Electrical Power Systems Availability in Buildings Exposed to Seismic Hazard—Part I: Electrical Criteria and Part II: Mechanical Criteria

Part I-Earthquakes cause serious problems to the reliability and continuity of the supply of electrical power systems, particularly in sensitive structures such as hospitals. The mechanical and electrical criteria for the design and installation should take building categories (based on occupancy and/or activity importance) into account. Three levels of functional performance following an earthquake are identified for equipment. A power distribution topology, which this paper refers to as the “brush-distribution system,” is discussed. Part II-After an earthquake, a building could be unusable, not necessarily due to structural damage but because electrical and mechanical systems that are not structural components have sustained damage and are inoperable. Designers of building electrical systems need to study the special requirements for the design and installation of electrical power systems in buildings that are situated in areas that where seismic events are possible. One important goal is to maintain the functionality and the integrity of the power system following an earthquake. If the layout of the electrical components is done with regard to placing the more critical components at the ground level or at other locations where the accelerations are minimized, the probability that the electrical system will continue to function after an earthquake is increased.