Excavation and Trench Safety. Excavation and trenching are amongst the most dangerous operations in the construction industry. Dangers can include cave-ins, falling loads, hazardous atmospheres and hazards from using heavy equipment. Regular pre-work inspections can reduce hazards and serious risk of injury.

1. Excavation Safely
Excavation and Trench Safety. Excavation and trenching are amongst the most dangerous
operations in the construction industry. Dangers can include cave-ins, falling loads, hazardous
atmospheres and hazards from using heavy equipment. Regular pre-work inspections can reduce
hazards and serious risk of injury.
1. GENERAL REQUIREMENTS
• All excavations must be carried out with an approved MS/RA and under a permit to dig arrangement.
• Excavations must be undertaken under the control of a competent person.
• The permit must detail the service detection investigation method utilised by the contractor. A copy of the permit
to dig shall be held by the Supervisor responsible for the work.
• Atmospheric testing shall be undertaken where excavations are in the vicinity of live sewers, where plant and
machinery are nearby or in areas where air flow is restricted.
• Adequate signage, edge protection, barriers and lighting must be installed as appropriate prior to excavation
operations.
• The location of new services must be accurately recorded, with best practice techniques such as tracing tapes or
other devices being used to aid future traceability and help avoid strikes.
2. PLANNING OF EXCAVATIONS
Existing Services, Design, Support and Stability
• No work must be carried out on any live cables or so near as to cause danger. Where it is not practicable to make
the cable dead, all necessary precautions must be taken. Safe digging techniques must be employed by the
contractor and details to divert or protect and mark these services must be put in place. Exposed services/utilities
may need to be supported. Utility bridges/culverts or steel wire rope arrangements must be used to support utility
cables and pipes exposed during excavations.
• The design must be specific to ground conditions (soil sampling may be required) and specify the requirements for
ensuring the stability of the excavation such as sloping or battering the sides, benching and/or shoring.
• Excavations in excess of 1.25 m in depth, and any excavation work adjacent to existing structures, infrastructure,
water courses and live services/utilities require a design by a competent engineer.
• Designs shall consider divergence of any surface water to prevent ingress into excavations and the process for
removing groundwater from the excavation.
3. WORKING IN EXCAVATIONS
A. Excavation Access
Safe access in and out of excavations must be in place. The preferred method of access to excavations or trenches is
by ramps, temporary system staircases, timber stairs, access bridges or equivalent. Use of wailings and struts is not
permitted. Regardless of size, all excavations and trenches must have a minimum of two access points.
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B. Fall Protection
Where persons, plant and/or materials could fall into excavations, pits and holes, or where the collapse of the
excavation sides is a risk, barriers or edge protection must be provided and all edges sloped to suitable
gradients.
Get cable plans and
do mart-outs
Use cable locating
devices
Use safe digging
practices