Confined spaces pose dangers because they are usually not designed to be areas where people work. Confined spaces often have poor ventilation, which allows hazardous atmospheres to develop quickly, especially if the space is small. The hazards are not always obvious and may change from one entry into the confined space to the next.
The risks of working in confined spaces include loss of consciousness, impairment, injury or death from:
- The immediate effects of airborne contaminants
- fire or explosion from the ignition of flammable contaminants
- difficulty rescuing and treating an injured or unconscious person
- oxygen deficiency or immersion in a free-flowing material, such as grain, sand, fertiliser, water or other liquids
- falls from a height
- environmental factors, for example, extremes in temperature
- poor lighting and
- manual handling.
Meaning of confined space
A confined space includes any enclosed or partially enclosed space that:
- is not designed or intended primarily to be occupied by a person
- is, or is designed or intended to be, at normal atmospheric pressure while a person is in space
- is, or is likely to be, a risk because of the atmosphere, contaminants or engulfment.
A confined space is determined by the hazards associated with specific circumstances and not just because work is performed in a small space.
Entry into a confined space means a person’s head or upper body is in the confined space or within the boundary of the confined space.
Confined spaces are commonly found in vats, tanks, pits, pipes, ducts, flues, chimneys, silos, containers, pressure vessels, underground sewers, wet or dry wells, shafts, trenches, tunnels or other similar enclosed or partially enclosed structures when these examples meet the definition of a confined space in the Work Health and Safety (General) Regulations 2022 [WHS Regulations].
Determining whether a space is a confined space
A confined space is determined by the structure and hazards associated with the work being carried out. For example, a space may become a confined space if work to be carried out in the space would generate harmful concentrations of airborne contaminants.
For a confined space to be classified as a non-confined space, the structure and its use needs to have undergone sufficient change in order to eliminate all the hazards that defined it as a confined space. Temporary control measures measures such as providing temporary ventilation or achieving a satisfactory pre-entry gas test will not be sufficient for a confined space to be classified as a non-confined space.
Frequently asked questions
Resources and guidance
- Confined spaces: Code of practice
- How to manage work health and safety risks: Code of practice
- Main responsibilities and duties under WHS
- Confined space: mining self-assessment
- Confined space entry: Poster
- Working in a confined space: Mine safety matters pamphlet