TOKYO GAS TOP > Corporate Information > Approach/Activity > Technical development > Earthquake disaster prevention & stable supply > Ultrahigh Density Real Time Earthquake Disaster Prevention System – SUPREME

Ultrahigh Density Real Time Earthquake Disaster Prevention System – SUPREME

The SUPREME system is a real time earthquake disaster prevention system for the prevention of secondary disasters related to gas leakage when a major earthquake occurs. The system gathers information from about 4,000 seismometer installed in various locations, and is able to interrupt gas supplies remotely when necessary.


The SUPREME system collects information promptly in an adequate manner and manages town gas supplies in order to prevent secondary disasters related to city gas.


System Overview

The SUPREME system consists of seismometers (SI sensors) installed in approximately 4,000 district gas governors that supply low-pressure gas. When these sensors detects a major earthquake that could potentially cause significant damage to gas pipes and structures, the system automatically interrupts the gas supply in order to protect the safety of the region as a whole.

Under the SUPREME system, one ultrahigh density SI sensor is installed and controlled in each of our approximately 1-km square areas. There is currently no other system like SUPREME in the world today. Tokyo Gas has split its medium-pressure and low-pressure pipeline networks into multiple blocks in order to minimize the impact of a gas outage. With this approach, pipelines in highly affected areas are separated from other areas where the damage is less, therefore minimizing the influence of gas supply interruptions. The SUPREME system is also capable of remotely interrupting the gas supply by the block.

This system supports activities aimed at preventing secondary disasters in a prompt and suitable manner by such measures as conducting damage estimations based on compiled earthquake data. When the Great East Japan Earthquake struck, the SUPREME system gathered earthquake data from approximately 4,000 locations in about five minutes. On account of this system, we were able to make prompt decisions as to whether the gas supply should be interrupted or not.

State of shaking of the Tokyo metropolitan area detected by SI
sensors(*) at the Great East Japan Earthquake
(*)  Including some information by a part of SI sensor of the peripheral
gas company
Kanto region centering around Tokyo

Tokyo Gas Co., Ltd. divides its gas supply area into about 250 blocks in order to minimize the range affected by any gas supply interruption.

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The SUPREME system is able to evaluate earthquake information gathered from about 4,000 seismometers installed in each of the district gas governors operated by Tokyo Gas. Moreover, this system is capable of utilizing data collected to estimate damage to gas pipeline networks by organizing and complementing the information on a per 50-m mesh basis. A series of this damage estimation is conducted in about a 10-minute span following the occurrence of an earthquake.


We are making the utmost effort to deepen SUPREME as an earthquake disaster prevention system through enhancements to the accuracy of damage estimations and the gathering of information necessary for activities related to early restoration.

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