Cordon control: Cylinders and pressurised gas

Control Measure Knowledge

This control measure should be read in conjunction with Cordon controls: Hazardous materials


Personnel may encounter cylinders and pressurised gases during incidents where their involvement is not expected. It is vital that they recognise them quickly when firefighting.

Initial cordon/hazard areas

Responders inside the initial cordon should use shielding and don appropriate personal protective equipment (PPE). For example, responders likely to be affected by a fireball or blast should wear breathing apparatus (BA) and full structural firefighting kit. See Personal Protective Equipment: Hazardous materials for more information.

The following key questions will assist incident commanders in assessing the immediate risk:

  • Are there cylinders at the incident?
  • Are the cylinders involved in fire? (i.e. is there direct flame contact, fire damage or radiated heat damage from the fire)
  • Are any cylinders leaking, venting, bulging or steaming?
  • What gases are involved?
  • How many cylinders are there and what size are they?
  • What is the temperature of the cylinder(s)?
  • Is any shielding provided by any buildings or structures?
  • What type of adjacent structures are there and what is their extent?
  • What is the local topography (e.g. protection provided by slopes and gradients of ground levels etc?)
  • What would be the effect of:
    • A potential blast pressure wave
    • A fireball (can travel up to 25 metres)
    • Projectiles (a cylinder may be thrown up to 150 metres* and cylinder fragments and other projectiles such as the valve assembly may be thrown up to 200 metres*)
    • Flying glass and other structural material?
  • What structural damage could be caused to buildings in the vicinity?
  • Is there a need for an exclusion zone within the hazard area?
  • Are other hazards inside or close to the initial cordon?
  • How close are surrounding buildings and infrastructure?
  • Are any buildings or infrastructure occupied or in use?

As an illustration, a 40kg 1000L cylinder travel up to 150m and create a fireball that can travel up to 25m, assuming it is not within a structure or building that would provide substantial shielding.

If cylinders, including acetylene, have not been heated then they do not represent a hazard and should be handed over to the site operator. In a developing fire situation, consider carefully moving them if there is a risk that the fire will spread and involve them.

Where members of the public are within the identified hazard area, the incident commander may wish to consider evacuation. Where this is not possible or appropriate, attempts should be made to warn of the risks and give advice to stay away from windows and doors and stay in rooms furthest away from the risk.

For further information regarding evacuation refer to National Operational Guidance: Operations Evacuations and shelter.

Strategic Actions

Tactical Actions