ASCO Seismic White Paper 1103

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  A White Paper from the Experts in Business-Critical Continuity  TM . Seismic Certification and the Consulting Engineer  By Bhavesh Patel   Seismic Certification and the Consulting Engineer 4 Critical Factors: ã Minimizing Liabilityã Good Specificationsã Quality Assurance ã Certified Equipment Building code standards for seismic certification re-quire that critical mechani-cal, electrical and plumbing equipment must endure higher ground accelera-tion levels, or risk being red tagged during inspection, or worse. They also are be-ing more broadly applied than before.International Build-ing Code (IBC) editions since 2000 1  demand that critical equipment, such as on-site power systems that power life safety and critical branches, may need to withstand higher ground acceleration levels 2  throughout the country, including those generated by the San Andreas Fault in California. An important element in designing power systems to resist seismic events is seismic demand spectrum. It stands for short period spectral acceleration and is designated in the code as SDS. It represents the base acceleration forces for a specific site, which can range from 0 to 2.46. Equipment must be certi-fied to the SDS values for both the site at which it will be installed and the loca-tion in the building where it will operate. 1. IBC 2000 refers to ASCE 7-98, 2003 refers to ASCE 7-02, and 2006 and 2009 refers to ASCE 7-05 as the performance bench-marks for seismic criteria. 2. The U.S. Geological Survey as-signs ground acceleration levels. U.S. Geological Survey Peak Ground Acceleration map of the continental United States showing a two per-cent in 50 year probability of exceedance.  For example, power sys-tems installed on rooftops in California must be certi-fied for rooftop applica-tions at the SDS value for the project. In California’s case, the value is 1.93. Bottom line, engine-gen-erators and their support equipment, switchgear and power transfer switch-es must be able to oper-ate after a severe seismic event.The IBC Code require-ments for special seismic certification of electrical equipment can be game changers for consulting en-gineers. The requirements raise the bar to the level of “proof” that design, construction and equip-ment specification, instal-lation and operation will enable essential facilities to continue their intended function after severe seismic events. “Proof” is actual shake table testing of a system and its compo-nents, rather than solely an engineering analysis.Special inspectors, not building code officials, evaluate facilities for com-pliance. If a facility does not comply, the inspector has a legal right to with-draw the certificate of oc-cupancy even though the building may be occupied. The insurance company could declare the building uninsurable and put the consulting engineer in the cross hairs. Consulting engineers need to address four critical issues to ensure their proj-ects meet code and they protect themselves. They need to:1. Minimize their exposure to risk and liability by fa-miliarizing themselves with evolving seismic code standards, 2. Develop well-written specifications that account for ground acceleration and other seismic data for a site, 3. Work with contractors on a quality assurance program, and 4. Specify equipment properly certified for the specific building location. Consulting engineers need to address four critical issues to ensure their projects meet code and that they protect themselves. Real-Life Risk On-site power equipment that is essential to build-ing operation and that is specified and installed in critical facilities but does not comply with IBC stan-dards in jurisdictions that have adopted the code risk being red tagged. Already, engine-generator equip-ment installed in a new construction hospital in St. Louis, Mo. was red tagged for not being seismically qualified. For a critical facility, such as a hospital, the ability of transfer switch mechanisms to function even during  a seismic event could literally be life saving.  St. Louis is near the New Madrid fault area, which has generated the most severe ground acceleration during a seismic event in the U.S. Ground accelera-tion during a seismic event is a major determinant of destruction. The seismic standards of IBC refer to higher ground acceleration levels specified in ASCE 7-05, based on the New Madrid events of 1811 and 1812. What that meant to the hospital project is that the engine-generator manu-facturer had to send a retrofit kit to the site that was field installed to bring the equipment into com-pliance. It could have been worse—for the hospital as well as others involved in the project. Non-compliant equipment could boost a building owner’s insurance premi-um. If the equipment fails to operate after a seismic event, it could result in physical damage and per-haps loss of life. Insurance claims could be, and have been, denied. Even if equipment operates properly after a seismic event, liability still may arise for the consulting engineer. One example could occur if the emer-gency power design didn’t include all of a hospital’s chillers. After normal source power failed after a seismic event, ambient temperature and relative humidity might rise to lev-els that could compromise patients on life support or the ability of operating rooms to function com-fortably. The consulting engineer, hospital owner and others could be liable. Richard Berger, chair-man of The VMC Group, a company specializing in shock, vibration, seismic and noise control and the largest certifying agency for the power generation market said, “It could be a legal issue to be tried in court.”An air handling unit at an office building in Hous-ton, for example, did not withstand wind speeds that were included in the building’s design criteria. After Hurricane Ike hit the area in 2008, the unit dislodged from the build-ing allowing water to enter ductwork and cause ex-tensive interior damage to the building. The insurance company denied the build-ing owner’s claim because the unit had not complied with building codes. It’s Not Just Building Owners at Risk Besides building owners, risk and liability also lie with contractors, consult-ing engineers, project en-gineers and critical equip-ment manufacturers. The building owner and other plaintiffs could sue them for improperly designed and installed systems. As of May 2010, for example, Berger of The VMC Group said 38 lawsuits have been filed as a result of the code. Engineering professionals can minimize their expo-sure by ensuring critical equipment is specified and installed according to cur-rent code standards. It seems simple enough, but it isn’t always. Too many professionals may believe they are protected by the master specifica-tion. But if it isn’t written New Madrid Seismic Zone and vicinity. Seismic events in the zone have caused damage to structures in Ohio. U.S. Geological Survey image
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