Australian Legislation for Hole and Trenching Excavation

Hole Excavation : Where person is at risk due to excavation​​​​​​​​​​​​​​​​​​​​

Regulation 3.109(1) states
(1) If, at a workplace where excavation work is to be done, any person is at risk of injury because of the excavation work then a person who, at the workplace, is an employer, the main contractor or a self-employed person must ensure that —
(a) suitable barriers are erected between the person at risk and the likely cause of the danger; and
(b) suitable signs that warn of the risk are erected at the place where the excavation work is to be done.
Regulation 3.109 (1) provides for suitable barriers to be erected between the person at risk and the likely cause of danger.
A suitable barrier placed well back from the excavation edge will provide protection for members of the public and some workers.
However, workers inside the barrier near the edge will need some other form of barrier, such as edge protection or shoring of the sides of the excavation.
Many excavations in the metropolitan area, and other areas, are of considerable depth. For example, sewer trenches may exceed a depth of five metres and simple barriers will not provide adequate protection to the public or workers. In these situations, hoardings may be required to provide protection for the public, and careful attention given to the provision of barriers and edge protection needed at the edge of the excavation.
EXCAVATION 23 Regulation 3.109(1) also provides for suitable signs that warn of the risk to be erected where excavation work is carried out. Signs should be placed at appropriate locations around the perimeter of the excavation where they may be easily seen. Signs should comply with the requirements of AS 1319.

Trenching Excavation : Where person is at risk due to excavation​​​​​​​​​​​​​​​​​​​​

Regulation 3.109(2) states
(2) If, at a workplace, there is an excavated area in, around, or across the top of, which persons can move or plant can be moved then a person who, at the workplace, is an employer, the main contractor, a self-employed person or a person having control of the workplace must ensure, as far as is practicable, that —
(a) persons can move safely in, around, and across the top of, the area; and
(b) plant can be moved safely in, around, and across the top of, the area.
24 EXCAVATION

Where there is a risk that persons could fall three metres or more from an edge or face, edge protection consisting of a fall injury prevention system (fall arrest harness and lanyard attached to an anchorage point) or alternatively guard railing consisting of a top rail, mid rail and toe board must be provided in accordance with regulation 3.55. The mid rail may be omitted if a mesh panel is provided with the toe board.​​​​​​​​​​​​​​​​​​​ Further information on the prevention of falls is provided in Section 8.10.