1. Excavation
Hazards & Controls

2. Hazards

3. Collapse of sides Type of soil structure is an important factor
What might appear to be a safe soil structure can change dramatically with changes in the weather

4. Hazards - Physical
Materials falling onto people working in the excavation
People & vehicles falling into excavation
People being struck by plant
Undermining nearby structures
Contact with underground services
Access to excavation

5. Hazards - Chemical Fumes from vehicles/plant (C02) Methane/other gases
Contaminated land/previous use?

6. Hazards - Biological Leptospirosis Previous use e.g. hospitals
Drains/sewers
Rubbish and waste

7. Control Measures Tied ladder provides safe access and egress
Guard rails to prevent falls
Poling boards extend above edge to act as toeboards
Exposed services are supported
Supported by timbering and props

8. Collapse of Sides Batter sides and ends
Support with timber, sheeting or proprietary support systems
Use 1.2m as a guide for support, but assess conditions at all times
Even work in shallow trenches can be dangerous, especially if bending or kneeling

9. Materials Falling into Excavations
Do not store spoil or other materials close to excavation – they could fall in or cause sides to collapse
Provide guard rails and toe boards where necessary
Wear hard hat in excavations

10. People & Vehicles Falling into Excavations
Provide guard rails & toe boards (2m)
Use stop blocks to prevent vehicles over-running
Keep vehicles away from excavations wherever necessary

11. People Being Struck by Plant
Keep workers separate from moving plant where possible
Plant operators should be trained and competent
High visibility PPE

12. Undermining Nearby Structures
Make sure excavations do not affect footings of scaffolds or foundations of nearby structures
Provide temporary support for structure if necessary
Surveys of foundations and advice of a structural engineer may be necessary

13. Avoiding Underground Services
Look around for obvious signs of underground services e.g. drains, patching of surface etc.
Use cable locators to trace any services. Mark the ground accordingly
Use service plan
Dig trial holes by hand
Hand dig if in doubt (particularly for plastic cables which cannot be detected)
Have emergency procedures/contact in place

14. Safe Access & Egress Create steps in excavation
Provide good ladder access or other safe ways of getting in and out of the excavation

15. Fumes
Do not site petrol or diesel engined equipment such as generators or compressors in, or near the edge of, an excavation unless fumes can be ducted away or area can be ventilated

16. Protecting the Public
Barrier off all excavations in public places to prevent falls
NRSWA
Where people may get onto the site out of hours, backfill or cover excavations to reduce risks

17. Supervision
A competent person must supervise the installation, alteration or removal of excavation support
People working in excavations should be given clear instructions on how to work safely

18. Inspections Competent person must inspect:
At start of shift;
After any event likely to have affected strength or stability of excavation; and
After any accidental fall of rock, earth and other material.
A written report should be made after most inspections
Stop work if inspection shows excavation to be unsafe