This article aims to give clear guidelines on what to do when equipping vertical passages during research trips and expeditions, ie. new caves and areas. And not only, even an explored cave and already known vertical pitch require the application of these principles and their proper implementation.
Main principles when rigging vertical pitches
- Approach – start with fixing the rope where it is safe and far from the pitch. When not secured, entering the risk zone* is unacceptable! Scenarios like ‘Just to have a look’, doesn’t mean you can wonder unsecured at the edge of the next vertical passage. Keep in mind that the surface in the caves can be extremely slippery and often with loose stones and rocks.
*a risk zone here refers to a place where slip, trip, fall or other that disturbs your balance and safety may have a serious or even fatal outcome. - Cleaning the pitch – as the person who riggs you have a unique opportunity to clean the vertical of unstable stones and rocks. Your responsibility here is enormous. Thoroughly check the way down using your hands, feet and hammer.
- Rigging a line away from water – any system must be away from an instantaneous flow or unusually high flood conditions. Rising water in combination with a system near the water is a prerequisite for accidents or simply inability to pass.
- Checking the rock – check the rock with a hammer before placing an anchor. Only a rock hammer can give you information whether the chosen natural support is stable and whether the rock can ‘bear’ a given anchor (anchor, spit or other). Visual inspection is often misleading! Look for the ‘right’ sound of the rock.
Primary and secondary anchor points – common mistakes and misunderstood concepts
Distance between the knots of primary and secondary anchor points
The biggest distance between the knots of primary and secondary anchor points is 1m
Reason: H0 applies, more about the concept you can read in ‘’ABV tehnika na edinichnoto vuze”, pages 25 and 26.
Distance between the anchor points
When putting anchor points, the smallest distance between two expansion bolts is 20cm. For spits the distance is bigger, i.e. 30cm.
Reason: when placing an anchor point on the rock, forces apply, for different types of anchors the forces are different. This rule is intended not to overload the rock in the section you selected. These distances are taken from the tests of the Italian Rescue Service – CNSAS, and an additional distance is provided as the tests are done in ideal conditions. The data is published in the Croatian book Speleologija, p. 296 and 297
What is the distance between the expansion bolts here?
Rebelay
If the rebelay is at less than 5 m from the primary and secondary anchor points, then for this rebelay must be applied a secondary anchor point.
The reason: If the rebelay is at less than 5 m, if there is failure with the same rebelay, we aim for the highest falling factor to be 0.2.
For permissible fall factors with static ropes see:
- ”ABV tehnika na edinichnoto vuze’, p. 37 i 38
- Alpine Caving Techniques, p. 55
- Osnovni parametri na statichnite vuzeta, Konstantin Kasabov here
Calculating the fall factor when rebelay fails
Approach
Basically, when approaching a vertical pitch we treat the applying of primary and secondary anchor points as a rule.
The reason: even when approaching, failure of an only anchor point can be fatal. See the PETZL article here.
When the approach is rigged with one anchor only, simply re-rig
Pendulum
After a pendulum, which makes a significant deviation from the main line of the system, the rebelay needs to be applied to the secondary anchor point.
The reason: if a single rebelay anchor point fails, the force can cause damage or cutting of the rope, as well as serious injuries to the speleolog who is rigging.
Big pandulum without secondary anchor point
Traverse line
Traverse line starts and ends with primary and secondary anchor points. The reason: we treat the first and the last anchor points as primary secondary points and each primary anchor point must be secured by a secondary anchor point each.
The approach is rigged using primary and secondary anchor points
Summary
The style of rigging is a matter of taste, the safety element must be uncompromising. The question we have to ask ourselves when rigging is what if …? What if the anchor point fails, what if the water level rises suddenly, etc. This will help you make informed decisions, ie. to know what and why you do it.
“From experience, I can say that you can reduce the risk by following normal safety rules and your common sense.”
Pavel Demidov, 2020, the whole interview of Pavel is here
Text: Tsvetan Kosturkov
Sources:
- Alpine Caving techniques, Marbach G. & Тоurte B., 2002, Speleo Projects, Caving Publications International
- ABV tehnika na edinichnoto vuze, Nedkov P., 1983, Sofia
- Speleologija, many authors, editor Rnjak G, 2019, Zagreb
- Techniques for equipping a pit, PETZL https://www.petzl.com/INT/en/Sport/Techniques-for-equipping-a-pitch?ActivityName=Caving
- Osnovni parametri na statichnite vuzeta, Kasabov K., 2012, Pod RB, https://pod-rb.eu/blog/2012/10/29/%d0%be%d1%81%d0%bd%d0%be%d0%b2%d0%bd%d0%b8-%d0%bf%d0%b0%d1%80%d0%b0%d0%bc%d0%b5%d1%82%d1%80%d0%b8-%d0%bd%d0%b0-%d1%81%d1%82%d0%b0%d1%82%d0%b8%d1%87%d0%bd%d0%b8%d1%82%d0%b5-%d0%b2%d1%8a%d0%b6%d0%b5/