Any work that concerns building demolition or the demolishing of a structure is classified as "construction work" according to the Work Health and Safety (WHS) regulations.

Any requirements for construction work must be complied with, including regulations concerning an engineering survey.

The Code of Practice that determines how to manage risks to health and safety in demolition work is an approved code under section 274 of the Work Health and Safety Act (WHS Act). It has been developed by Safe Work Australia and applies to all types of demolition work. Included in this Code of Practice are recommended courses of actions, as well as legal imperatives to do with demolition work, included the engineering survey requirements.

Demolition contractors, even if just involved in house demolition, must aim to minimise all risks, removing whatever hazards are practical to eliminate. This element comes into play in the initial design of the building. So far as it is reasonably practicable, designers must ensure that the structure is designed to be without risks to the health and safety of persons in relation to the proper demolition or disposal of a structure. In other words, it should be built into the design of the structure how to most safetly demolish it. There should therefore be documentation for the safe demolition of any structure. These demolition specifications and procedures should be created with the application of acceptable engineering principles and published technical standards.

If this documentation is unavailable, or the structure has been damaged or weakened (by fire or deterioration for example) then a qualified structural engineer, or an otherwise competent person, should conduct an engineering investigation and deliver an engineering investigation report. This is essentially an engineering survey of the structure that should be conducted before demolition occurs.

Some issues that should be considered in the engineering investigation:

• Identifying the structural system involved.
• Searching for engineering details specifying size, type and configuration of key structures and materials,and locating any applicable documents.
• Assessing the load-carrying capacity of the structure (including strength requirements, degradation of original materials and capacity to sustain superimposed loads).
• Verifying composition or quality of structural components.
• Assessing the loss of structural strength that has resulted from destructive investigation methods.
• Any structural irregularities resulting from floor penetrations (including the identification and location of them).
• Assessing proposed methods and sequence of demolition, ensuring there is minimal risk of unpremeditated collapse of the structure.
• Identifying any other details that may concern demolition contractors or an excavator with regards to strength, construction or contents.

Note that if the demolition involves an element of the structure that is load-bearing or is related to the physical integrity of the structure, the work is then considered to be "high risk construction work". In this case, a Safe Work Method Statement (SWMS) must also be prepared before the construction work begins.

The SWMS must:

• identify the type of high risk construction work being conducted
• specify any risks and hazards to health and safety
• describe how risks are being controlled, including implementation, monitoring and review, and
• be developed with input from workers and representatives who are carrying out the work itself.

It is important that you follow the Code of Practice for any demolition work that is carried out. Ensure you have read the Code of Practice for Demolition Work, as well as the Code of Practice for Construction Work before you begin. Designers should also read the Code of Practice: Safe Design of Structures for further information on how to design structures for safe demolition.