Trenching and Excavation Hazards

A cubic yard of soil can weigh as much as a car. In an unprotected trench, that's exactly what can come down on someone with almost no warning — which is why trenching remains one of OSHA's highest-fatality hazard categories, and why it has its own dedicated National Emphasis Program.

Soil doesn't have to look unstable to fail. Vibration from nearby equipment, recent rain, or a trench left open too long can all weaken a wall that looked fine that morning.

Key points

• Every trench 5 feet or deeper needs a protective system — sloping, shoring, or shielding — matched to the soil conditions.
• A competent person has to inspect the trench daily, and again after any rain, vibration, or other change in conditions.
• Keep spoil piles and equipment at least 2 feet back from the trench edge.
• Never enter a trench without a safe way out — a ladder, ramp, or stairway within 25 feet of everyone working in it.
• Watch for underground utilities before digging, and confirm locations before assuming it's clear.
• If a trench looks or feels wrong for any reason, get out and get it reassessed before continuing.

Discussion questions

• Do we know who our competent person is for trench inspections on this job?
• Has anyone worked in a trench that felt unstable, even if it technically "passed" inspection?
• Are our ladders and escape routes actually within reach of everyone in the trench?