⛏️ Excavation Safety Playbook
Daily excavation inspections protect workers from cave-ins — the leading cause of death in trenching work. A competent person must inspect before entry, after rain, and whenever conditions change.
Why This Matters
| Without Daily Inspection | With Daily Inspection |
|---|---|
| Cave-ins kill without warning | Protective systems verified before entry |
| Soil conditions change (rain, vibration) | Re-inspection after any change |
| Damaged shoring goes unnoticed | Shoring condition checked every day |
| No documentation of due diligence | Inspection records prove compliance |
| OSHA finds deficiencies first | You find and correct first |
Cave-In Risk
One cubic yard of soil weighs about 3,000 pounds. A cave-in can bury a worker in seconds. There is no time to react — inspection must happen before entry.
Roles and Responsibilities
| Role | Responsibilities |
|---|---|
| Competent Person | Inspect excavations daily; classify soil; select and verify protective systems; have authority to remove workers |
| Superintendent | Ensure competent person is designated and inspections occur; support corrective actions |
| Foreman | Report condition changes; ensure workers don't enter until inspected; implement corrective actions |
| Workers | Do not enter until released; report water, cracks, or changes; use designated access/egress |
Competent Person: Qualifications and Duties
Competent person = one who can identify hazards and has authority to take corrective action.
| Requirement | Detail |
|---|---|
| Training | OSHA 1926.32(f): trained in soil analysis, protective systems, confined space (if applicable) |
| Authority | Must be able to remove workers and stop work when hazards exist |
| Availability | Must be on-site or readily available when excavation work is performed |
Daily Inspection Requirements
Inspect before employee entry and when:
| Trigger | Reason |
|---|---|
| Start of each shift | Conditions change overnight |
| After rain, storm, or thaw | Water weakens soil; freeze/thaw destabilizes |
| After any change in conditions | Adjacent load, vibration, utility strike |
| After blasting or heavy equipment near edge | Vibration can compromise soil |
Soil Classification
| Type | Visual/Manual Test | Slope Angle (if sloping) |
|---|---|---|
| Type A | Cohesive, high compressive strength; dry, unconned | ¾:1 (53°) |
| Type B | Cohesive, moderate strength; previously disturbed, angular | 1:1 (45°) |
| Type C | Granular, no cohesion; submerged, soft | 1½:1 (34°) |
When in doubt, treat as Type C. Perform manual tests (thumb penetration, plasticity) per OSHA Appendix to Subpart P.
Protective System Verification
| System | What to Check |
|---|---|
| Sloping | Slope angle matches soil type; no undercutting; no tension cracks |
| Shoring | Members intact, properly installed, no deflection; hydraulic shores within spec |
| Shield (Trench Box) | Rated for depth; properly set; no damage; no riding in box during installation |
| Combination | All components compatible and correctly installed |
Access and Egress
| Requirement | Detail |
|---|---|
| Ladder/ramp | Within 25 feet of workers in trench 4+ feet deep |
| Stability | Extends 3 feet above landing; secure at top |
| Multiple entries | For trenches 4+ feet, ensure ready egress |
Spoil Pile and Utilities
| Item | Requirement |
|---|---|
| Spoil pile distance | Minimum 2 feet from edge (more for unstable soil) |
| Utility location | Verify 811/call-before-you-dig; hand dig within tolerance (often 24–36 inches) |
| Support | Exposed utilities supported per engineer specs |
Water and Adjacent Structures
| Hazard | Action |
|---|---|
| Water accumulation | Pump or divert; evaluate effect on slope stability; re-inspect after dewatering |
| Adjacent structures | Evaluate undermining risk; use support systems if needed |
| Adjacent loads | Surcharge from equipment, spoil, or materials — increase setback or shore |
Inspection Documentation Workflow
- Before entry — Competent person walks the excavation
- Checklist — Soil type, protective system condition, access/egress, utilities, water, spoil
- Document — Date, time, location, findings, corrective actions if any
- Release — Workers may enter only after inspection passes
- Re-inspect — After any trigger (rain, change, etc.)
Daily Inspection Checklist Summary
| Item | Check |
|---|---|
| Soil type | Classified; slope/shorings match |
| Protective system | No damage; properly installed |
| Access/egress | Ladder within 25 feet, secure |
| Spoil pile | 2+ feet from edge |
| Utilities | 811 called; hand dig within tolerance |
| Water | None accumulating; or pumped with stability verified |
| Adjacent loads | Equipment/material setback adequate |
BLDR Pro Integration
Use BLDR Pro to document daily excavation inspections. Attach photos of soil conditions, protective systems, and access points. Tag locations for easy retrieval during OSHA visits or incident investigations. Store inspection checklists and competent person sign-offs. When a cave-in occurs or OSHA arrives, your documentation proves you inspected — and when.
Metrics to Track
| Metric | Target | Frequency |
|---|---|---|
| Inspections completed vs. excavation days | 100% | Daily |
| Deficiencies found | Log all | Per inspection |
| Correction time (deficiency to fix) | Same day for critical | Per deficiency |
| Competent person availability | 100% when excavating | Daily |
Common Mistakes
| Mistake | Problem | Fix |
|---|---|---|
| Skipping inspection when "it looks fine" | Conditions change; looks can deceive | Inspect every day, every time |
| No re-inspection after rain | Water dramatically weakens soil | Re-inspect after any precipitation |
| Ladder too far away | Worker can't escape in time | Ladder within 25 feet, always |
| Riding in trench box during install | Fatal crush hazard | No one in excavation during box placement |
| Undercutting the slope | Destroys protection | Maintain slope angle; no digging under |
Troubleshooting
"We can't get a ladder in the trench"
- Install ladder before work begins. Ladder must be part of the pre-entry setup. If the trench is too narrow, the protective system may need adjustment.
"Soil type changed mid-excavation"
- Re-classify. You may need to change slope angle or add shoring. Update the inspection and protective system before continuing.
"Subcontractor is excavating without our inspection"
- GC's competent person or designated person must inspect before any worker entry. Establish this in the contract and daily coordination. Audit sub excavations.
"Water keeps filling the trench"
- Pump continuously; ensure discharge doesn't flow back in. Evaluate whether work can proceed safely. Consider whether it's Type C soil when wet.
"Competent person is on vacation"
- Excavation work cannot proceed without a competent person. Designate a backup who is trained and authorized. Plan coverage before the competent person is absent. Document the designated competent person for each shift.
Related Resources
| Resource | Link |
|---|---|
| Trenching Toolbox Talk | Trenching Safety |
| Site Safety Inspection Playbook | Site Safety Inspections |
| JSA/JHA Playbook | JSA/JHA Process |
| OSHA Excavation Standard | OSHA 1926 Subpart P |