glossary Glossary 4 min read

Due diligence (WHS officer duty)

Due diligence under WHS Act s.27 is the standard officers must meet to ensure their PCBU complies. Six steps from knowledge to verification. The officer prosecution test.

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Due diligence in the WHS context is the statutory standard an officer of a PCBU must meet under section 27 of the model Work Health and Safety Act to ensure the PCBU complies with its WHS duties. It is both the duty itself (what an officer must do) and the defence in any officer-level prosecution (what an officer can point to if charged). Verified 2026-05-16.

For a residential builder running as a Pty Ltd company, the company directors and officers carry the section 27 due diligence duty. The company itself is the PCBU; the directors are the officers.

The six steps of due diligence under WHS Act s.27:

#StepWhat an officer actually does
1Acquire and keep up-to-date knowledge of WHS mattersStay current on WHS Act amendments, industry hazards, codes of practice
2Gain understanding of the nature of the PCBU’s operations and hazardsWalk site, talk to crew, know what the actual hazards are
3Ensure the PCBU has available and uses appropriate resourcesBudget for PPE, training, plant maintenance
4Ensure the PCBU has appropriate processes for receiving and considering information about incidents, hazards, and risksIncident reporting system, toolbox talks, near-miss capture
5Ensure the PCBU has processes for complying with its WHS dutiesSafe Work Method Statements (SWMS), site inductions, regulator compliance
6Verify that the processes and resources are being used (audit)Site walks, internal audits, take-up checks

The list is conjunctive: an officer must do all six, not pick and choose.

Why this matters for builders:

  • Officer-level prosecution: WHS regulators can charge directors personally under WHS Act s.27 if an incident occurred and the officer cannot demonstrate due diligence. The penalties at officer-level are separate from and in addition to any PCBU-level penalty under Category 1, 2 or 3 offences.
  • Personal liability: officer-level prosecution carries personal financial liability (capped, but substantial) and can include imprisonment for Category 1 offences.
  • Insurance: management liability policies typically cover officer-level WHS prosecution defence costs but not the underlying fine (statutory penalties are uninsurable in Australia).

What “ensuring the PCBU has processes” looks like at site level:

  • Site induction records for every worker (sub-contractor or employee).
  • SWMS for every high-risk activity, kept on site.
  • Toolbox talks recorded with sign-off sheets.
  • Plant pre-start checks documented.
  • Incident register maintained.
  • Subcontractor agreement that the subbie’s PCBU duties flow through to their workers.

Common officer-level defence failures:

  • “I didn’t know about the hazard”: s.27 requires acquiring knowledge. Ignorance is not a defence.
  • “I left it to the site supervisor”: delegation is permitted, but the officer must verify the supervisor has the resources and processes. Unverified delegation is not due diligence.
  • “We had a SWMS but no one followed it”: process exists but step 6 (verify) is missing. Common failure mode.

Also known as: WHS officer duty; section 27 duty; officer due-diligence.

Category: WHS.

See also


Last updated: 2026-05-16. Verified: 2026-05-16. Quarterly review for currency.