Excavation and trenching work remains one of the most hazardous activities in the construction industry. OSHA’s trenching and excavation standards under 29 CFR 1926, Subpart P have been in effect since 1989 and are consistently among the agency’s most frequently cited standards. Cave-ins are the leading cause of excavation fatalities, and OSHA maintains a national emphasis program specifically targeting trenching and excavation hazards. The standard requires a competent person to inspect excavations daily, classify soil, select protective systems, and take immediate corrective action when hazards are identified. This guide covers all inspection requirements with a free downloadable checklist.
Free Excavation & Trenching Inspection Checklist
Download our Word document checklist covering soil classification, protective systems, access/egress, atmospheric monitoring, and adjacent structures per OSHA Subpart P.
Download Checklist (.docx)Regulatory Framework
OSHA 29 CFR 1926 Subpart P — Excavations
- 1926.650: Scope, application, and definitions. Applies to all open excavations made in the earth’s surface, including trenches. Defines competent person, excavation, protective system, shield, shoring, and other key terms.
- 1926.651: Specific excavation requirements including surface encumbrances, underground installations, access/egress, vehicular traffic exposure, falling loads, water accumulation, adjacent structure stability, and daily inspections by a competent person.
- 1926.652: Requirements for protective systems. Mandates sloping, benching, shoring, or shielding in excavations 5 feet or deeper (unless in stable rock). Excavations 20+ feet require a system designed by a registered professional engineer.
- Appendix A: Soil classification system defining Stable Rock, Type A, Type B, and Type C soils based on unconfined compressive strength and visual/manual testing.
Related Standards
- 1926.651(b): Underground utility location required before excavation. Contact 811 (national call-before-you-dig) at least 48–72 hours before excavation begins.
- 1926.651(g): Atmospheric testing required in excavations where hazardous atmosphere exists or could reasonably be expected (near landfills, gas lines, hazardous substance storage).
- 1926.651(j): Adjacent structures must be supported or undermined areas must be protected if excavation could affect their stability.
- OSHA NEP: OSHA maintains a National Emphasis Program on Trenching and Excavation, authorizing programmed inspections of excavation work regardless of complaint status.
Cave-in fatality risk: A cubic yard of soil weighs approximately 2,700 pounds. Workers buried under even a small amount of collapsed soil face a high risk of suffocation and crush injuries. An unprotected trench can collapse without warning. Never enter an unprotected excavation 5 feet or deeper. OSHA can issue willful citations with penalties up to $161,323 per violation for excavation safety failures.
Part 1: Pre-Entry & Soil Classification
| Inspection Item | What to Check |
|---|---|
| Competent person on site | A designated competent person per 1926.650(b) present on site. Individual can identify existing and predictable hazards and has authority to take immediate corrective action including stopping work and removing workers. Competent person trained in soil classification and protective system selection. |
| Soil classification | Competent person has classified soil per Appendix A using at least one visual and one manual test. Classification documented. Soil type recorded: Stable Rock, Type A (1.5+ tsf), Type B (0.5–1.5 tsf), or Type C (below 0.5 tsf). Previously disturbed soil never classified as Type A. Soil conditions reassessed after rain, flooding, or changing conditions. |
| Utility location | One-call notification (811) made at least 48–72 hours before excavation per 1926.651(b). Utility locations marked on site. All underground installations (gas, electric, water, sewer, telecom) identified. Hand digging or soft digging within tolerance zone of marked utilities. Utility owner response documented. |
| Surface conditions | Surface encumbrances (trees, utility poles, signs, boulders) removed or supported per 1926.651(a). Surface water and runoff diverted from excavation edge. Spoil pile set back at least 2 feet from excavation edge per 1926.651(j)(2). Adjacent roadways and structures evaluated for stability impact. |
| Excavation permit | Excavation permit issued (if required by company or jurisdiction). Permit documents location, depth, soil type, protective system, competent person, emergency contacts. Duration and scope of work defined. Permit reviewed and signed by competent person before work begins. |
Part 2: Protective Systems & Access/Egress
| Inspection Item | What to Check |
|---|---|
| Protective system installed | Appropriate protective system in place for excavations 5+ feet deep per 1926.652. System matches soil classification: sloping/benching angles per Appendix B tables, shoring designed per Appendix C/D, or shielding (trench box) rated for soil type and depth. System extends from 2 feet above bottom to top of excavation or to finished grade. |
| Sloping/benching | Slope angle correct for soil type: Type A – 3/4:1 (53°), Type B – 1:1 (45°), Type C – 1-1/2:1 (34°). No undercutting at toe of slope. Benches properly formed and dimensioned. Slope face stable with no cracking, sloughing, or bulging. No surcharge loads (equipment, materials, spoil) within the slope failure zone. |
| Shoring | Shoring system properly installed per manufacturer specifications or engineer design. Hydraulic cylinders pressurized and locked. Uprights and walers bearing against soil. No gaps between shoring and excavation walls. Shoring extends above excavation as required. Timber components free of defects and properly sized per Appendix C. |
| Shielding (trench boxes) | Shield rated for the depth of the excavation and soil type. Shield extends at least 18 inches above surrounding ground or spoil pile. No more than 2 feet of excavation below shield bottom. Shield properly backfilled to prevent lateral movement. Workers not permitted in shield during installation, removal, or lateral movement. Shield not damaged, bent, or corroded beyond manufacturer limits. |
| Access and egress | Structural ramps designed by competent person (if over 20 feet, by registered PE). Ladders, stairways, or ramps within 25 feet of lateral travel for all workers in excavations 4+ feet deep per 1926.651(c). Ladders extend at least 3 feet above edge of excavation. Access points not blocked by equipment or materials. |
Part 3: Hazards & Ongoing Monitoring
| Inspection Item | What to Check |
|---|---|
| Atmospheric hazards | Atmospheric testing performed where hazardous atmosphere exists or could reasonably be expected per 1926.651(g). Oxygen levels between 19.5% and 23.5%. Flammable gas below 10% LEL. Toxic gas levels below applicable PELs. Continuous monitoring if hazardous atmosphere detected. Ventilation provided as necessary. Emergency rescue equipment available. |
| Water accumulation | No water accumulating in excavation unless controlled per 1926.651(h). Water removal equipment monitored by competent person. Diversion ditches, dikes, or dewatering pumps functioning. Workers protected from hazards caused by water accumulation. Safety harness and lifeline provided if water poses drowning hazard. |
| Adjacent structures | Adjacent buildings, walls, sidewalks, and pavements evaluated for stability per 1926.651(i). Support systems (underpinning, bracing) installed where excavation could affect stability. No undermining of foundations without engineered support. Monitoring for settlement, cracking, or movement of adjacent structures. |
| Vehicular traffic | Workers exposed to vehicular traffic wearing high-visibility warning vests per 1926.651(d). Barriers or barricades protecting excavation from traffic. Stop logs or barriers at excavation edges where mobile equipment operates. Signage and flagging directing traffic away from excavation zone. |
| Daily inspection | Competent person inspecting excavation daily before start of work per 1926.651(k)(1). Inspection after every rainstorm, freeze-thaw cycle, or other hazard-increasing occurrence. Evidence of potential cave-ins, protective system failure, or hazardous atmospheres documented. Workers removed from excavation until unsafe conditions corrected. |
Soil classification quick reference: Stable Rock: solid mineral matter, can be excavated with vertical sides. Type A (1.5+ tsf): clay, silty clay, sandy clay, clay loam — never fissured or previously disturbed. Type B (0.5–1.5 tsf): angular gravel, silt, silt loam, sandy loam, previously disturbed Type A. Type C (below 0.5 tsf): gravel, sand, loamy sand, submerged soil, soil from which water is freely seeping. Visual tests: observe soil during excavation for cracking, spalling, raveling, sloughing. Manual tests: thumb penetration, pocket penetrometer, ribbon test, dry strength test.
Download the Free Checklist
Get our excavation and trenching inspection checklist in Word format. Covers all Subpart P requirements for competent person daily inspections.
Download Checklist (.docx)Go digital with Ecesis. Document excavation inspections in real time with Ecesis inspection software. Capture soil conditions, protective system status, and atmospheric readings on any mobile device. Track competent person assignments and daily sign-offs. Generate OSHA-ready inspection records automatically. Request a free demo.
Ecesis EHS Software
Inspections
Daily excavation inspections with soil classification, protective system verification, and photo documentation.
Incident Management
Report near-misses, cave-in events, and utility strikes with root cause analysis and corrective actions.
Compliance Calendar
Track excavation permits, 811 utility locate requests, and equipment inspection due dates.
Task Management
Assign corrective actions for protective system deficiencies and track completion.
Safety Observations
Document safe and at-risk behaviors during excavation work for trend analysis.
Training
Track competent person training, excavation safety courses, and equipment operator certifications.
