From the WHS Act Regulation 5:A confined space means an enclosed or partially enclosed space that:
- is not designed or intended primarily to be occupied by a person; and
- is, or is designed or intended to be, at normal atmospheric pressure while any person is in the space; and
- is or is likely to be a risk to health and safety from: an atmosphere that does not have a safe oxygen level, or
- contaminants, including airborne gases, vapours and dusts, that may cause injury from fire or explosion, or
- harmful concentrations of any airborne contaminants, or
- engulfment.
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 WHS Regulations.
WHAT IS NOT A CONFINED SPACE FOR THE PURPOSES OF THE WHS REGULATIONS?
A confined space does not include a mine shaft or the workings of a mine.
The following kinds of workplaces are also generally not confined spaces for the purposes of the WHS Regulations:
- places that are intended for human occupancy and have adequate ventilation, lighting and safe means of entry and exit, such as offices and workshops
- some enclosed or partially enclosed spaces that at particular times have harmful airborne contaminants but are designed for a person to occupy, for example abrasive blasting or spray painting booths
- enclosed or partially enclosed spaces that are designed to be occasionally occupied by a person if the space has a readily and conveniently accessible means of entry and exit via a doorway at ground level, for example:
a. a cool store accessed by a LPG forklift to move stock – although the use of a LPG forklift in a cool store can be hazardous, the door at ground level means that once the alarm is raised, escape and rescue can happen quickly
b. a fumigated shipping container with a large ground level opening will facilitate easy escape and rescue.
Trenches are not considered confined spaces based on the risk of structural collapse alone, but will be confined spaces if they potentially contain concentrations of airborne
contaminants that may cause impairment, loss of consciousness or asphyxiation.