• Journal of the Korea Safety Management & Science
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• v.22 no.3
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• pp.15-21
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• 2020

This study analyzed the evacuation time in indoor stadiums when exits that automatically open/close when the fire sensor is triggered are installed as a means to improve the problem of closing certain exits. Firstly, when spectators on the 2nd floor stands exit through the 1st floor exits, the RSET of all inhabitants was 529.8 seconds when the automatic opening/closing exits are broken and employees are not present. Secondly, when spectators on the 2nd floor stands exit through the 1st floor exits, the RSET of all inhabitants was 445 seconds when the automatic opening/closing exits with 750mm width are working but employees are not present. Lastly, when spectators on the 2nd floor stands exit through the 1st floor exits, the RSET of all spectators was 337 seconds when the automatic opening/closing exits with 1,500mm width are working and employees are present. As a result, it was revealed that the evacuation time is shortened when the automatic opening/closing exits are working. Additional comparative studies with actual simulations of people evacuating an indoor stadium and firefighting simulations considering smoke flow are necessary.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.3
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• pp.89-94
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• 2009

The stack effect in high-rise buildings is expected more significant at nights in winter due to the large temperature difference between the inside and outside of the buildings. However, the existence of large openings such as natural ventilators on the floor may effect the position of neutral plane, smoke spread at fire and thus obstruct the door openings for rescue. In this paper, the vertical and horizontal pressure distribution with different openings of natural smoke ventilators was experimentally analyzed by investigating pressure differentials.

• Fire Science and Engineering
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• v.26 no.5
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• pp.92-98
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• 2012

This study analyzed the effect of zoning on the distribution of pressure differentials caused by stack effect and air pressurization in a center core type of 80 story super-tall building. The results showed that maximum pressure difference more than 250 Pa can be generated by stack effect without zoning. Zoning of stairwell only resulted in 10 Pa reduction of maximum pressure difference, however, zoning of both stairwell and EV shaft especially at the same floor revealed 50 % reduction in stack effect. It was also analysed that the minimum required air flow rate occurred when the stairwell temperature reached 50 % of temperature difference between indoor and outdoor.

• Fire Science and Engineering
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• v.22 no.1
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• pp.54-60
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• 2008

The occurrence of fires in heavily populated multiplex buildings is a serious concern. It causes a great threat to many people and a serious social problem. Whenever this kind of fire happens, the authorities are busy preparing partial countermeasures to control the crisis situations. Luckily, the government has enforced a special law regarding safety supervision of majority-used buildings to prepare the basic countermeasures for the buildings' safety. Recently, the multiplex buildings which have multi type compounds have increased in size by getting bigger and bigger. As there are many people who would need to escape and the complicated structures like mazes in buildings of this type, it is not only difficult to prevent a fire but also easy to cause a large loss of lives. For a better fire safety supervision of the buildings, there needs to be passers and owners' good sense of safety, fire proof of the buildings and education of the fire authorities.

• Fire Science and Engineering
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• v.24 no.4
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• pp.69-78
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• 2010

In this study, Fire Hazards were evaluated through computer simulation using FDS program for an apartment fire accident. The results of fire simulation showed that the maximum heat release rate in the case of no sprinklers activation was 7,700 kW which was about 16 times of that in the case of sprinklers activation, 497 kW and there was a very high fire hazard due to the backdraft phenomenon when the door of fire room was forced to open. Regarding the hazard time of fire room temperature and detection time of detectors, available evacuation time was 32.5 seconds of minimum to 53.5 seconds of maximum. In the case of sprinklers activation, fire hazard in the apartment was showed to be very low due to the fire control by the spray cooling of sprinklers. This study shows that what a important function for fire safety is the activations of fire sprinkler system and emergency alarm system and what a large loss can cause if these systems don’t activate in fire accidents.

• Fire Science and Engineering
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• v.21 no.3
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• pp.15-23
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• 2007

In the events of a fire in the residential building, highly flammable polyurethane foam sofa produce toxic smokes. In this type of fire, the residents of the building can be gotten into the difficulties of evacuating from the fire places or may be to death due to a lot of hot toxic gases. In this study, CFD simulations were carried out to study the effects of the openings of stairwell on the fire characteristics of fire room and stairwell. Also, analysis of fire hazard based on the tenability limits of fire and FED(fractional effective dose) was performed to evaluate the life safety of the residents of the building. In the fire room, maximum temperature was about $290^{\circ}C$, maximum CO concentration was about 4,740 ppm, and the time to incapacitation of residents in fire room was about t=144 s. In the stairwell, temperature and CO concentration in the condition of openings to be open were even lower than those in it to be closed. Time to the tenability limit with respect to smoke visibility in the stairwell with openings, which was open, was shorter than that of it without openings to be open. It has been shown from this study that opening the stairwell openings is able to decrease the fire hazards to the life safety in the multi-story residential building fire.