Work out evacuation time instantly with clear inputs, formula shown and shareable results.
Evacuation time is the walking time to reach an exit at about 1.2 metres per second, plus the queuing time as occupants pass through the exits at the stated flow rate. Losing one exit does not add a third to the time, it adds half again to the flow component, which is why blocked exits matter so much more than long corridors.
Flow time
minutes = occupants / (exits x flow rate per exit)
Travel time
minutes = travel distance / (1.2 m/s x 60)
A simplified hydraulic model for orientation only. Real evacuation analysis requires a competent fire engineer.
minutes = occupants / (exits x flow rate per exit). Evacuation time is the walking time to reach an exit at about 1.2 metres per second, plus the queuing time as occupants pass through the exits at the stated flow rate.
Losing one exit does not add a third to the time, it adds half again to the flow component, which is why blocked exits matter so much more than long corridors.
Enter number of occupants, usable exits, flow rate per exit, longest travel distance to an exit. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.