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. 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 multi hazard 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.