Revit Beyond BIM has posted the steps and packages necessary to perform analysis on some model lines in Revit that represent the evacuation path. Also, Dynamo is used to create an analysis display for the accumulated distance of travel.

You can download the Revit file and Dynamo script by clicking on this link.

Source:
https://revitbeyondbim.wordpress.com/2016/04/22/evacuation-path-analysis-with-dynamo/