Seismic code limit states design philosophy. In February 2004 a new set of seismic codes was issued. In Spain the seismic code is called the "Norma de Construcción Sismorresistente". (See the ) In the United States the Federal Emergency Management Agency (FEMA) publishes "Recommended Seismic Provisions for New Buildings and Other Structures". Seismic code Seismic codes or earthquake codes are building codes designed to protect property and life in buildings in case of earthquakes. The need for such codes is reflected in the saying, "Earthquakes don't kill people—buildings do." Or in expanded version, “Earthquakes do not injure or kill people. Poorly built
Seismic source Seismic source A seismic source is a device that generates controlled seismic energy used to perform both reflection and refraction seismic surveys. A seismic source can be simple, such as dynamite, or it can use more sophisticated technology, such as a specialized air gun. Seismic sources can provide single pulses or continuous sweeps of energy, generating seismic waves, which travel through a medium such as water or layers of rocks. Some of the waves then reflect and refract and are recorded by receivers, such as geophones or hydrophones. Seismic sources may be used to investigate shallow subsoil structure, for engineering