47.5 MB - The Whole Building Design Guide

and subsequent progressive failure;(3) they do not adequately addressoccupant protection with respect tomissiles; (4) they do not adequatelyaddress protection of equipment inelevator penthouses; (5) they do notaccount for interruption of water serviceor prolonged interruption of electricalpower; and (6) the current requirementsfor shelters are limited. All of theseelements are of extreme importance forcritical facilities, which need to remainoperational before, during, and after adisaster. Guidance to overcome theseshortcomings is given in Section 3.4.m The 2006 IBC does not account fortornadoes; therefore, except for weaktornadoes, it is ineffective for this typeof storm. 4 Guidance to overcome thisshortcoming is given in Section 3.5.The 2000, 2003, and 2006 IBC rely on severalreferenced standards and test methodsdeveloped or updated in the 1990s. Priorto adoption, most of these standards andtest methods had not been validated by actual building performanceduring design level wind events. The hurricanes of 2004and 2005 provided an opportunity to evaluate the actual performanceof buildings designed and constructed to the minimumprovisions of the IBC. Building performance evaluations conductedby FEMA revealed the need for further enhancements:m A limitation of the 2006 IBC pertains to some of the testmethods used to assess wind and wind-driven rain resistanceof building envelope components. However, before this codelimitation can be overcome, research needs to be conductedand new test methods need to be developed.The International Code Council (ICC)is developing a consensus standard,ICC/NSSA Standard for the Design andConstruction of Storm Shelters, to providebasic requirements for the design andconstruction of emergency shelters in areasaffected by hurricanes and tornadoes. Ifit is adopted by a community when itbecomes available in early 2007, it willprovide design and construction standardsfor buildings intended to resist the impactof high winds and wind-borne debris. Thisstand-alone standard will be linked to theIBC and IRC. It is the intent of the ICCthat the shelter standard be incorporatedby reference into the IBC and IRC in2009. FEMA should be consulted prior todesigning or constructing shelters to theICC/NSSA standard with FEMA fundsto ensure all program requirements aremet, as some components may need tobe designed to stricter criteria than thoseincluded in the consensus standard.4. Except for glass breakage, code-compliant buildings should not experience significant damage during weak tornadoes.MAKING CRITICAL FACILITIES SAFE FROM High Wind3-21