Use of a single climbing line differentiates tree climbing from all other height safety/rope access disciplines. But, unfortunately for the tree care industry, acronyms like DbRT and SRT have muddled our brains!
Aerial arb is the only commercial rope access discipline to work position using a single rope. And, both descriptors, DbRT and SRT, use a single climbing line to complete the task.
Current nonclementure not working
Current tree climbing nonclementure is confusing the issue… and, in doing so, retarding the development of single line climbing for tree work.
Here's an example of the language not working: DbRT or 'Doubled Rope Technique' very quickly becomes 'double rope technique' in the minds of many.
Talk to any rope access guy and they will immediately think in terms of a double rope. That is, two independent ropes - one as the climbing line and one as the backup - a traditional rope access configuration.
We all know this tried-and-true 'double rope' configuration is not practical in tree work and yet the idea persists in the mind of work positioning purists (on safety grounds).
Even seasoned aerial arborists can be fooled into thinking they are climbing on a 'double rope' when using DbRT.
Two lines running overhead, back to the anchor, produce an optical illusion of a 'double rope'. It's only on second thought the climber realizes he is, in fact, on a single line, redirected back on itself via the top anchor or tie-in-point.
The Rope Wrench changed the game
When DbRT first found its way into the aerial arb lexicon SRT (vertical ascent on a single rope á la caving) was pretty much considered an advanced climbing technique. Back then the acronym DbRT worked fine because that was the most common tree climbing configuration.
SRT (a single rope ascent technique with its origins in caving) started out as ascent only in tree work but rapidly migrated to work positioning with the advent of the Rope Wrench. Traditional caving SRT configurations do not allow for safe work positioning during ascent.
By combining the Rope Wrench with a friction hitch 'work positioning' on a single line was suddenly do-able; apparently safe and without a large investment in time or money.
Single line work positioning with the Rope Wrench has proved to be a very efficient (for some trees) and safe (field tested in multiple configurations for at least 18-months without any major incidents).
Consequently, adoption rates for single line ascent/work positioning in tree work have soared.
At this point in time there is no going back for some tree climbers, Single Line Work Positioning is here to stay, forming part of the tree climbers tools kit, right there alongside DbRT (also on a single line).
What does this mean for tree climbing?
In terms of climbing, the aerial arb industry is at a cross-roads.
There is much debate about work positioning on a single climbing line in tree work and yet that is exactly what we do - climb on a single line (as we have always done).
Sometimes the rope is doubled up and sometimes we are climbing on a single leg. Both options can be equally efficient and should form an integral part of the tree climbers tool kit.
Acrimonious acronym wars are counter-productive
If we want to advance the industry it's time to differentiate aerial arb from other forms of height safety/rope access. Let's celebrate single line climbing as a unique tree climbing technique and not play second fiddle to other forms of rope access work positioning.
Current rules, regulation and standards are largely driven by the rope access market but aerial arb has its' own set of unique requirements (subject for a future blog post).
The tree industry cannot expect to have a voice in the wider height safety market if we do not agree on a definition for our tree climbing techniques, confirm and endorse the use of a single rope as an industry standard and find a suitable description for the ascent, descent and work positioning devices we employ in our everyday work!