核电站选址要求保证地震危险性只是总危险性的微小部分。核电站享有比火力或水力发电站更显著的安全记录,这是由于在选址过程中极端谨慎。对于这一优良的工作性能,还有一个原因,可能是大的地球物理事件极端罕见。虽然有许多核电站运转在地震活动区或是容易遭受地球物理灾害,但还没有发生过由地震、火山喷发或海啸引起的事故。而且也确实没有核电站遭受过接近于其设计的地震荷载。人为事故以及由于磨损和疲劳造成的仪器 The site location of a nuclear power plant to ensure seismic risk is only a tiny fraction of the total risk. Nuclear power plants enjoy a more significant safety record than thermal or hydropower plants because of extreme caution in the process of site selection. Another reason for this excellent performance may be that extreme geophysical events are extremely rare. Although many nuclear power plants operate in the seismic zone or are vulnerable to geophysical hazards, no accident caused by an earthquake, a volcano or a tsunami has occurred. And indeed, no nuclear power station has suffered seismic loads close to its design. Accidents and equipment caused by wear and fatigue