2.1 Design scenario (BE)
Fire blocks evacuation route
Design scenario in brief
A fire starts in an evacuation route and can potentially block the evacuation route.
Demonstrate that the level of safety is at least equivalent to the Deemed-to-Satisfy Provisions.
2.1.1 Design scenario description
This design scenario addresses the concern that an evacuation route may be blocked due to proximity of the fire source.
For each room/space within the building, assume that the fire source is located near the primary evacuation route and that it prevents occupants from leaving the building by that route. Fire in evacuation rout es can be the result of an accidental or deliberately lit fire.
In order to be regarded as alternative evacuation routes, the evacuation routes must be separated from each other and must remain separated until reaching a final exit in accordance with D1.5, or as demonstrated equivalent through analysis.
Active and passive fire safety systems in the building must be assumed to perform as intended by the design.
The fire safety engineer needs to consider fire source locations that prevent the use of exits in evacuation routes.
Fire characteristics (e.g. HRR) and analysis need not be considered in this design scenario as the fire is assumed to physically block the evacuation route. It may be assumed that occupant tenability criteria cannot be met where fire plumes and flames block an evacuation route.
2.1.2 Typical method or solution
The requirements of this design scenario can be demonstrated by analysis that checks whether or not a second evacuation route is required.