Disaster Recovery - Confined spaces
As a result of a disaster, there is often the need to enter confined areas to assess damage or to make repairs. The risks of doing so may have increased due to lack of structural integrity, inflow of water and potential for toxic gas build up.
Confined spaces that have been previously assessed as hazard-free may now be dangerous with risk of collapse and entrapment, and unbreathable ‘air’.
What is a confined space?
A confined space is any area that is not intended for human occupancy, has limited access or has the potential for containing a toxic or oxygen deficient atmosphere.
Examples of confined spaces include:
- partially collapsed buildings
- enclosed foundations, basements, cellars or other underground areas
- fully enclosed storage structures e.g. grain silos, vessels or tanks
- deep man-made trenches
- collapsed ground or fissures
- open top vats (heavy toxic gas builds up in the bottom)
- damaged furnace, oven or chemical treatment rooms
Confined spaces may be more hazardous because of:
- weakening of side walls or structural integrity
- structural imbalance
- gas build up from water and sewage inflow
- fracture of chemical containment
- toxic mixing of gasses
What are the risks of confined spaces?
- entrapment from collapse of structure or side walls
- toxic gas build up
- asphyxiation (lack of oxygen)
- being engulfed by products (such as grain or sawdust)
Before considering entering, ask yourself: ”Is this a potential confined space?”
Plan:
- Is it safe to enter?
- Is any equipment needed so I can get out quickly?
- Do I need to enter this space?
- Seek advice from a building inspector or a qualified engineer before attempting to carry out any work where there is any uncertainty about keeping people safe during the operation.
- What equipment might I need?
- Air monitor
- Escape equipment
- Breathing apparatus
Structures:
- Externally assess for visible damage before entry.
- Consider if there could be structural damage that is not visible or apparent.
- Support trench sides before entering.
Atmosphere:
- Test the atmosphere. Is there enough oxygen in the air?
- Don’t rely on smell! Use air monitors to test for air contamination.
- Do I need forced ventilation or breathing apparatus?
Hazards:
- Prevent accidental introduction of hazards, e.g. steam, water, or gasses through piping, ducts or vents.
- Close off, de-energise, switch off electricity, gas or other power sources, lockout or tag-out machinery before entry.
Further information
For more information see:
- Australian/New Zealand standard AS/NZS 2865: 1995 Safe working in a confined space
- Safe working in a confined space – Department of Labour
- Confined spaces – planning entry and working safely – Department of Labour
