To facilitate horizontal or diagonal movement across a rope system, ropes can be tensioned between two sets of anchors. If you’re using a diagonal tensioned line, you’ll also need to use additional working and safety lines to control movement as you cross.

An important goal when rigging a tensioned line, is to rig it so that the load is evenly shared between both anchors on each side. Tensioned lines that work by evenly distributing the weight of what they’re carrying between them, will minimize uneven loading in the system. This will prevent unnecessary wear or stress on your equipment (adding to its longevity), and also make the system easier (and safer) to control/manoeuvre.

Although we refer to this rigging technique as a ‘tensioned line’, you’ll actually want to minimize the tension that is put on the ropes and anchors as much as possible. Identify the tension you need for the system to work, and don’t exceed it. Over-tensioning a system minimizes the amount of energy absorption in the rope by using up the stretch potential before a load is even applied. While this may reduce the sag in the system, this leads to a higher angle across the span of the line. The higher this angle, the higher the load on the system becomes. We recommend taking this into account, if you can not get high enough without cranking your line up to 150 degrees, consider another method.

During your IRATA Assessment, L2 and L3 certifying techs will be asked to demonstrate competence rigging tensioned lines at any positional angle.

Your assessor will specifically be watching to make sure that you…

• Minimize the length of back-up lanyards (the smaller their length, the shorter the fall distance -- minimizing the impact load that would result from equipment failure).
• Control movement -- specifically if using a diagonal tensioned line.
• Consider a rescue plan (using releasable rigging at one or both ends of the tensioned lines is one option, which you’ll be encouraged to consider).

There isn’t just one way to rig a tensioned line – IRATA assessors recognize a variety of methods as being acceptable (which we’ll cover during your training week).

Additional resources to check out:

TACS 6.4.12 for the source material for this blog.

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This is part of an ongoing series, where we’re breaking down IRATA’s syllabus and clarifying exactly what ‘demonstrating competence’ and ‘demonstrating awareness’ means, and what will be expected of you on assessment day. As an IRATA L2 certifying tech, you’re expected to be fully competent with the L1 Syllabus. To return back to the IRATA L2 Study Guide or IRATA L3 Study Guide, click below: