Typical application of rope access methods in accordance with SOP 43

Transcription

1 Typical application of rope access methods in accordance with SOP 43 This document has been produced to provide practical guidance and illustration relating to some of the key elements of a safe system of work. The document comprises three sections: Section 1 Section 2 Section 3 Anchorage and rigging Rope protection Rescue and rig to rescue Each section includes the relevant excerpt from the IRATA International Code of Practice (ICOP), and practical examples are described and illustrated using photographs. The document is intended to be used as a ready reckoner and is not intended to be exhaustive, nor a substitute for training. The ICOP provides comprehensive and detailed information relating to all aspects of rope access, and is available as a free download at publications.

2 Section 1 Anchorage and rigging Anchor points must be of unquestionable strength and reliability There must be two separate anchors. Often, both ropes are connected to both anchors Excerpt from IRATA ICOP dealing with rope anchor selection and rigging The working line and the safety line are known collectively as anchor lines. Each anchor line should be attached to its own anchor point. The working line and the safety line are normally connected to each other for added security, as well as allowing the anchor lines to be positioned between the anchors. Load sharing between anchors reduces the load on each one. This minimizes the likelihood of failure of either anchor but, in the unlikely event of a failure of one of them, there would only be a minimal impact force on the second anchor. A single element of a structure, (e.g. structural steelwork), a natural geological feature or a tree might have adequate strength to provide a place for anchor points for both the working line and the safety line. This should be verified by a competent person. Supervisors are responsible for checking that the anchor lines are correctly rigged so that if one should fail, a shock load would not be passed on through the system.

3 Section 2 Rope protection measures Hierarchy of rope protection measures Arrange rigging so that the ropes hang directly, with nil or minimum contact with structure Utilise re-belay anchors so that the ropes hang directly, with nil or minimum contact with structure Utilise deviations so that point loading is on the deviation device rather than on the edge or structure e.g. sling and carabiner used as a deviation for routing ropes through grating or a handrail or an edge roller for protecting on edges Use of rope protectors Purpose made heavy duty protectors using materials that offer proven resistance against cuts and heat e.g. steel re-inforced, kevlar Rope protection using equipment adapted for use as a rope protector that offer proven resistance against cuts and heat Traditional canvas rope protectors only to be used as an additional rope protection measure where the rope is in contact with a smooth surface with a radius similar or greater than the rope e.g. a carabiner used as a deviation, an edge roller Excerpt from IRATA ICOP dealing with rope protection measures Anchor line protectors may be used when rigging techniques such as the use of deviations or re-anchors are not possible or appropriate. Rollers offer the best protection at the top edge of a drop, where there is little movement of the anchor line. Heavy-duty carpet (with a high natural fibre content, such as wool) or canvas padding can offer good protection and are commonly used. A single thickness might not be adequate on sharp edges. Anchor line protectors made from polyvinyl chloride (PVC) coated textiles should be avoided due to potential heat caused by friction, which can cause melting of the PVC. The anchor line protection used should ideally ensure that the radius of any bend is at least twice the diameter of the anchor line. For more information on the use of anchor line protectors, see to Appropriate precautions need to be taken to prevent damage to anchor lines, when in use. Wherever possible, anchor lines should be arranged so that they hang free and avoid running over sharp or abrasive edges, or hot surfaces. Where this cannot be done, it is essential that anchor lines are suitably protected, for example, by the use of rollers, edge padding, canvas protectors or other types of anchor line protector While rollers offer the best protection at the top edge of a drop, other types of anchor line protection may be more appropriate in other parts of the descent. See for information on anchor line protectors. Some anchor line protectors have touch-and-close fastening, which is useful when attaching to an anchor line part way down a drop, or to protect lanyards. These anchor line protectors are usually fixed to the anchor line with a thin cord by a suitable knot, e.g. a prusik knot. Another design of anchor line protector simply grips the anchor line by friction to keep it in place.

4 Arrange rigging so that the ropes hang directly, with nil or minimum contact with structure Ropes rigged directly over the work location so that there is no contact with the structure

5 Utilise re-belay anchors so that the ropes hang directly, with nil or minimum contact with structure A rebelay is a second set of anchors used to re- anchor the ropes part way down a drop and can be an effective way of eliminating contact with the structure.

6 Utilise deviations so that point loading is on the deviation device rather than on the edge or structure e.g. sling and carabiner used as a deviation for routing ropes through grating Secondary anchor slings deviate the rope so that the point loading is on a carabiner and not on the structure. Note that rope protectors are used as an additional control measure as there is still the possibility of lateral movement causing contact with the grating

7 Utilise deviations so that point loading is on the deviation device rather than on the edge or structure or a handrail or an edge roller for protecting on edges Handrail used to divert ropes. Note that rope protection is used as an additional precaution.

8 Application of rope protectors When using rope protectors, the use of a single rope protector over both ropes creates a potential single point of failure. With the ropes routed along a slightly different path, and each with a separate rope protector then the single point of failure is removed.

9 Section 3 Rig to rescue Rig to rescue is generally achieved by the use of releasable anchors, so instead of tieing the ropes to anchors using knots, the ropes are connected through devices that can be used to lower or raise the person on ropes. The photograph below shows a simple application rigged for vertical works. Ropes rigged to rescue by connecting through descenders to provide a system that allows the worker to be lowered to the ground.

10 The photograph below show a complex rig to rescue system that enables movement of a casualty both vertically and horizontally A second twin rope system is used to move the worker horizontally One twin rope system is used for moving the worker up and down