WHS vs OHS: What is the Difference, and Why Does Victoria Differ?

Why the Names Changed: OHS to WHS

Occupational Health and Safety (OHS) was the standard terminology for workplace safety legislation across Australia until 2009, when Safe Work Australia began developing the harmonised national framework. The harmonised model Act adopted the term Work Health and Safety (WHS) to signal a broader scope: the inclusion of psychological health alongside physical health and safety, and a shift in language from occupation-specific to work-based coverage.

In practical terms, OHS and WHS refer to the same field of law. When practitioners and experts use either term, they are generally referring to workplace health and safety law. The distinction that matters is not between the words OHS and WHS, but between the specific legislative frameworks that apply in different jurisdictions. Victoria retained the OHS Act 2004 while all other states and territories adopted the harmonised WHS Act 2011 or its equivalent.

Which States Use the WHS Act 2011

Practical Differences Between the OHS Act and WHS Act

The most significant practical differences between the OHS Act 2004 (Vic) and the harmonised WHS Act relate to the duty structures and the officer obligations.

Primary Duty of Care

Both the OHS Act and the WHS Act impose a primary duty on employers and those who manage or control workplaces. The WHS Act uses the PCBU concept, which is broader than the OHS Act's employer concept and covers a wider range of persons including those who influence and direct work. In practice, the duties reach similar persons in similar situations, but the WHS Act's PCBU framework is more flexible in capturing newer work arrangements such as labour hire and gig-economy work.

Officer Due Diligence

The WHS Act's section 27 officer due diligence duty is more detailed and more demanding than the equivalent Victorian provisions. Under the WHS Act, officers have personal obligations to acquire WHS knowledge, understand operations and hazards, ensure resources are provided and verify that systems are implemented. Victorian officer obligations are similar in intent but less explicitly defined. Officer prosecutions are common under both frameworks following serious incidents.

Offence Categories and Penalties

The WHS Act has three categories of offence with penalties up to $3 million for corporations for the most serious Category 1 offences. The OHS Act has its own penalty structure, which differs in quantum but similarly imposes significant penalties for serious failures. Penalty levels in both jurisdictions have increased significantly in recent years.

Practical Implications for Case Analysis by Jurisdiction

When instructing a WHS expert for a Victorian matter, confirm that the expert is familiar with the OHS Act 2004 framework and will conduct the analysis against Victorian legislation, not the harmonised WHS Act. Most experienced WHS experts are familiar with both frameworks, but it is worth confirming at the outset.

For matters in all other states and territories, the harmonised WHS Act applies and expert analysis is conducted against that framework, with any state-specific variations noted where relevant. Western Australia adopted the WHS Act 2020 only from March 2022, so for historical matters before that date, analysis is conducted against the OSH Act 1984 (WA).

See the WHS Act 2011 explained article for a full overview of the harmonised framework, and the Melbourne WHS expert page for detail on Victorian instructions. The duty holder obligations article addresses the PCBU framework in WHS Act jurisdictions.