The strongest earthquake to hit Taiwan in 25 years has killed four and injured hundreds of people, damaging buildings and halting rail traffic. The quake on Wednesday off the island’s east coast, which had a magnitude of 7.2 , also forced the evacuation of semiconductor manufacturing plants. That is a reminder of how exposed the world’s chip supply is to seismic risk.

Taiwan Semiconductor Manufacturing Co, the world’s largest maker of advanced chips, stopped some chipmaking machinery and evacuated staff from facilities after the quake. Smaller local peer United Microelectronics Corp has also shut down machinery and evacuated staff at certain facilities.

Technological advancements in chip fabrication plant building in recent years have helped lower the risk of disruption and damage from earthquakes. Still, the high levels of precision required to make semiconductors means earthquakes remain a serious challenge to the industry.