Evaluation of site vibrations for metrology laboratories

• Published in: Measurement science & technology 2000-10, Vol.11 (10), p.1527-1536
• Main Authors: Bessason, Bjarni, Madshus, Christian
• Format: Article
• Language: English
• Subjects: Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Laboratory procedures; Mechanical instruments, equipment and techniques; Metrology, measurements and laboratory procedures; Physics; Vibration isolation
• ISSN: 0957-0233; 1361-6501
• DOI: 10.1088/0957-0233/11/10/315

The Norwegian Metrology and Accreditation Service (Justervesenet) inaugurated a new facility in 1997 on a rock site at Kjeller, about 25 km north of Oslo. Justervesenet administers the national measurement standards, performs high-precision calibration of instruments and is responsible for accreditation of regional metrology laboratories. Vibration control is of concern in the facility. Internal vibrations are generated by human activity, mechanical systems and equipment inside the building, and there are external vibration sources outside the building. In order to estimate the vibration levels, an extensive measurement and analysis programme was carried out, including vibration monitoring at the site for 37 days; controlled measurements of vibrations from internal vibration sources; earthquake hazard analysis; and analysis of footstep-induced vibrations. Based on the results from this programme, the principal layout of the building was formulated and the following countermeasures were designed: active vibration isolation of the internal sources; constructional joints to cut wave transmission paths; and passive vibration isolation of the foundations supporting the sensitive equipment. (Original abstract - amended)