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Control measure

Isolate or limit gases, liquids and other flowing materials

Control measure knowledge

When operating in a confined space, the ingress of gas, liquids or flowing materials will affect the environment, which may become hazardous to those inside the confined space.

Personnel must be aware of the environment and any associated processes that may affect the confined space and take all appropriate actions to prevent the ingress of substances.

The removal of materials, such as sludge, may reduce the quantity of toxic or asphyxiate gases being released into the confined space. However, this activity should be subject to a risk assessment as it may release more gases.

Strategic actions

Fire and rescue services should:
  • Capture information about the storage or use of gases, liquids or flowing materials in Site-Specific Risk Information (SSRI)

Tactical actions

Incident commanders should:
  • Refer to information provided by SSRI site working plan or the responsible person, about the storage or use of gases, liquids or flowing materials in confined spaces

  • Investigate the possibility of ingress from gas, liquids or flowing materials into the confined space, including surface water 

  • Isolate the confined space or sources to prevent the ingress of gas, liquids or flowing materials

  • Identify the presence of materials, such as sludge, that may release gases, especially if disturbed

  • Consider the controlled removal of materials, to reduce the quantity of gases being released