Är utrymningsschablonerna vid brandteknisk dimensionering säkra?

Sammanfattning: This report investigate evacuation safety in business premises. A number of rooms have been designed by old Swedish building regulations, Nybyggnadsreglerna, NR, 1988 as handbook. When NR doesn’t corresponds with the building regulations of today, Boverkets byggregler, BBR 94, the rules in BBR will be followed. The rooms have been chosen in a way so it will be possible to study the effects on the evacuation safety for different room heights, the relationship between the floor area and the room height, if an emergency exit is blocked, different evacuation alarms and when smoke evacuation is installed. To be able to examine the safety in the rooms where the fire safety is designed with NR 1988 as handbook an expression for the safety margin has been determined. The safety margin will be calculated as time taken to reach untenable conditions minus the total escape time. The total escape time consists of the time taken to detect the fire, the response and behaviour time and the time required to move to a safe location. When the safety margin is zero or more can a safe evacuation take place, all people can evacuate before untenable conditions. The safety margin has been calculated with probabilistic uncertainty analysis. This means that the variables that effect the time to untenable and/or the total escape time are described with distributions. The result shows that the evacuation safety varies a lot in the examined rooms.