This guideline contains qualitative and quantitative methods for management of the risk of extraordinary incidents in buildings. Specific subject areas of concern include air@ food@ and water. The extraordinary events addressed in this guideline include fire@ seismic events@ chemical and biological releases@ blast@ and other extraordinary hazards. The guideline will address extraordinary incidents from a multihazard perspective and will cover both intentional and accidental occurrences. The guideline addresses aspects of building performance that affect occupant health and safety@ including egress; chemical@ biological@ and radiological (CBR) protection; fire protection; smoke removal or purging; filtration; air quality; entrance paths for contaminants; and building envelopes. PURPOSE The purpose of this guideline is to provide guidance for the practical evaluation@ design@ and implementation of measures to reduce multiple risks in new and existing buildings.