Type C soil is the most dangerous — it includes sand, gravel, saturated soils, and anything previously disturbed.
Why It Matters:
Most trench fatalities happen in Type C conditions because walls can collapse without warning — sometimes within seconds.
Key Points:
- Type C requires the strongest protection — trench boxes, wider slopes, or benching are mandatory.
- Don’t trust “just a quick task” — even brief exposure is dangerous.
- Wet, granular, or reworked soils automatically default to Type C.
- A Competent Person must confirm the classification before work begins.
✅ Type C = Highest Collapse Risk. Don’t take shortcuts.
Ask the Crew:
- Are we working in Type C today?
- Do we have the right protective system in place?