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Risk Assessment — Excavation up to 1.2 m deep

Document Information

Field Value
Document Reference RA01
Issue Number 2
Issue Date 1 June 2026
Next Review 1 June 2027
Prepared By Sean Ashton
Approved By Aaron Mason, Director

Risk assessment table

Activity / Process Hazard Who / What Affected Existing Controls Pre-control risk Additional controls required Post-control risk
Excavating to repair a main Collapse of excavation Site personnel could be trapped or buried, resulting in serious injury or death At least one operative per team trained in support systems · All excavations supported using sheets, frames, struts or trench boxes · Excavations checked at start of each shift · Weekly inspections by competent person and recorded · Heavy plant prevented from working close to excavation · Personnel avoid working ahead of support 4/2/8 Team to cease work and notify supervisor when excavation exceeds 1.2 m depth · Update excavation inspection records (Supervisor, immediate) 4/1/4
Access/egress to excavation Falls while entering/exiting excavation Site personnel could suffer injuries from falls Ladders used as primary means of access · Ladders in good condition, adequate length, secured to prevent slipping · Ladders positioned at correct angle 3/2/6 Implement inspection-tag system for all ladders (Site agent, within 1 month) 3/1/3
Working around excavations People and objects falling into excavation Site personnel, visitors, members of public could suffer injuries from falls Edge protection with guardrail, midrail and toeboard · Materials stored at least excavation depth away from edge · Working area kept free from materials and clutter 3/3/9 Use excavation support extending 1.1 m above ground as additional edge protection · Implement exclusion zones with physical barriers (Site foreman, immediate) 3/1/3
Unattended excavations Members of public entering work area Members of public, especially children, could fall into excavation All working areas fenced off to prevent public access · Excavations left unattended covered where possible · Area secured using double-clipped open mesh fencing 4/2/8 Ensure additional warning signs are in place · Increase security checks on unattended sites (Site agent, immediate) 4/1/4
Working near structures Damage to adjacent structures Site personnel, visitors, public could be injured by structural collapse. Property damage Temporary works design for excavations near structures · Ensures ground stability and protection of structures 4/2/8 Implement permit system for work near structures · Ensure pre-works survey of adjacent structures 4/1/4
Exposure to contaminated ground Contact with contaminated materials Site personnel exposed to harmful substances through inhalation, ingestion or skin contact Ground investigation prior to works · Appropriate PPE including gloves, respiratory protection if required · Wash facilities provided 3/2/6 Additional staff training on recognising contaminated ground · Improve welfare facilities for decontamination 3/1/3
Working near underground services Contact and damage to services Site personnel could suffer electric shock, burns, gas inhalation or flooding Services identified through plans and CAT scanning · Hand digging within 0.5 m of known services · Services protected once exposed · Appropriate PPE including flame-retardant clothing 4/3/12 Implement service-specific permit to work · Improve availability of insulated tools · Additional service-location training 4/1/4
Dewatering of excavations Sudden ingress of water Site personnel could be injured by flooding. Environmental pollution from pumped water Pumps available for water removal · Silt filtration before discharge · Monitoring of weather conditions 3/2/6 Implement permit-to-pump system for all dewatering · Improve availability of pollution control devices 3/1/3

Notes

  • All excavations must be inspected by a competent person before work commences.
  • Work must cease immediately if excavation depth exceeds 1.2 m.
  • Emergency procedures must be in place for all excavation work.
  • Reference method statements for specific activities as noted in controls.