Effects of Smoke on Evacuation Martin Lopušniak 1, a

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1 Advanced Materials Research Online: ISSN: , Vol. 899, pp doi: / Trans Tech Publications, Switzerland Effects of Smoke on Evacuation Martin Lopušniak 1, a 1 TU Košice SvF, Vysokoškolska 4, Košice, Slovakia a martin.lopusniak@tuke.sk Keywords: Smoke, Evacuation, Modeling, Building. Abstract. Smoke is often presents during a fire. It affects efficiency of evacuations in buildings. Slovakian national standards do not consider any fire products in evacuation calculations. The paper presents results of evacuation calculations with considerations of smoke. Calculations are done with the evacuation model buildingexodus on a hotel building. Results show that prolongation of evacuation time is up to 162%. Results show that the prolongation of evacuation time is up to 162 %, and also show the prolongation of evacuation time do not necessary depend on size, but on position of smoke. Introduction Smoke is often presents during a fire. Effect of smoke on people is difficult to evaluate. But in case of evacuations smoke is a key factor which influences time of evacuation. Movement in smoke laden environment is complicated, unpredictable and experimentally unverifiable. Influences of smoke on human behavior in smoke laden environment has been the subject of several works [1,2,3,4]. There are some evacuation models which allow to model smoke within evacuation modeling [5]. The aim of this work is to analyze the impact of smoke on a process and time of evacuation. Evacuation model buildingexodus (BE) was chosen for the problem solution. Building and evacuation scenarios Building. This is a twelve-floor building - hotel. Rooms are located on the third to the twelfth floor. The building is designed with two stairways for evacuation of all persons (Fig. 1, 2). Fig. 1 Typical floor plan and the staircase position Evacuation scenarios. Modifications of the model were coded in the last subparagraph (E). 340 persons (default BE) without physical limitations are expected in the building. Nine modifications of the model, labeled E1 - E9, were carried out in the analysis. They represent different scenarios for the spread of smoke in the building. The effect of smoke limited only visibility. Galea and Gwynne described the mechanism of solving of the tasks [6,7]. The intended smoke contains no irritable substances. E1 is the basic modification, which represents the impact of smoke-free building. Modifications E3 and E4 represent a situation, where smoke is in the area of the hotel corridor (8 th E3 or 12 th floor E4). For modifications E2, E5, E6, E7, E8 and E9 is the smoke located just in the staircase area, respectively E2-1 st to 12 th floor; E5-1 st to 6 th ; E6-1 st to 3 rd ; E7-1 st to 6 th + 40 % of people redirected to second staircase;, E8 (9 th to 12 th )a E9 (6 th to 12 th ). All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, (ID: , Pennsylvania State University, University Park, USA-10/05/16,15:54:28)

2 540 EnviBUILD Buildings and Environment 2013 Fig. 2 Building section with schematic smoke position situation. It is based purely on literature values [1,2,3]. In the case of E7 modification a comp. algorithm is used, which allows to specify the percentage of persons who due to reduced visibility use another exit as their priority exit. In this modification a system, when 40 % of all people will change the direction of escape at visibility less than 2 m, was used. The maximum visibility was 1.15 m in all modifications. This value is purely theoretical, and it does not represent any specific Results The achieved results can be divided into two groups. The first group represents theoretical fires on the 8 th -floor corridor (E3) and 12 th floor (E4). Modifications E1 and E3 show no differences. The average evacuation time was t avg = and s. But the E4 modification has the longer evacuation time by more than 26 s, t avg = 256 s (Fig. 3a). The effect of evacuation time extension does not occur in the E3 case. It is caused by the fact that persons on the 8 th floor need less time to arrive to the staircase, as people arriving from the 12 th floor to the 8 th floor. Despite the presence of smoke on the 8 th floor this time is shorter. Extension of the evacuation time is only for the E4, when people on the 12 th floor are affected by smoke. In this case it leads to the longer evacuation time (Fig. 3b), but only in its final stage. The result points to the extension of the evacuation time of 6.5 s per floor R1P1M1G1E1 210 R1P1M1G1E1 R1P1M1G1E3 R1P1M1G1E4 Simulation Sim 1 Sim 2 Sim 3 Sim 4 Sim 5 AVG a) b) Fig.3 a) Evacuation time (s) for E1, E3, E4 modifications; b) Cumulative curve of the evacuation time (s) for E1, E3, E4 modifications Evacuation time (s) R1P1M1G1E4 R1P1M1G1E3

3 Advanced Materials Research Vol The second group of results is represented by theoretical fires on the staircase. In this group the results, the impact of smoke on evacuation time caused significant differences. The lowest extension of evacuation time was 41 % of time for evacuation in the E1 modification. The largest extension of evacuation time was 162 %. The overview of the evacuation times is shown in the Figure 4a. An interesting observation is that the differences between the achieved evacuation times are very small in the case of E2, E5 and E6 modifications. It says that the evacuation time is influenced not only by the extent of smoke, but it is mainly influenced by the location of smoke from fire. In the case of the E6 modification smoke contamination is only on levels 1 st to 3 rd floor, but the evacuation time is shorter only by 25 seconds from the evacuation time for the E2 modification, which represents the smoke contamination in the whole staircase. From the point of smoke contamination, two model modifications were made assuming development of fire in the upper part of staircase (E8 and E9). The results show that evacuation time extension is also caused by smoke. However, the extension of evacuation time is not as long as in the case of smoke position on lower floors E1 E2 E5 E6 E9 E8 Simulácia Sim 1 Sim 2 Sim 3 Sim 4 Sim 5 AVG a) b) Fig. 4 a) Summary overview on the evacuation times (s) of the selected model modifications; b) the time course of evacuation through the doors D1 and D2. Despite the six upper floors are loaded with smoke, the evacuation time is not extended as in the case of six lower floors (t, E5 = 600s, t, E9 = 420s). The explanation gives time progress of evacuation in the Figure 4b. The figure presents a mutual comparison of simulations E8, E9 and E5. Evacuation time progresses for the second door (D1) leading to an open area are added to the Figure 4b for a comparison. The mutual comparison shows that the beginning of evacuation (time to, or s) is the same in all cases excepting the E5. A change occurs at the time, when people from areas contaminated by smoke start to go through the exit (D2). The evacuation time was subsequently extended, and progresses E8-D2 and E9-D2 are parallel with the E5-D2 progress. BE offers a utility, when persons are redirected in a case that their escape route is contaminated by combustion gases. This means that some persons from the building are redirected to another exit from the building, in which these persons do not have to pass through any smoke contaminated area. This is the very interesting utility of BE. The E5 and E7 simulations were used for the analysis of persons to be redirected in the building. Because persons were redirected, the evacuation time was shortened by s. The reason is shown in the Figure 5, where the change in the progress of evacuation time is clear at the time t = s. There is a redirection of first persons to the door D1 at Evacuation time (s) E8-D2 E8-D1 E9-D2 E9-D1 E5-D2

4 542 EnviBUILD Buildings and Environment 2013 this time. The increase in the number of evacuees going through the D1 door from 180 up to 219 persons is also clear from the Figure 5. Although the increase in the number of persons extends evacuation time through the D1 door, simultaneously it shortens the evacuation time through the D2 door E5-D2 E5-D1 E7-D2 E7-D Fig. 5 Cumulative curve of the evacuation time (s) for E5 and E7 modifications Conclusion This paper presents an analysis of impact of smoke-contaminated escape route to evacuation time, and evacuation progress in a hotel building. The results showed that the location of smoke contamination in the building is more significant than the extent of smoke contamination. Generalization of time extension rate of evacuation is not possible, because it also depends on a location of contamination in a building, which can be optional. References [1] J. Bryan, Behavioral Response to Fire and Smoke, in: P.J. DiNenno (Eds), SFPE Handbook of Fire Protection Engineering, second ed., NFPA, Quincy, 1995 pp [2] T. Jin, Visibility through fire smoke. J.of Fire Flammability. 9 (1978) [3] P.A. Rubini, Q. Zhang, J.B. Moss, Simulation of Visibility in Smoke Laden Environments, in: InterFlame 7, IFSA, London, 7, pp [4] T. Paulsen, The Effect of Escape Route Information on Mobility and Way Finding under Smoke Logged Conditions, in: Proceedings of the Fourth International Symposium of International Association for Fire Safety Science, IAFS, Ottawa, 1994, pp [5] E.D. Kuligowski, E.D. Peacock, Review of Building Evacuation Models : NIST Technical Note 1471 [online], Available from: [6] E.R. Galea, Principles and Practice of Evacuation Modeling, 10th ed., CMS Press, London, 9. [7] S. Gwynne, E.R. Galea, P.J. Lawrence, L. Filippidis, Modeling Occupant Interaction with Fire Conditions Using the buildingexodus Evacuation Model, Fire Safety J. 36 (1),

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