2.5 Tree hazard control measures
2.5 Tree hazard control measures
The following chapter of the manual presents some simple techniques for use where the rescue must be undertaken in a tree with compromised structure . Compromised structure may include pre-existing decay , cracks or other structural defects , or damage that occurred during the accident .
The ability to accurately evaluate the extent of structural defects , and to conduct climbing work safely in heavily compromised trees , is the touchstone of highly competent arborists .
These skills are gained through decades of experience of working with hazardous trees and cannot usefully be communicated on paper . For rescuers , the impact of significant structural defects or damage will be almost impossible to evaluate .
The control measures below are intended to provide an additional ‘ safety margin ’ in otherwise marginal situations , not to be the primary source of security in a tree which would otherwise be inaccessible .
2.5.1 Bracing an anchor point
Bracing is the technique of using additional slings , ropes or MA systems to lift or support a section of tree which has been compromised or will bear a load during rescue operations .
The image below ( repeated from Chapter 1.2 : Tree rescue techniques ), shows two methods to secure a compromised branch whilst performing the rescue . The additional bracing helps to prevent the branch from failing if it is accidentally loaded during the rescue .
Whilst this can be an effective technique , care must be taken that the impact of force on all components in the system are fully understood .
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