Earthquake Measures

Tokyo Gas implements rigorous earthquake and disaster prevention measures to ensure the safety of city gas and minimize the impact of earthquake-caused foundation movement and disasters.

Earthquake Measures

Suspension and restoration of gas supply after large earthquakes

The low-pressure and medium-pressure pipeline networks of Tokyo Gas are divided into several blocks, making it possible to limit to a minimum the areas where gas supply is suspended by isolating areas with major damage.
There are approximately 4,000 district regulators (pressure regulators) in the areas which Tokyo Gas supplies and there are SI sensors (seismometers) established at each location. District regulators that detect large sways that may damage gas pipelines will automatically shut off gas supply and so the supply of gas will be suspended in units of blocks.

Pipeline blocks

Pipeline blocks

Suspension of gas supply by blocks

Suspension of gas supply by blocks

Restoration work will commence if damage has been sustained. If there is no damage, the supply will be resumed promptly.

Restoration according to the status of damage

The restoration process is
arranged according to the condition of damage.

Closing work

Workers visit all residences to close gas valves.

TG-DRESS Onsite reports of operation
Regional division

Valves are closed and gas pipes partitioned to create areas of 2,000-3,000 households.

Underground gas pipe restoration

Underground gas pipes are inspected and damaged sections are repaired.

Resumption of district regulators

District regulators (pressure regulators) where gas supply is shut off are resumed.

Opening work

Workers visit all residences to confirm that gas may be used safely.

TG-DRESS Onsite reports of operation
Restoration complete!

Gas supply is promptly resumed
at areas with no damage.

Resumption of district regulators

SUPREME extracts blocks where there is no damage from the earthquake and where pipeline pressure has not decreased after shutting off gas.

Supply is promptly resumed at district regulators where remote resumption is possible without the need to dispatch workers.

Restoration complete!

The status of supply and of restoration by region may be checked on the Gas Service Restoration Map

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