Stationary boom high point
In densely branched trees it may not be possible to access the casualty directly with the rescue basket due to impeding branches . In these cases , the rescue boom or other crane-capable EWP can be used to position a high point directly over the casualty . Once installed , the ropes and high point can be used to perform a rope-based rescue using a variety of individual or team-based rescue archetypes , including a ground-based rescue in some circumstances .
In the image above , an adjustable haul system and belay device have been installed between a suitable anchor and a redirect pulley placed on the outrigger leg of the rescue boom . This will allow the ground team to assist with either lifting or lowering the casualty if needed . The redirect pulley must be in the same vertical plane as the boom to avoid side-loading the boom .
Note that the ropes could be attached directly to the crane point below the bucket if the lifting and lowering capacity is not required or if a suitable ground anchor is not available . This method reduces the magnitude of force on the basket but loses the ability for the line to be belayed from the ground .
Skills that may be required : Technique
Description Stationary boom high point Pg . 62
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