Did ISO 45001 replace AS/NZS 4801 and OHSAS 18001?

Yes. ISO 45001 is the modern international safety management standard that superseded OHSAS 18001 and the older Australian/New Zealand standard AS/NZS 4801. Organisations previously certified to those standards have transitioned to ISO 45001, and new certifications are to ISO 45001.

Is ISO 45001 worth it for a small business?

For many SMEs the driver is winning work — head contractors, government and larger clients increasingly require ISO 45001 or safety prequalification. Beyond that, a proper safety management system reduces incidents and the costs that come with them. It's worth it when it opens work and genuinely lowers your risk.

Guide · Safety

ISO 45001 explained

Q: What is ISO 45001?

ISO 45001 is the international standard for an occupational health and safety (OH&S) management system. It gives organisations a framework to manage safety risks, prevent injury and ill health, and continually improve — and it can be independently certified. It shares its structure with ISO 9001 and 14001, so it integrates easily.

ISO 45001 is the international standard for managing work health and safety — and increasingly the ticket to working for head contractors, government and large clients across Australia and New Zealand. Here's what it is, what it requires, how it replaced the old AS/NZS 4801, and whether it's worth it for a small business.

What ISO 45001 is

ISO 45001 sets out the requirements for an occupational health and safety (OH&S) management system: a structured way to manage safety risks, prevent injury and ill health, meet your legal duties, and continually improve. Like ISO 9001 (quality) and ISO 14001 (environment), it's built on the common Annex SL structure — which is why the three integrate so neatly into a single system. And like them, it can be independently certified by an accredited certification body.

How it replaced AS/NZS 4801 and OHSAS 18001

Before ISO 45001, safety management was certified against OHSAS 18001 internationally and AS/NZS 4801 in Australia and New Zealand. ISO 45001 (published 2018) superseded both. Organisations that held those older certifications transitioned to ISO 45001, and new certification is to ISO 45001. If a tender still references AS/NZS 4801, it's dated — ISO 45001 is the current standard.

What ISO 45001 requires

Leadership and worker participation — top management ownership, and genuine consultation with workers.
Hazard identification and risk assessment — systematically finding and controlling OH&S risks.
Legal and other requirements — knowing and meeting your compliance obligations.
Objectives and planning — measurable safety objectives and plans to reach them.
Support and operation — competence, communication, documented information, operational controls and emergency preparedness.
Performance evaluation — monitoring, incident investigation, internal audit and management review.
Improvement — corrective action and continual improvement.

None of this replaces your WHS legal duties — it's the system that helps you meet them consistently and prove it.

ISO 45001, built around your work

BigTick generates a complete ISO 45001 safety management system tailored to your business — hazard and risk registers, safe work procedures, training matrix, incident reporting, emergency plans, audits and reviews — and runs it on every phone. Add ISO 9001 and 14001 to the same integrated system whenever you're ready.

Is it worth it for a small business?

For most SMEs the trigger is commercial: increasingly, you can't get on site or win the tender without ISO 45001 certification or a recognised safety prequalification. Beyond that, a real safety management system reduces incidents — and incidents are expensive, in lost time, claims and reputation. It's worth it when it opens work and genuinely lowers your risk, which for anyone doing physical or field work, it does.

ISO 45001 and prequalification

In Australia and New Zealand, ISO 45001 often sits alongside contractor safety prequalification schemes — Cm3, Avetta and ISNetworld in Australia, and SiteWise and the Totika-recognised schemes in New Zealand. A solid ISO 45001 system makes those prequalifications far easier, because the evidence they ask for is exactly what the standard makes you keep.

Get ISO 45001 without the consultant

Start a free trial and watch BigTick build your ISO 45001 safety management system around your business — audit-ready, and on every phone in your team.

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Frequently asked questions

What is ISO 45001?

The international standard for an occupational health and safety management system. It provides a framework to manage safety risks, prevent injury and ill health, and continually improve — and it can be independently certified. It shares its structure with ISO 9001 and 14001.

Did it replace AS/NZS 4801 and OHSAS 18001?

Yes. ISO 45001 superseded OHSAS 18001 and the older Australian/New Zealand standard AS/NZS 4801. Existing certifications transitioned to ISO 45001, and new certification is to ISO 45001.

Is it worth it for a small business?

For many SMEs the driver is winning work — head contractors, government and larger clients increasingly require ISO 45001 or safety prequalification. Beyond that, a proper safety system reduces incidents and their costs.

Related guides

General information about ISO 45001, not legal or certification advice.