Rope rescue: ASAP and accompanied descent
In case of an accident, a inert person hanging in a harness is a dangerous situation that must be addressed urgently. To act quickly, workers at height must rescue their co-worker on their own, using their standard equipment.
- Read the technical notice before viewing the following techniques.
- It is important to fully understand the information provided in the technical notice before using this complementary information
- Mastering these techniques requires training.
- Consult a professional before attempting to perform these techniques on your own.
This rescue situation is an exceptional case, where the use of single-person equipment for belaying or backing up more than one person is necessary due to the urgency of inert suspension of the victim. The worker must be trained and practiced in this type of rescue.
Downward evacuation is generally the most efficient solution. The rescuer connects himself to the victim, disconnects him from his support and performs an accompanied descent. The descent is controlled with a single descender; see the documents dedicated to the I'D and RIG.
In case the descent rope breaks, possibly due to damage sustained in the initial incident, both rescuer and victim fall onto a backup system. The rope, the ASAP and the energy absorber are loaded very close to their limits of usage: see below for necessary precautions to take.
This document in no way constitutes training in rescue techniques.
Only the performance and limitations of Petzl equipment have been studied.
1) Rescue with a single ASAP, using the ropes in place
If the rescue maneuver must be done on two ropes, one serves as the descent rope, the other as the safety rope.
Only one energy absorber may be used.
Test have shown that the ASAP’SORBER lacks sufficient energy absorption capacity for this usage.
Arresting the fall generates a significant impact load: the rope sheath is torn and several core strands are cut.
Although no complete rope failure was observed during testing, the outcome of performing a rescue maneuver on a few rope core strands is doubtful.
It is preferable to use the ABSORBICA, capable of stopping a two-person fall on an ASAP, up to 250 kg, without damage to the rope.
Tests of ABSORBICA and ASAP’SORBER in this usage:
In 2014, Petzl conducted an extensive series of laboratory tests to determine the limitations of energy absorbers, when used for accompanied descent in a rescue situation.
Depending on the criteria used in their design, different energy absorbing lanyards have different energy-absorbing capacities. Their normal application is single-person fall arrest, for falls of specific length. Rescue and two-person falls greatly exceed this scope.
Tests carried out on the ASAP (models before and after 2013) and ASAP LOCK
Fall using test dummies with harness, on 11 mm diameter low stretch kernmantel rope.
Study of the potential for additional energy absorption by the rope, at a distance from the anchor
In our testing, the trials carried out 3 m from the anchor gave results that were more or less identical to other tests.
On EN 1891 rope, backing up two people with an ASAP + ABSORBICA L57 is authorized in rescue situations with loads up to 250 kg.
Above 250 kg, it is recommended to choose another evacuation strategy.
If two people fall on an ASAP + ABSORBICA L57, the tearing of the absorber will be more significant than with one person.
In this case: clearance = 5 m + rope stretch.
Rescue training: beware of practicing too close to the ground
To avoid the risk of hitting the ground in case of a two-person fall on an ASAP, it is recommended to perform the rescue maneuvers at least 5 m from the ground (more if the rope length implies significant elongation under load).
Before and during the maneuver, make sure that all risks of falling and impact loading are minimized (condition of the ropes in place, risk of anchor failure, pendulum, poorly controlled descent, sudden loading).
2) Rescue with two ASAPs, using additional (emergency) ropes
If the maneuver can be done with one work rope and two safety ropes, it is recommended to use one ASAP and one energy absorber on each safety rope.
ASAP’SORBER and ABSORBICA may be used with this technique.