During emergency condition

it’s important of evacuation time for the crowd safety in complex subway station.In this paper

a computational evacuation discrete time model（EDTM） is presented to analyze the building egress evacuation time problem.EDTM uses crowd flow theory and discrete computational methods to identify the width of egress that are available for occupants to exit

which is more accurate and practicable because the crowd flow rate is variable.A case of subway station staircase egress is chosen for the validity of EDTM

and the comparison of EDTM

previous model and computer simulation indicates that both the EDTM and the simulation curve are found to give better predictions than the previous model.Based upon the results

EDTM shows great value in dealing with subway station evacuation time calculation

egress performance design

emergency plan establishment and so on.