Before you dig, we need to get the basics right.

Trenching is one of the highest-risk activities on any construction site, but most incidents come from missed fundamentals, not unpredictable events.

A safe trench starts before the excavator hits the ground.

1. Assess Ground Conditions

Ground conditions determine how a trench behaves.

Before excavation, assess:

• Soil type (stable, loose, or previously disturbed)
• Presence of water or groundwater seepage
• Nearby loads such as traffic, structures, or stored materials

Even small changes in soil or moisture can significantly increase collapse risk. Every site is different, avoid relying on assumptions from previous jobs.

2. Confirm Depth and Compliance Requirements

Depth matters, but it’s not the only factor.

You should establish:

• Planned excavation depth
• Whether there is a risk of collapse or engulfment
• Applicable safety requirements, including AS 4744.1
• Whether engineered input may be required

Ground conditions, water, and nearby loads all influence what protection is needed, not just depth alone.

3. Choose the Right Trench Protection System

Trench protection should always match site conditions.

Selection depends on:

• Depth and width
• Soil conditions
• External loads
• Installation method

Using the wrong system, or one that is undersized, is a common cause of trench incidents.

If you’re unsure, it’s worth taking the time to choose the right trench shoring system for your project → or review available trench shoring systems for excavation safety → before work begins.

4. Plan Access and Installation

Safe access is essential.

Before excavation:

• Ensure safe entry and exit (e.g. ladders positioned correctly)
• Plan installation and removal of the system
• Confirm machinery can safely handle the equipment

Rushed decisions during installation increase risk. Planning ahead keeps the job controlled.

5. Check Equipment and Documentation

Before anything goes into the ground, check the details.

Make sure:

• All components are present (especially pins and connectors)
• Equipment is in good working condition
• Documentation and certifications are available where required

Small oversights at this stage can create major problems on site.

Final Word

Trench safety isn’t complicated, but it does require discipline.

A few simple checks before digging can prevent serious incidents, reduce delays, and keep your team protected.

Not sure what system suits your job? get expert advice on trench shoring solutions →

For deeper or more complex excavations, review engineering support for trench safety → or [temporary works design for excavation projects → early.