OHS Management System – Is It Different From WHS?

OHS stands for Occupational Health and Safety. It was the primary term used across Australian jurisdictions before the national harmonisation of workplace safety laws. Under OHS legislation, the focus was on protecting workers within defined occupational settings — employees engaged directly in work activities.

Each state and territory had its own OHS Act, leading to significant inconsistencies. A business operating across multiple jurisdictions could face different legal obligations, definitions, and enforcement approaches depending on location. This fragmentation was one of the key drivers behind the push for harmonised national legislation.

In 2011, the Australian Government introduced the model Work Health and Safety Act as part of a national harmonisation process. Most jurisdictions adopted this model legislation, replacing their existing OHS Acts with WHS Acts.

The shift from "Occupational Health and Safety" to "Work Health and Safety" was deliberate and substantive. The new WHS framework broadened the scope of protection beyond traditional employees to include:

• Workers of all types — employees, contractors, subcontractors, labour hire workers
• Volunteers and work experience students
• Visitors to workplaces
• Any person who may be affected by work activities

Under the WHS model, a Person Conducting a Business or Undertaking (PCBU) owes a primary duty of care to all of these groups — not just employees. This expanded duty is one of the most important distinctions between the former OHS framework and the current WHS framework.

The harmonisation also introduced consistent definitions, a uniform penalty framework, and aligned Regulations and Codes of Practice across adopting jurisdictions. The intent was to create a nationally consistent standard that reduced complexity for businesses operating across state borders.

In practical terms, an OHS Management System and a WHS Management System are functionally the same structured framework. Both are designed to:

• Identify and manage workplace health and safety risks
• Establish policies, procedures, and registers to support compliance
• Document how an organisation meets its duty of care obligations
• Provide a framework for consultation, incident management, and continuous improvement
• Support audit and certification against recognised standards such as ISO 45001

The difference is primarily one of terminology and legislative context. In harmonised jurisdictions, the system is described as a WHS Management System because it operates under WHS legislation. In Victoria, the same type of system may be described as an OHS Management System. The structure, purpose, and core documents are the same.

Adding to the terminology overlap, the international standard for safety management systems — AS/NZS ISO 45001:2018 — is formally titled Occupational Health and Safety Management Systems — Requirements with Guidance for Use. The standard uses OHS terminology throughout, reflecting international convention.

This means that even in jurisdictions where WHS is the legislative term, businesses seeking ISO 45001 certification will encounter OHS language in the standard itself. In practice, this creates no conflict — the standard is designed to be applied within any jurisdiction's legislative framework, and Australian certification bodies assess compliance against both ISO 45001 and the relevant WHS or OHS legislation.

The use of "OHS" in ISO 45001 is one of the main reasons the term remains widely used in Australia and internationally, even where WHS is the legally correct term.