Tokyo Gas is taking measures against earthquakes and other disasters to ensure that customers can always use gas safely and conveniently, 24 hours a day and 365 days a year. These measures fall under three main categories: preventive measures, emergency measures, and recovery measures. Should a disaster strike, we will strive to minimize the impact on our customers.
In preparation for a major earthquake, Tokyo Gas has established an earthquake disaster prevention system that is able to stop the supply of gas to residences and commercial buildings using their gas meters, and to entire regions through remote operation. The pipeline network is also divided into small "disaster prevention blocks" to minimize the inconvenience caused by the suspension of gas service in one or more individual blocks.
■Systems to shut off gas supply to residences and commercial buildings
In the event of a gas leak or an earthquake with a seismic intensity of 5 or more, the home gas meter's safety device activates automatically to immediately shut off the gas supply. Gas valves and appliances around the home also have their own safety devices for double- and triple-layer safety.
In the case of underground malls and high-rise buildings, the gas supply to an entire facility can be halted remotely by activating an emergency shut-off valve from the facility's disaster prevention center or administrator's office.
■Systems to shut off gas supply to an entire region that has suffered significant damage
Seismographs have been installed in all district pressure regulators (pressure regulators that convert gas from medium to low pressure) at approximately 4,000 locations throughout our service area. If the sensors detect a major earthquake, each district pressure regulator can automatically shut off the gas supply to the area that it serves, and gas supplies can also be shut off by remote control. Our service area contains the highest concentration of seismographs in the world—one for approximately every 1.0 km2—allowing us to efficiently monitor the safety of the entire area.
Tokyo Gas will work to resume service as quickly as possible in order to reduce the inconvenience experienced in areas where gas supplies have been stopped. We will make full use of our equipment and systems, which are always maintained and at the ready on a daily basis, and will work together with gas utilities nationwide to restore gas supplies as quickly as possible.
In order to restore service to undamaged districts the same day that an earthquake occurs, we began rolling out a "district pressure regulator remote restart system" in fiscal 2014, and are working to extend the system to our entire service area.
Based on the lessons drawn from disaster relief support activities conducted in the wake of the Great Hanshin-Awaji Earthquake and the Niigata Chuetsu Offshore Earthquake, Tokyo Gas has been readying mobile gas generation equipment (large PA-13A) at different locations to provide relief support when gas supplies stop. This gas generation equipment can be used to supply facilities (kitchens, etc.) until normal gas service resumes, and will be provided to customers of high-priority to society such as hospitals. Mobile gas generation equipment was actually used in the aftermath of the Great East Japan Earthquake.
Following on from fiscal 2016, we will redouble our efforts in fiscal 2017 to develop support measures, improve and enhance the information we have available on socially high-priority customers, and provide education and training in relief support utilizing the actual equipment to be used in times of disaster.
Mobile gas generation equipment
To assist large-scale restoration activities, a system of cooperation has been developed for gas utilities nationwide to work with the Japan Gas Association to provide personnel and equipment toward restoration activities. In the wake of the Great East Japan Earthquake, Tokyo Gas Group resumed service to some 30,000 of its customers within about one week, and continued to provide support personnel for two months to six gas utilities (up to a maximum of 1,950 personnel in one day). The entire group worked together to repair pipes and restore gas service so that customers could have access to gas again as soon as possible.
Damage caused in the Saibu Gas Co., Ltd. service area by the 2016 Kumamoto Earthquakes, the main shock of which struck during the early hours of April 16, 2016, led the Japan Gas Association to issue a request for assistance from city gas companies across Japan. Together these companies formed the "Service Restoration Task Force." Tokyo Gas took part, and contributed some 1,300 personnel, more than it has ever sent on such a mission before. Thanks to these combined efforts, gas service was restored to all customers in the affected areas by April 30.
In order to cut off gas supplies to prevent secondary disasters while also continuing to provide safe gas supplies to areas where damage is limited, Tokyo Gas reviews all of its business operations, which number more than 600, and ranks them in order of priority during a disaster.
If the gas supply to an area is interrupted, we will make every effort to restore service immediately, including assigning the personnel normally responsible for operations that have been interrupted to recovery work until those operations have been restored.
■Establishment of backup centers
Our systems are housed in a data center that meets high seismic standards, and we have also established a backup center in case of a major disaster. The backup center houses backup equipment and data (especially customer information and systems required to ensure safety in an emergency) so as to enable swift restoration of services after a disaster. Regular emergency drills are held, and redundancy is built into the power supply and communication systems in order to minimize the impact on customers should an emergency arise.
■Comprehensive disaster prevention training
We have conducted comprehensive disaster prevention trainings since 1983 to improve employees’ and organizations’ disaster resilience. As the fiscal 2017 comprehensive disaster prevention training was the first since full liberalization of the gas retail market, one of its objectives was to confirm that Tokyo Gas Group and the new gas retailers understand their roles and know how to work together in the event of a major disaster so as to ensure that disaster response remains as solid as ever.
Approximately 21,000 Group employees (including employees at Tokyo Gas’s subsidiaries and partner companies) took part in the training, which consisted of an initial response stage and a recovery stage. Teams from the Emergency Response Organization responded in accordance with guidelines without being informed in advance what the training scenario would be.
Headquarters during comprehensive disaster prevention training
■Disaster recovery systems
We have put in place a system for comprehensively monitoring in real time the state of disaster recovery activities. This allows all employees to share accurate information, thereby enabling swift and appropriate action to be taken. Earthquake data aggregated by SUPREME is sent to employees' mobile phones just minutes after an earthquake, and the system can also be used to confirm employees' safety and call them in to the office. Our earthquake data is also used by local authorities and government agencies.