Once you have your plan setup, do NOT deviate from it unless a real emergency occurs.

一旦确定计划，不要偏离，除非真发生紧急情况。

youdao

Since the primary waves travel more quickly than the comparatively sluggish secondary waves, the system picks up on the magnitude and speed at which the quake is approaching, and beams the data over fiber optic networks to emergency relay stations setup in corporate towers, governmental buildings, hospitals, and transportation venues such as railways.

ENGADGET: Japan Meteorological Agency develops earthquake warning system