TOKYO GAS TOP > Technical development > Earthquake disaster prevention & stable supply > Emergency Communication Host System (ECHO)

Emergency Communication Host System (ECHO)

This is a system to conduct simultaneous announcement from the service command center to gas safety offices by sound broadcasting and facsimile in an emergency situation.



  • Transmission of communications and instructions to district offices in the event of a quake
  • Hotlines for when the internal phone network is down



Diagram of the composition of ECHO

ECHO connects voice broadcasting, safety communications telephone, and IP fax systems to a highly dependable private wireless communications network, allowing uninterrupted communications even when lines provided by carriers go down in the event of an earthquake or other emergency.
The system is disaster hardened by situating its core servers in a redundant configuration at the service command center (head office) and a sub-center, so the system can be run from the sub-center even if head office is damaged.



  • Voice broadcasting system The system is equipped with text-to-speech functionality to lighten the load on emergency broadcast personnel, allowing clear transmissions to all destinations even in emergencies.
  • Safety communications telephone and IP fax systems As district offices are connected via a wireless communications network, hotlines still function even when internal phone lines are down. This wireless communications network can also function as an IP network, which means IP faxes using the line can send and receive faxes in around a tenth of the time it takes over conventional analog phone lines.



Tokyo Gas aims to further improve usability and connectivity to other systems to make the system easier to operate in emergencies.

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