Aesismatic device for gas

In an attempt to improve precautions against seismic risk, with regard to identification of areas of seismic activity and the technical standards for building in those areas, on march 20th 2003 the government passed a decree (no 3274) ordering that a number of guidelines, documented in the decree and developed by experts in the field, should be adopted. The decree details reclassification of areas at seismic risk with in the whole national territory. Technical document no 2 describes the calculation of stress and resistance tests for the structural elements of every type of building structure (reinforced concrete, steel, concrete...) Paragraph 4.10 (general planning criteria) focuses its attention on distribution systems with the following ruling for gas systems: ..."gas systems consuming more than 50m3/h should be provided with automatic safety shut-off valves for use in the event of an earthquake." it is a fact that damage caused by the seismic shock of an earthquake is almost always accompanied by fire and explosion, due to gas escaping from fractured pipelines. Sisma californian series safety valves are designed and manufactured in accordance with the strict united states aseismatic standards asce 25-97 and totally meet the requirements of italian law. The sisma safety valve comprises a shut-off valve with swing disc, which comes into action following vibrations.