8.2.1 General

Fire scenarios describe factors critical to the outcome of fires, such as fire protection features, ignition sources, the nature and configuration of the fuel, ventilation, characteristics and locations of occupants, and conditions of the supporting structure and other equipment. A fire scenario might also include circumstances preceding ignition to the extent that they are necessary to help describe subsequent events.

A fire scenario represents one of a set of fire conditions that are thought to be threatening to a building, its occupants, and its contents. This description should therefore address the state of the building, its contents, and its occupants at the time of the fire.

Possible fire scenarios are the basis for design fire scenarios, which in turn are used to evaluate trial designs.

8.2.2

For a given possible fire scenario, many factors might affect fire development. These different factors might include the following:

• Form of ignition source

• Type of fuel first ignited

• Location of fire

• Effects of compartment geometry

• The initial status of doors and windows (whether open or closed) and the time in the possible fire scenario at which that status changed

• Ventilation, whether natural (e.g., doors and windows) or mechanical (e.g., HVAC)

• Type of construction and lining materials

• Form of intervention (e.g., occupants, fire suppression systems, and the fire department)

See Appendix D for an example of a possible fire scenario.

8.2.3 Possible Fire Scenario Characteristics