Dismantling a tower crane may be difficult and potentially dangerous operation. The relevant precautions given in this section should be observed at all times, particularly in respect of the manufacturer's instructions. It should also be ensured that the correct amount of ballast is in the appropriate position of the crane during all stages of the operation.
With many tower cranes, the dismantling procedure is the reverse of the erection procedure. However, dismantling a crane is more complicated than erecting it because of the space restrictions imposed by the structure which the crane has been used to construct and by the proximity of other buildings. It is essential therefore that the requirements for dismantling and removing the crane are considered at the outset of a project when selecting the type, size and position of the crane to be used.
Equipment used to lower dismantled assemblies should be of adequate capacity to enable these to be lowered to the ground well clear of the building or structure. The equipment including all lifting gear should be tested and thoroughly examined by a competent examiner and carries appropriate test certificates issued by the competent examiner. It is recommended that steady lines are used to steady any load that has to be lowered down from the face of the building and that these are attached before lowering commences.
Whatever procedure and means for lowering are used in dismantling the crane, sections to be dismantled and lowered should be secured to the hook or lifting attachment of the lowering equipment before any bolts or locking devices are released.