Work in a Trench or Shaft Deeper Than 1.5 m

Why this is high risk construction work

A collapsing trench buries a worker in seconds and a cubic metre of soil weighs over a tonne, so cave-in is often fatal. The depth trigger reflects when collapse becomes deadly.

Because it is one of the 18 high risk construction work categories, a SWMS is legally required before the work starts (your state's WHS Regulations, provision 299; s 299 in NSW), not a nice-to-have.

The controls a SWMS should set out

In hierarchy of controls order, highest first:

• ✓ Prevent collapse: bench or batter the walls, or shore with a trench box where space is tight
• ✓ Locate underground services before digging (Dial Before You Dig, potholing)
• ✓ Safe access and egress within 9 m of any worker
• ✓ Keep spoil, plant and loads back from the edge
• ✓ A trench-rescue plan that does not put a second worker at risk

The SWMS for this work

This category has a dedicated guide and generator: Excavation SWMS. It covers the specific hazards and controls above and produces a site-specific document in minutes.

Trades that do this work

These trades commonly need a SWMS for this category. Each has a trade-specific SWMS:

Excavation / Earthmoving SWMSPlumber SWMSConcreter SWMS

Other high risk construction work

with a Risk of Falling More Than 2 Metreson a Telecommunication TowerDemolition of a Load-Bearing StructureLikely to Disturb AsbestosStructural Alterations Requiring Temporary SupportIn or Near a Confined SpaceAll 18 categories