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Crevasse Rescue Techniques

This is a summary of the crevasse rescue techniques taught by Matt and Zane from Seattle Outdoor Adventurers in spring 2023. Glacier travel and crevasse rescue is an inherently risky activity; use this advice at your own risk.

Sorry, I don't have photos or illustrations to accompany the text descriptions below. Maybe some day.

Required equipment

This equipment is required for the rescue systems described below in addition to your harness, crampons, ice axe, helmet, rope, triple-locking carabiner to tie into the rope, etc.

It is a very good idea to have a fifth locking carabiner, a third Prusik loop, and an extra sling or two to help you fix your system if you make a mistake or run into unexpected complications. A simple pulley (without progress capture) is also good to have.

Terminology

Victim
A person who has fallen into a crevasse or into some other scenario where rescue is required.
Primary Anchor
Whatever is holding the weight of the victim. Depending on the current stage of the rescue process, this may be a person or one or more snow pickets.
Master Point
A carabiner at the end of a picket cable that is used as the primary point to attach the rescue system to the primary anchor.
Victim Line
The rope section leading from the primary anchor to the victim. Regardless of the geometry of the mountain and your situation, the direction along the victim line towards the primary anchor is referred to as up while the direction towards the victim is referred to as down.
Rescue Line
An additional section of rope used in the rescue process that does not carry any load until the rescue begins. This line may be a separate rope or may be part of the same rope as the victim line and is used in different ways depending on the rescue system chosen.
Haul Line
A section of rope, part of the rescue line, that is past the first pulley in the rescue system. It is used in different ways depending on the rescue system chosen.
Catastrophe Knot
A temporary knot (a butterfly knot works well) in the rescue line intended to prevent the rescuer from also ending up in the crevasse if the rescuer slips and its Prusik doesn't hold.

3:1 rescue technique

This section covers a rescue system with a 3:1 mechanical advantage. It assumes a three-person rope team where the person at one end needs rescue (and cannot self-rescue). The person at the other end of the rope is the primary rescuer who is responsible for most of the process below. The person at the middle of the rope is described as the "partner" and helps at various points. In this rescue system, the rope between the rescuer and partner is used as the rescue line.

  1. Arrest!
  2. Once you're stationary, make sure that your partner has the load.
  3. Tie in with Prusik 1 and locking carabiner, then move along the rope to your partner.
  4. Drive a vertical mid-clip picket, making sure that its cable reaches the rope below your partner. Test the picket to ensure that it holds; re-place it as necessary.
  5. Tie the picket's carabiner to the victim line with Prusik 2 below your partner, making sure that the rope is on top of the picket's cable. This carabiner is now the master point.
  6. Get your partner to slowly shift the load onto the picket while staying in arrest position. If the picket does not hold, your partner must re-assume the load and you must re-place the picket. In bad snow conditions, you may need to use a horizontal dead-man anchor.
  7. Plant a horizontal dead-man picket. If you don't have a second picket, you can use your partner's.
    • It should be at least 3 feet (1 m) away from your first picket.
    • Its cable should end one to two feet (30-60 cm) from your master point
    • The two picket cables should meet at an angle of no more than 60 degrees, preferably less.
    Test the picket to ensure that it holds; re-place it as necessary.
  8. Tie the second picket to the master point using a sling, making sure that the rope is on top of the picket cables. Equalize weight between the two pickets as much as possible. Your partner will probably need to fully transfer the load onto the first picket and may need to move a little in order to equalize the pickets properly.
  9. Tie a backup knot in the rescue line, as close as practical to the master point, then clip it to the master point using a locking carabiner. This is to ensure that the rope is secured to the master point if Prusik 2 slips.
  10. Partner releases arrest, ties into the master point with a sling, and disconnects from the rope. Untie the knot that your partner had used to tie into the rope; it will only get in the way.
  11. Self-belay down the rescue line using Prusik 1 to the crevasse edge.
  12. Tie a catastrophe knot in the rescue line past Prusik 1 to prevent further travel down the rescue line if Prusik 1 slips.
  13. Clear excess snow from crevasse edge. Plant your ice axe near the edge so that the victim line passes over its shaft. The idea is to prevent the rope from digging deeply into the crevasse edge, adding friction to your system, and to prevent you from needing to pull the victim face-first through a cornice.
  14. If possible, assess the victim. If the victim can self-rescue, that process can start now. Further steps assume that the victim cannot self-rescue for whatever reason.
  15. Untie the catastrophe knot and self-belay back to the master point using Prusik 1.
  16. Attach a capture pulley to the rescue line between Prusik 2 and the master point, making sure that it allows the rope to be pulled up. Clip the capture pulley to the master point using a locking carabiner.
  17. Remove the backup knot and carabiner from the master point. Untie the backup knot.
  18. Self-belay towards the crevasse edge using Prusik 1.
  19. Attach an ascender to the victim line, making sure that it can move down the rope. Clip it to the rescue line (optional: use a pulley rather than looping the rope around a carabiner). The section of rope between the rescuer and ascender is now called the haul line.
  20. Using Prusik 1, self-belay back to the master point.
  21. Pull in the haul line until the ascender is close to the capture pulley. Your partner makes sure that Prusik 2 doesn't get tangled in the capture pulley as this will be difficult to untangle.
  22. Move the ascender towards the crevasse edge.
  23. Repeat steps - until the victim is at or above the crevasse edge.

6:1 rescue technique

This section covers a rescue system with a 6:1 mechanical advantage. It assumes a two-person rope team with break knots in the rope between the victim and rescuer and that the rescuer is using a second rope (whose length is at least three times the distance between the rescuer and victim) for the rescue; if the rescuer is instead using the free end of the victim rope, the process will be slightly different.

  1. Arrest!. Plant your feet extra well as you will need to take weight off your axe for the next steps while holding the whole load on your feet.
  2. Drive a vertical mid-clip picket, making sure that its cable will reach to your loop on the rope (not only to your belay loop or carabiner). Test the picket to ensure that it holds; re-place it as necessary. Be prepared to resume arrest if needed.
  3. Clip the picket to your loop on the rope (this will be awkward). Be certain that you connected it through the loop rather than around the loop, through your carabiner, through your belay loop, or something else like that as recovery from such a position may be difficult. This carabiner is now the master point.
  4. Transfer the load to the picket. Be prepared to resume arrest if needed.
  5. Tie the rescue rope into the master point using a woven figure-eight loop. This step is unnecessary if you are using the free end of the victim rope as your rescue rope.
  6. Tie into the rescue rope using a Prusik and a locking carabiner to your belay loop.
  7. Tie a catastrophe knot in the rescue rope past your Prusik, leaving yourself some room to move around.
  8. Release yourself from the victim rope.
  9. Plant a horizontal dead-man picket.
    • It should be at least 3 feet (1 m) away from your first picket.
    • Its cable should end one to two feet (30-60 cm) from your master point
    • The two picket cables should meet at an angle of no more than 60 degrees, preferably less.
    Test the picket to ensure that it holds; re-place it as necessary.
  10. Tie the second picket to the master point using a sling, making sure that the rope is on top of the picket cables. Equalize weight between the two pickets as much as possible.
  11. Untie the catastrophe knot and self-belay using the Prusik to the crevasse edge.
  12. Tie another catastrophe knot to prevent further travel down the rescue rope.
  13. Clear excess snow from crevasse edge. Plant your ice axe near the edge so that the rescue line that you will lower shortly passes over its shaft. The idea is to prevent the rope from digging deeply into the crevasse edge, adding friction to your system, and to prevent you from needing to pull the victim face-first through a cornice.
  14. If possible, assess the victim. If the victim can self-rescue, that process can start now. Further steps assume that the victim cannot self-rescue for whatever reason.
  15. Lower a loop of the rescue rope to the victim with a locking carabiner. The victim clips the rescue rope to its belay loop (placing a pulley between the rope and belay loop, if available). If the victim is disabled or otherwise cannot clip into the lowered carabiner, you will need to perform the assistance procedure described below before continuing. The line from the master point to the victim is the rescue line; the line back up is the haul line.
  16. Untie the catastrophe knot and return to the master point using the Prusik.
  17. Attach a capture pulley to the haul line, making sure that it allows the rope to be pulled up. Clip the capture pulley to the master point using a locking carabiner.
  18. Tie in with a Prusik to the haul line (past the capture pulley), then disconnect from the rescue line and remove the first Prusik (or your belay device and clove hitch, if you used the assistance procedure).
  19. Self-belay towards the crevasse edge using your Prusik. Tie a catastrophe knot past your Prusik.
  20. Attach an ascender to the haul line between your Prusik and the capture pulley, making sure that it can move down the rope. Clip it to the free end of the rope (optional: use a pulley rather than looping the rope around a carabiner).
  21. Pull in the haul line until the ascender is close to the capture pulley.
  22. If there is sufficient slack in the victim line, tie a knot in it to take up slack.
  23. Move the ascender towards the crevasse edge.
  24. Repeat steps - until the victim is at or above the crevasse edge.

Other rescue variants

Some other single-victim rescue scenarios that you may encounter include:

If you have two or more victims, good luck!

Self-rescue

This section covers self-rescue from a crevasse. It assumes that you are not seriously injured and are able to move (you need both arms and at least one leg to complete this) and that you have one or more partners on the surface who are able to set an anchor for you. If you are stuck or seriously injured, then wait for your partners to perform either the 3:1 or 6:1 rescue technique. It does not assume that you can reach the crevasse wall.

If you were climbing solo, or your whole team is in the crevasse, or your partner(s) on the surface cut you off, good luck!

  1. Wait for your partner(s) to set an anchor and signal that to you. You do not want to create unnecessary motion on the rope before the anchor is secure. Your partner(s) should also clear away some snow from the crevasse lip and run an ice axe shaft under the rope so that you don't have to climb face-first through a cornice.
  2. Consider hanging your pack and ice axe from a sling so that they dangle below you. This may make it easier for you to clear the crevasse edge once you get there.
  3. Attach an ascender to the rope using a locking carabiner. Hang a 120-cm sling from it and step into the bottom of that loop. Depending on your height, you may need to shorten the sling by looping it around your foot or extend it by girth-hitching it to a Prusik loop (or a 60-cm sling, etc.).
  4. Attach a capture pulley to the rope between yourself and the ascender, making sure that it can move up the rope. Clip the capture pulley to your belay loop using a locking carabiner. If you have difficulty attaching the capture pulley, you may need to put your weight onto the sling to un-load the rope below the ascender.
  5. Pull any slack out of the rope through the capture pulley, then transfer your weight onto it.
  6. Move the ascender higher up the rope then transfer your weight back onto it.
  7. Repeat steps - until there is enough slack between you and the capture pulley to reach the carabiner on the ascender.
  8. Clip the rope through the carabiner on the ascender to create a 3:1 system (optional: use a pulley rather than looping the rope directly through the carabiner)
  9. Pull the slack out of the rope through the 3:1 system, then transfer your weight onto it.
  10. Once you have about 3 feet (1 m) of slack between you and the capture pulley, tie a clove hitch around a locking carabiner below your capture pulley, then clip that to your belay loop. This will stop you if your capture pulley slips. If you already have a clove hitch, pull the slack through it.
  11. Move the ascender higher up the rope then transfer your weight onto it.
  12. Repeat steps - until you are at or above the crevasse edge.

Assisting a disabled victim

If you want to set up a 6:1 rescue system but your partner is unable to clip into a lowered carabiner (unconscious, broken arms, stuck or buried in a position that does not allow the victim to reach its belay loop or the lowered carabiner, etc.), then you will need to descend into the crevasse to assist then ascend back to the surface to resume your rescue. This section describes that process. It assumes that you have followed the 6:1 rescue procedure up to step .

  1. Attach the free end of the rope (which will become the haul line) to your harness so that you do not lose it in the crevasse.
  2. Clip a belay device to the rescue line between your Prusik and the master point, making sure that its gripper is towards you. Do not clip the belay device directly to your belay loop; clip a doubled 120-cm sling (or a long Prusik loop, a 60-cm sling, etc) to the belay device and clip that sling to your belay loop.
  3. Make sure that your Prusik is not long enough to reach your belay device when the sling is fully extended. If it is, replace it with a shorter Prusik.
  4. Remove any catastrophe knots that you have tied in the rescue line.
  5. Tie a clove hitch in the rescue line below your Prusik around a locking carabiner then clip that to your belay loop. This will stop you if your belay device slips. Pull some slack through the clove hitch between it and your Prusik.
  6. Aiming for a point within 3 feet (1 m) to either side of the victim (you do not want to descend directly on top of the victim), lower yourself into the crevasse by sliding your Prusik down the rope; your belay device should block whenever you put tension on the rescue line below the belay device. Pull additional slack through your clove hitch as needed.
  7. When you reach the victim, remove any slack between your Prusik and clove hitch to secure yourself on the rope.
  8. Perform first aid on the victim as necessary
  9. Clip a locking carabiner to the rope below you and the victim's belay loop. It is possible that you will need to partially excavate the victim using whatever tool you have available in order to clip your rope to its harness; be careful to not impale the victim in the process.
  10. Attach an ascender to the rope using a locking carabiner; it must be above your belay device. Hang a 120-cm sling from it and step into the bottom of that loop. Depending on your height, you may need to shorten the sling by looping it around your foot or extend it by girth-hitching it to a Prusik loop (or a 60-cm sling, etc.).
  11. Shift your belay device down the rope and clip its guide loop to your belay loop using a locking carabiner. Pull any remaining slack through the belay device. If you have difficulty shifting the belay device, you may need to transfer your weight onto the sling to un-load the rope below the ascender.
  12. Remove your Prusik; it is no longer necessary and will only get in the way.
  13. Pull additional rope from below (adjusting your clove hitch if necessary) to loop it through the carabiner on the ascender to create a 3:1 system (optional: use a pulley rather than looping the rope directly through the carabiner)
  14. Pull the slack out of the rope through the 3:1 system, then transfer your weight onto it.
  15. Once you have about 3 feet (1 m) of slack between your belay device and clove hitch, pull the slack through the clove hitch.
  16. Move the ascender higher up the rope then transfer your weight onto it.
  17. Repeat steps - until you are at or above the crevasse edge.
  18. At the surface, detach your ascender and foot loop.
  19. Continue to self-belay back to the master point using the belay device and clove hitch.
  20. Resume the 6:1 rescue procedure from step .

References

There are many sources on the Internet and in print that describe crevasse rescue systems, particularly the 3:1 system. They are all slightly different in the equipment that they use and the safety steps that they take. Other references to consider include: