Scout's Toolbox Talks

Soil Classification Basics

Toolbox Talk:

What Changes the Soil Type?

June 22, 2025

A trench that was safe yesterday might not be today — soil conditions change fast.

Why It Matters:

Even stable soil can become dangerous after rain, equipment movement, or vibration. If the type changes and no one notices, trench protection may no longer be enough.

Key Points:

  • Rain, freezing, or thawing can break down soil structure.
  • Vibration from nearby work or traffic loosens compacted soil.
  • Excavating nearby or placing heavy loads near the edge changes pressure and risk.
  • The Competent Person must reassess soil anytime conditions change.

Yesterday’s trench isn’t today’s trench. Always reassess after change.

Ask the Crew:

  • Has anything changed that might affect trench safety?
  • When was the last time we rechecked the soil type?