Quick answer
Under Australian work health and safety law, a confined space is an enclosed or partially enclosed space that isn’t designed to be occupied by people, has restricted entry or exit, and is — or could be — a risk to health and safety from things like a harmful atmosphere, lack of oxygen, engulfment, or contaminants. It’s defined by those risk characteristics, not just by being small or enclosed.
The legal definition (plain English)
A space generally counts as a confined space if it ticks these boxes: it’s enclosed or partially enclosed, it’s not intended as a normal workplace for people, its entry/exit is restricted, and it has a foreseeable risk such as an unsafe oxygen level, airborne contaminants, or the chance of engulfment. Importantly, a space that looks open can still be “confined” if the atmosphere is the hazard.
Common examples
- Storage tanks, vessels and silos
- Pits, sumps, trenches and shafts
- Pipes, ducts, sewers and drains
- Tankers and shipping containers
- Boilers, pressure vessels and some plant interiors
Why confined spaces are dangerous
The big risks are atmospheric: too little oxygen, too much of a harmful gas, or flammable vapours — often with no warning signs. Add restricted exit and the difficulty of rescue, and a minor problem can become fatal quickly. That’s why entry is tightly controlled with permits, atmospheric testing, and trained standby people.
What training do you need?
Anyone entering or working in a confined space should hold nationally recognised training — RIIWHS202E Enter and Work in Confined Spaces. It covers identifying confined spaces, atmospheric testing, permits, controls, and safe entry and exit. See the Confined Space course →
Frequently asked questions
Is a confined space just any small space?
No. It’s defined by risk — enclosed, not designed for people, restricted entry/exit, and a foreseeable hazard like a harmful atmosphere. A large tank can be a confined space; a small cupboard usually isn’t.
Who decides if a space is “confined”?
The business (PCBU) must assess its spaces against the definition and manage the risks accordingly, with competent, trained workers.
What qualification covers confined space entry?
RIIWHS202E Enter and Work in Confined Spaces — nationally recognised training.
Get confined space trained
FMS Training (RTO 45189) delivers RIIWHS202E Enter and Work in Confined Spaces. Explore the course →
Last updated June 2026 · FMS Training, RTO 45189