Ensuring Safety And Efficiency With The Right Harness Configuration
Working at height requires an acceptable level of comfort and efficiency to maximise the output from any time suspended on rope.
Using a climbing harness to establish short routes on relatively clean rock can be sufficient considering the time suspended in the harness will be relatively short and the gear loops can suspend some tools. Conversely, the same approach on big walls can work however a full-body harness is not only safer but also more efficient in ascending and descending fixed ropes. Relevant to either approach is the rigging method adopted to fix rope and how the developer will navigate rigging, including others if working as a team on one line e.g. a several hundred metre high wall.
Full Body Harness & Single Rope Technique Rigging
Typically an industrial rope access harness is fully equipped with lanyards, side-mounted rigging bags and a seat to provide the maximum comfort while suspended. This harness and equipment configuration when combined with Single Rope Techniques (SRT) provides the ability to work entirely independently and for the maximum possible output with unlimited rock face accessibility.
Expensive equipment certainly and heavy compared to a basic climbing harness setup but for prolonged suspension, big walls or complicated development (large roofs / routes inside caves) this is the way to work. We use this method regardless of single-pitch roadside or big wall development, routinely averaging 30 installed glue-in anchors per day of any specification and up to a maximum of 65 glue-in anchors installed on easier terrain.
Industrial sit harnesses are well padded for prolonged suspension, have greater back support and feature attachment points with greater load-bearing capacity for tools and haul bags stuffed with rope. Most have integrated chest ascenders that optimise ascending fixed rope whilst supporting an upright posture (of concern if rendered unconscious) and easy attachment loops for a seat. Other features include attachment points for work positioning (versus a single central attachment point on a climbing harness) and a focal connection point made from steel, which alleviates wear created when steel karabiners rub on nylon.
SRT methods rely upon the use of two ascenders, with one normally chest mounted and the other a handled ascender combined with a foot loop that is linked to the central attachment point via a dynamic cowstail. This configuration is called a ‘frog rig or system’ and constitutes the most common SRT configuration. Originally developed by cavers and then adopted by industrial rope access technicians, it is a sit-stand, two cycle ascending system.
When standing up in the foot loop, the chest ascender rises up to the rope (the stand phase), after which one resumes a supported position by the harness (the sit phase).
While there are other ways of configuring ascenders, a pair is always required such that one ascender bears the weight of the person while the other is slid up the rope before becoming load-bearing itself. Frog rigs are the better suited configuration for progressing up and down rigging involving complex ropework i.e. rope re-anchored at multiple points requiring the person to pass knots.
Climbing Harness & Basic Rigging With / Without Backup Rope
A cheaper, simple setup that gets the job done without the expense of a dedicated rope access harness and can be combined with a seat from which to suspend heavier items that harness gear loops are unable to support. This is generally a single-pitch crag option where the rigging is unlikely to involve complex rope work and the time suspended in the harness is not overly prolonged.
Ascenders can be configured:
- ‘Grigri’ style – A Petzl Grigri is combined with a single-handled ascender.
- Jumar style – A pair of handled ascenders each connected by a lanyard.
Developers adopting the ‘Grigri” configuration typically own a Petzl Grigri already and therefore save on buying only one handled ascender and this configuration works well enough on short pitches (despite it not being an efficient method of ascending rope). The down rope end from the Grigri can be passed through a normal karabiner attached to the handled ascender attached above to reduce the effort. When standing up in the footloop, the rope is pulled down through the karabiner with one hand as the other holds onto the handled ascender.
- Rock climbing autolock belay devices are not intended for work at height and therefore lack a ‘hard’ lock function that disables the cam from unintentionally unlocking.
- There is no ‘anti panic’ protection against uncontrolled descent should the user grab the device.
- You are recommended to use a Petzl I’D (or similar product).
The 'Jumar' Method
The 'Jumar method' uses a left and right-handled ascender, linked directly to the climbing harness via separate lengths of dynamic rope and a foot loop is attached to the lower ascender. This provides a minimum of two attachment points in the same way a chest and single-handled ascender will for an industrial rig.
The 'Jumar method' uses a left and right-handled ascender, tied directly to the climbing harness via separate lengths of dynamic rope and a foot loop is attached to the lower ascender. This provides a minimum of two attachment points in the same way a chest and single-handled ascender will for an industrial rig.
The 'Jumar method' is a common big wall ascender configuration however has particular safety disadvantages compared to a 'Frog rig' and that is the potential to shock load either ascender for both are connected via lanyards. The chest-mounted ascender integral to a ‘Frog rig’ moves commensurately with the climber's progress up the rope minimising shock loading should the climber slump back into their harness and the stable position allows for good rope glide.
A lanyard offers more freedom of movement to the user, who can mistakenly find himself above his ascender or with a slack lanyard. This creates the potential for a fall.