This document discusses earthquake monitoring and early warning technology. It provides details on how earthquakes are measured with seismometers and describes the magnitude and intensity scales. Examples of large historical earthquakes in the US are listed. The document outlines how earthquake early warning systems work, with sensors detecting waves and alerting centers notifying people. It profiles various hardware components used in these systems, including seismic recorders, programmable automation controllers, touch screen PLCs, and SCADA software. Examples of applications like high speed railway warning systems and factory emergency controls are described.