Shoring and Shielding Systems Toolbox Talk

Trench walls can collapse suddenly when soil is unsupported, overloaded, wet, or disturbed by nearby equipment. Shoring and shielding systems are used to protect workers, but they only work when they are selected, installed, inspected, and used the right way.

This toolbox talk focuses on safe use of shoring and shielding systems during excavation work. The crew needs to understand the difference between supporting the trench and protecting workers inside it, and when to stop work if the system is not right for the conditions.

Why This Matters

• A cave-in can happen in seconds and can bury, crush, or trap a worker before help can arrive.
• Shoring is designed to support trench walls and help prevent soil movement.
• Shielding, such as trench boxes, is designed to protect workers if soil movement occurs.
• Systems must match the trench depth, soil type, loading, water conditions, and manufacturer limits.
• The competent person must inspect the excavation and protective system before anyone enters.

Common Hazards

• Using a trench box, hydraulic shore, timber shore, or slide rail system that is not rated for the trench depth or soil conditions.
• Allowing workers inside the trench while a shield or shoring system is being installed, removed, or moved.
• Working outside the protection of the trench box or beyond the limits of the shoring system.
• Setting a trench box on uneven ground, large rocks, loose spoil, or unsupported utilities.
• Stacking or modifying shields without following manufacturer requirements.
• Leaving gaps between the protection system and the trench wall that allow soil to fall into the work area.
• Damaged spreaders, bent panels, leaking hydraulic cylinders, missing pins, cracked welds, or loose connections.
• Placing excavators, trucks, spoil piles, pipe, or materials too close to the trench edge.
• Working near crossing utilities where the protective system cannot sit level or fully protect the crew.

Safety Checklist

Before Work Begins

• Have the competent person confirm soil conditions, trench depth, water conditions, and nearby loads.
• Select the correct shoring or shielding system for the excavation and planned work.
• Review manufacturer tabulated data, engineered drawings, or other approved instructions for the system being used.
• Inspect panels, spreaders, pins, hydraulic components, timber, rails, and connection points before use.
• Plan how the system will be installed, moved, and removed without exposing workers to an unprotected trench.
• Confirm safe access and egress inside the protected area.
• Keep spoil piles, pipe, trucks, and equipment set back from the trench edge.
• Identify overhead power lines, swing radius areas, lifting points, rigging needs, and spotter responsibilities.

During Work

• Do not allow workers to enter until the protective system is installed and inspected.
• Stay inside the protected area and do not work beyond the ends of the trench box or shoring system.
• Use the system only within its rated depth, soil, and loading limits.
• Keep the system level, properly connected, and positioned as the excavation advances.
• Do not ride in trench boxes, shields, or shoring systems while they are being moved.
• Check for soil movement, water seepage, falling material, damaged components, or changing trench conditions.
• Maintain clear communication between the operator, spotter, rigging crew, and workers in the trench.
• Reinspect the system after rain, vibration, impact, relocation, or any change in excavation conditions.

Crew Talking Points

• What protective system are we using today, and what is it designed to do?
• What trench depth, soil type, and loading limits apply to this system?
• Where are the safe entry and exit points inside the protected area?
• How will the system be moved as the trench advances?
• Who is spotting equipment and communicating with workers in the trench?
• What damage or movement should be reported right away?
• Ask questions now if the system looks damaged, does not sit correctly, or does not protect the full work area.

Stop Work If

• The shoring or shielding system is missing, damaged, overloaded, or not installed according to instructions.
• Workers are exposed outside the protected area.
• The trench box or shoring system shifts, settles, leans, or becomes unstable.
• Soil cracks, sloughs, bulges, falls, or begins moving around the system.
• Water enters the excavation or weakens the trench walls.
• Required pins, spreaders, braces, hydraulic pressure, or connection points are missing or not secure.
• Equipment, trucks, spoil piles, or materials are too close to the trench edge.
• The excavation conditions no longer match the system being used.

Final Reminder

Shoring and shielding systems save lives only when they are used correctly. Inspect the system, stay inside the protected area, and stop work when the trench conditions change.