Snatch rescue — casualty in descent mode

Rescue carried out from below

Ascend the casualty's safety rope with your back-up device on the casualty's working rope.
Upon reaching the casualty, place them in as near an upright position as possible without endangering the casualty further. This may be achieved by temporarily placing a loop from one side of the chest harness over the top of the descender device.

ABC of first aid
The rescuer should consider the ABC of first aid (Airway, Breathing, Circulation), and deal with the casualty's condition in the strict order of: Breathing, Bleeding, Bones.
Using a 2nd back-up device, place it above the casualty and move the original back-up above the casualty, removing the secondary back-up.
Continue ascending 0.5 m above the casualty and change into descent mode.
Remove the casualty's back-up device from the rope.
Make an attachment from your descender device carabiner to the top of the casualty's chest ascender or the sternal attachment on the harness, with a short sling or chain of 2 or 3 carabiners.
Operate the casualty's descender to lower him/her onto the short sling or chain of carabiners and then remove it from the rope.
Before unlocking your descender, employ a braking carabiner to create additional friction. Descend slowly in a controlled manner, avoiding any jerky movements that could shock-load the system, and employing good casualty management.

Your instructor will demonstrate a number of methods of carrying out the above manoeuvres dependent on the type of harness and descender device being used.

Rescue carried out from above

Descend the casualty's safety rope with your back-up device attached to the casualty's working rope.

Loaded safety rope
If the safety rope is loaded, 'reverse prussik' down the rope — and see the section on de-weighting the back-up device.
Upon reaching the casualty, lock off your descender device and place the casualty in as near an upright position as possible.
Make an attachment from your descender device carabiner to the top of the casualty's chest ascender or sternal attachment, with a short sling or chain of 2 or 3 carabiners.
Remove the casualty's back-up device from the rope and use this cow's tail to make a second attachment to the main attachment point on your harness. Alternatively, use your own long cow's tail and attach this to the casualty's main attachment point on their harness.
Operate the casualty's descender to lower him/her onto the short sling or chain of carabiners before removing his/her descender device.
Continue with the rescue as described above.