Incident commanders should establish resilient telecommunications arrangements and carry out regular testing to confirm that contact has not been lost with crews operating in subsurface environments and infrastructure.

For incidents, particularly in older infrastructure, it may be appropriate to mobilise or request an attendance to more than one location. This will assist where:

• There is limited or no smoke ventilation or fire stopping
• There is limited or no effective communication system

The incident commander will need to consider establishing and maintaining:

• Communications with the tunnel operator
• Communications with fire control
• Using UHF radios, assign channels, and agree on call signs
• Communications with other agencies
• Communications within the subsurface environment