4 . Pre-demolition Surveys
Engineering surveys should be carried out prior to commencement of demolition work . Engineering surveys should include structural stability , existing services and the presence of hazardous substances .
In assessing the structural stability of the building or structure to be demolished , the Safe Working Load ( SWL ), taking into account debris accumulation , weight of machinery and / or other anticipated dead and live loads , should be determined by a Professional Engineer . Caution should be taken to ensure that floors are not loaded up to a level which exceeds the SWL . Precautionary measures include ( but not limited to ) the use of steel ramps , limiting the level of accumulation of debris , etc . Where demolition work would render floors , walls and other structural elements unstable , adequate shores and / or braces should be installed .
Steel ramps .
Effort should be taken to identify , from as-built drawings , if asbestos-containing materials are present in the building ( s ) / structure ( s ) to be demolished . If unsure , it should be assumed that asbestos-containing materials are present , or an asbestos survey can be conducted to ascertain that the building / structure to be demolished does not contain asbestos ( refer to the section on Asbestos Management on page 11 ).
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