Toward Halving Damage from a Tokyo Metropolitan Earthquake: Government Revises 'Basic Plan for Promoting Emergency Measures'

Explanation

In preparation for a 'Tokyo metropolitan earthquake,' said to have roughly a 70% chance of occurring within the next 30 years, the government has revised its 'Basic Plan for Promoting Emergency Measures.' The plan sets a goal of halving damage over the next ten years, with the installation of 'seismic (quake-sensing) breakers' as one of its key pillars.

In a Tokyo metropolitan earthquake, damage is expected to be worsened not only by building collapses but also by fires breaking out simultaneously across multiple locations after the quake, especially in areas densely packed with wooden housing. A seismic breaker is a device that automatically cuts off electricity when it detects shaking above a certain threshold, preventing 'restoration fires' that can occur when power is restored after an outage.

Earthquakes themselves are natural phenomena caused by the rupture of rock at plate boundaries or within plates, and they cannot be stopped by human effort. However, damage such as post-quake fires and building collapse can be greatly reduced through advance preparation. The concept of 'disaster mitigation'—not eliminating disasters entirely but minimizing the damage they cause—has become central to modern disaster prevention.