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www.sname.org/sname/mt July 2012 Learn More For more information on pedestrian dynamics modelling and simulation, check out the following resources. Azzi, C. and Vassalos, D., ?Design for ship -board re hazards assessment,? 10th International Marine Design Conference (IMDC), Volume 1 (2009). Azzi, C., Pennycott, A., Mermiris, G., and Vassalos, D., ?Evacuation simulation of shipboard re scenarios.? PROCEEDINGS , Fi re and Evacuation Modeling Technical Conference (2011). IM O, ?Interim guidelines for evacuation analyses for new and existing passenger ships.? MSC/Circ. 1033 (2002). IMO, ?Guidelines for evacuation analysis for new and existing passenger ships,? MSC.1/ Circ 1238 (2007). Pennycott, A, and Hi, Y., ?Evacuability of a ooded passenger ship.? 4th international Maritime Conference on Design for safety (2010). Vassalos, D., Kim, H., Christiansen, G., and Majumder, J., ?A Mesoscopic Model for Passenger Evacuation in a Virtual Ship- Sea Environment and Performance-Based Eva luation.? Pe destrian and Evacuation Dynamics (2001). no longer use the entire width of the space for egress. Furthermore, people tend to leave a larger space between themselves and the person in front. In the evacuation simulation software, the agents moving up and down stairs must stay close to the (lower) wall of the spaces to mimic the use of the handrails, and try to maintain a distance of at least 0.5 m from the person in front. Eect of re For re scenarios, the main parameters are heat, smoke, and toxicity. ese will aect agents by slowing them down (reduced visibility because of smoke) or partially or totally incapacitate them (heat and toxic gases such as carbon monoxide and car -bon dioxide. Heat and toxicity are treated by calcu -lating the cumulative fractional eective dose (FED) and assigning values to dier -ent health states as shown below. In addition, in a regular evacuation simulation, each passenger is assigned a reaction time and will not start mov -ing until this time has elapsed. However, a passenger directly exposed to high tem -perature or toxicity will start moving immediately, so the reaction time will be adjusted accordingly. Other potential uses The use of evacuation simulation is not restricted to evaluating the evacuability of existing ships. It can also be used to design safe and effective routes for circulation during normal conditions as well as eective egress routes during adverse conditions. For larger ships, it also can help decide the loca -tion of shops and other facilities onboard to maximize accessibility. Loading and unloading of ships at ter -minals, abandonment of oshore platforms, buildings, stadiums, and so on, are all gen -erally scenarios where pedestrian dynamics is applicable as a modeling tool. Real-world accidents show that sim -plied evacuation simulation, in which the eects of hazards are accounted for only with a safety factor, does not prepare passengers or crew for what could happen in a real emergency situation. ere is a need for a better representation of reality. For this, integration of a wider range of human behavior in emergency situations is needed, along with a better assessment of the eects that hazards such as re and flooding have on the people onboard. Validation data are also crucial and are much needed for better accuracy in the predictions of evacuation simulation. MTDracos Vassalos is professor of maritime safety in the Depart -ment of Naval Architecture and Marine Engineering of the University of Strathclyde, and the director of the Ship Stability Research Centre. Yasmine Hi is a research assistant at the Ship Stability Research Centre. FED range In jury type 0 FE D < 0.3 Ne gligible 0.3 FE D < 0.7 Mil d injury 0. 7 FE D < 1Se rious injury 1 FE DFat ality Passengers and crew heading towards their as sembly stations during an evacuation drill.