Are you responsible for digging a trench or a death trap?

Are you responsible for digging a trench or a death trap? 

Not using appropriate controls when digging a trench can be fatal.

WorkSafe is warning employers and workers to take trenching safety seriously. Since 2017, there have been three fatalities due to trades digging a trench without appropriate controls at Victorian construction worksites. This highlights the significant need to address unsafe trenching practice in the construction industry. 

To reduce the risk of incidents occurring during trenching work, employers and self-employed persons need to be adequately prepared, have the right controls in place, and adhere to OHS rules and regulations. 

Use our guide to safe trenching controls in the video featured above.

Before the trenching work begins

Employers and self-employed workers should create a documented safe system of work identifying the hazards and risks. They must: 

• Where required, fill out a WorkSafe Excavation Notification and email it to WorkSafe for trenches 1.5 meters or more 
• Develop a safe work method statement (SWMS) prior to work commencing: 
  • For all trenches where the depth exceeds 1.5 metres 
  • Where powered mobile plant is involved. 

Preparation for digging a trench is of utmost importance. To ensure that trenching work is adequately prepared, employers must: 

• Regardless of the depth, have an emergency procedure in place if there is a risk of a worker becoming engulfed 
• Determine appropriate engulfment control measures 
• Ensure site can be secured. 

During the trenching work

Regardless of the depth of a trench, engulfment control measures must be in place where workers are at risk of potential engulfment. Examples of such controls are: 

• Benching or battering the walls to prevent collapse 
• Shoring systems to support the sides 
• Trench shields. 

Appropriate supervision by a competent person, experienced in trenching works should be provided focusing on factors such as: 

• Workers remaining within engulfment control measures, including where protection is being progressively installed 
• Materials, spoil and plant are kept away from the trench edge 
• The trench and work area are secure and will prevent unauthorised access 
• Any changes to the work or soil conditions. 

Fall prevention

Falls into trenches can also lead to serious or fatal injuries. Not only do you need to protect workers entering and exiting trenches, but also anyone working nearby from falling into trenches. Fall protection controls may include, but are not limited to: 

• Extending the trench shield at least 900mm above the trench 
• Fitting trench shield systems with attachable guardrail system. Where possible, be fitted before installing the trench shields 

• Appropriate fall protection in place during access/egress 
• Exclusion zones of at least 2 metres where possible, around excavation works 
• Securing the work area to prevent unauthorised access. 

More information on digging a trench safely onsite, visit worksafe.vic.gov.au/trenching for safe trenching practices.