to an anchor or extending a rappel.

The most common method is by passing a sling through the hard points of your harness with a girth hitch (also known as a larks foot) – see the image below. This gives you a static point of connection to attach yourself to an anchor while on a multi pitch climb, belaying a climber from above, or while cleaning an anchor before rappelling and being lowered.

Another use for a sling as a temporary tether is to extend a rappel device away from your belay loop which gives you more space near your harness to connect a backup like a prussik or autoblock. It also keeps the device in your field of view where it is less likely to grab clothing or hair.

There are many advantages to using slings. Many climbers, especially trad/ice/alpine climbers, already have slings for building anchors or extending protection, they are fairly inexpensive, and they come in many lengths and materials. All UIAA/EN rated slings are rated to handle 22kN of force, making them plenty strong, even when we hitch or knot them (which typically reduces their strength by half).

The main disadvantage of a sling is that it is a static piece of gear, meaning it is not designed or tested to have any stretch when it is suddenly weighted or shock-loaded. This can be problematic if a climber finds themselves above an anchor they are attached to and suddenly falls. All of the forces generated by that fall are transferred through static materials like slings, creating potentially hundred of pounds of force on your anchor. This can be especially problematic when hanging on a trad anchor where unlike bolts, we are less sure about the full forces it can handle.

Another disadvantage is they are a fixed length, which can make adjusting the distance from an anchor difficult or impossible. Many climbers overcome this by tying knots along the sling to create ‘pockets’ to clip in shorter or longer as needed, but this has the side effect of creating welded knots that are impossible to untie, making the sling no longer useful for other purposes.

This video from the youtube channel Hard is Easy is one of the most comprehensive breakdowns of slings (and other anchoring methods) that we’ve seen, and the first half fully explains the methods and forces involved when using slings as we have described above.

The pros and cons of using slings instead of a PAS

Named for the Purcell mountain range where it was developed and for the incorporation of a Prissik knot (which is also named for a particular Peak) the Purcell Prussik has seen a surge of use in recent years from rock climbers. Originally developed in search and rescue scenarios, the ‘Purcell’ is technically a piece of a multipart ‘system’ used for ascending, descending, and anchoring using a simple piece of cord. Modern recreational climbing has taken the Purcell Loop part of the system to function as a personal anchor.

One of the biggest advantages of the Purcell Loop is that it can be tied from cord that many multi pitch and alpine climbers are likely to already have on them. AND, because the Purcell is actually a friction hitch, it has the ability to slip a bit as it tightens, making it into a bit of a shock absorber. This shock absorption is also compounded because it is tied from non-static nylon cord which can naturally absorb some forces from a sudden fall as the nylon stretches.

Another big advantage that the Purcell has is that is it adjustable, thanks to the Prussik hitch in the middle, making it a lot more versatile at the anchor than a simple sling.

Drawbacks of the Purcell Prussik as an anchoring solution mainly lie with the knowledge barrier. Though the ‘knot’ isn’t terribly difficult to tie, just like any knot in climbing it definitely takes some practice. If your partner doesn’t know how to tie or operate it, there can also be potential issues if there is an emergency or if you are incapacitated during a climb.

Finally, depending on the cord you use, the Purcell can be nearly as bulky as a PAS, and certainly more bulky than a simple sling. The amount of material you have available can also vary, and without a lot of experience or working it out before you leave the ground, a Purcell can easily be tied too short or too long, which can cause a lot of confusion or unsafe situations fixing it mid climb.

This video from AMGA SPI guide Sarah MacGregor’s youtube channel lead.likeagirl does a great job covering the many ways to tie a Purcell Loop and how it is used at an anchor and for extending rappels.

The pros and cons of using a Purcell Prussik instead of a PAS

The most simple way to attach yourself to an anchor while climbing is by using the rope you are already tied to. It is by far the cheapest and lightest method since there are no additional materials to buy or bring with you. Because of this, it is the preferred method for many multi pitch and alpine climbers who prefer to carry only what is necessary.

Probably the most common way to connect to the anchor using the climbing rope is with a clove hitch knot. There are several ways to tie the ‘clove’, using one or two hands. Once tightened down it is easy to loosen and adjust, making it ideal for anchor stances where you may need to move around, or make room for other climbers to join or pass. You can also tie loops like the figure eight on a bight or the bowline on a bight to connect yourself to an anchor, though these aren’t adjustable.

The rope anchoring method works best when swapping leads on multi pitch climbs, because once the last climber arrives at the belay, the rope can simply be flipped and the belayer is now ready to be placed on belay, undo their clove, and set off leading the next pitch.

Though efficient, light, and quick, using the rope has some downsides. The most notable is that once tied to the anchor, you cannot escape the belay without detaching yourself from the anchor or untying from the rope. If a situation were to happen that would require the use of the full rope, like a stuck rope mid climb, a sudden change in weather requiring descending, or a person in need of rescue, you would need to find an alternative way to anchor yourself so that you could untie from it. You could resort to a sling or cord and anchor yourself as mentioned above, but that would require additional knowledge and equipment that you may or may not have at the moment.

Just like any climbing knot, this method also requires a bit of practice to be smooth and confident, though it is probably one of the easiest to learn. Another downside of this method is that when it comes to rappelling, you can no longer use the rope because it is all hanging below you, meaning that it does not offer a way to extend a rappel as the other methods we have discussed above.

This video from the Seneca Rocks Climbing School shows several methods of quickly attaching to the anchor using the rope in detail.

The pros and cons of using the rope instead of a PAS

In Summary

A PAS can be a convenience for some and an annoyance for others. Some climbers will use a PAS for certain types of climbing (like single pitch sport cragging) but leave the PAS at home for other types (like multi-pitch trad climbing) when weight and space savings matter more.

The most common reasons not to use a PAS are:

• distrust for static materials (ie Dyneema/Spectra) vs semi-static cord or a dynamic rope
• weight savings of not wanting to bring more gear on the climb
• space savings of not wanting to add more gear on the harness
• money savings and preference to use what you already own or to buy cheaper alternatives (like cord or slings)

The most commonly used PAS alternatives (all described above) are:

• Using sling(s)
• Using a Purcell Prussik
• Using the rope