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Compliance Guide

Chain of Responsibility: What PCBUs Must Know About Subcontractor Safety

✍️ BlueSafe Technical Team📅 28 Nov 2025

Quick answer: Under Australian WHS law, you cannot contract out your safety obligations. As the PCBU engaging a subcontractor, you are responsible for ensuring they work safely so far as is reasonably practicable — even if they are self-employed. Failing to do so exposes you to prosecution.

Last reviewed: March 2026 by the BlueSafe Technical Team. Reflects current Model WHS Regulations.

A common myth in the construction and trade industries is: "I hired a subbie, so safety is their problem."

This is incorrect. Under Australian WHS laws, the Chain of Responsibility means that you cannot contract out your safety obligations. If you engage a subcontractor, you have a duty of care to ensure they are working safely. If they have an accident on your site, you can be held liable.

You Are the PCBU

As the entity engaging the subcontractor, you are a PCBU (Person Conducting a Business or Undertaking). The subcontractor is considered a "worker" under your influence. Therefore, you must ensure their safety so far as is reasonably practicable.

What You Must Do Before They Start

To protect your business and ensure compliance, you must have a robust Contractor Management System. Before a subbie steps foot on your site, you should collect and verify the following:

1. Insurances

Ensure they have current:

  • Workers Compensation Insurance (for their employees).
  • Public Liability Insurance.
  • Professional Indemnity (if applicable).

2. Safe Work Method Statements (SWMS)

If they are performing High Risk Construction Work, you must collect their SWMS.

  • Review it: Don't just file it. Check that it is relevant to the specific site and task.
  • Monitor it: Ensure they are actually following the controls listed in the SWMS while working.

3. Licences and Competencies

Verify they hold the necessary licences for the work (e.g., Electrical Licence, High Risk Work Licence for forklifts/cranes, White Cards).

Monitoring and Supervision

Your duty doesn't end with collecting paperwork. You must monitor the subcontractor's work.

  • Are they wearing the required PPE?
  • Are they using safe equipment?
  • Are they following the site rules?

If you see a subcontractor working unsafely, you have the authority—and the obligation—to stop the work until the issue is rectified.

The "Shared Duty" Concept

WHS laws recognise that multiple PCBUs can have a duty in relation to the same matter.

  • The Principal Contractor has a duty.
  • The Subcontractor (company) has a duty.
  • The Self-Employed Subbie has a duty.

These duties overlap. You must consult, cooperate, and coordinate with each other. You cannot assume someone else is taking care of it.

State and Territory Variations

The information on this page is based on the Model WHS Regulations published by Safe Work Australia, which have been adopted (with minor variations) by most states and territories.

JurisdictionWHS regulatorKey notes
NSWSafeWork NSWAdopted Model WHS Regulations
VICWorkSafe VictoriaUses OHS Act 2004 — some terminology differs
QLDWorkplace Health and Safety QueenslandAdopted Model WHS Regulations
SASafeWork SAAdopted Model WHS Regulations
WAWorkSafe Western AustraliaAdopted Model WHS Regulations (2022)
TASWorkSafe TasmaniaAdopted Model WHS Regulations
ACTWorkSafe ACTAdopted Model WHS Regulations
NTNT WorkSafeAdopted Model WHS Regulations

Always verify requirements with your state regulator, as local codes of practice and guidance may impose additional obligations.

Frequently asked questions

Am I responsible for a subcontractor's safety?

Yes. Hiring a subcontractor does not transfer your safety duty. As the PCBU, you must ensure their safety so far as is reasonably practicable — this includes self-employed subbies working under your direction.

What documents must I collect from subcontractors before work starts?

Before they start, collect Workers Compensation Insurance, Public Liability Insurance, relevant licences and White Cards, and a SWMS for any High Risk Construction Work they will perform.

What is the Chain of Responsibility under WHS law?

The Chain of Responsibility recognises that multiple PCBUs can share a duty over the same work. Each party must consult, cooperate, and coordinate — you cannot assume someone else is managing safety.

What happens if a subcontractor has an accident on my site?

If you have not met your duty of care — for example, by failing to collect a SWMS or monitor the work — you may be prosecuted as the engaging PCBU. Penalties under the WHS Act can reach hundreds of thousands of dollars.

Streamline Contractor Management

Managing subcontractors involves a lot of documentation. A structured WHS Management System provides the checklists, registers, and procedures you need to onboard and monitor contractors efficiently, ensuring the Chain of Responsibility remains unbroken.

Need help managing subcontractors? Explore WHS management systems.

Need Help with Compliance?

Get the templates mentioned in this guide to ensure you meet your obligations.

Still have questions?

Our team of WHS experts is here to help.