An effective communication system must be in place and should enable communication between:
- All personnel working inside the confined space
- Personnel inside the confined space and those outside
An effective communication system should be in place to enable further resources to be requested in case of emergency. The equipment used for communication should take account of the other equipment, personal protective equipment (PPE) and respiratory protective equipment (RPE) that is used when working in confined spaces. Where there is a risk of flammable or potentially explosive atmospheres, all communication equipment that may be used in a confined space must also be protected so that it does not present a source of ignition.
Alternatives to normal communications should be considered, including dedicated urban search and rescue (USAR) capability and existing on-site systems (if functional). A leaky feeder system and deploy repeaters should be requested, if available.