scholarly journals Numerical studies on fire hazards of elevator evacuation in supertall buildings

2018 ◽  
Vol 28 (2) ◽  
pp. 247-263 ◽  
Author(s):  
N. Cai ◽  
W.K. Chow

Long evacuation time is a key fire safety concern for crowded supertall buildings. Elevator evacuation appears to be the only choice but fire safety provisions are not specially designed for the use of elevators. A fire safe elevator system was proposed earlier for supertall buildings by providing elevator accessible on each floor level and passing through the refuge place. The fire hazard associated with this design has been studied numerically through an example building in this paper. Smoke spread to the elevator system was considered in the study. The effect of ventilation of the shaft, stack effect and wind effect on smoke movement were studied by empirical equations in fire engineering and justified by computational fluid dynamics. Different designs of smoke extraction with pressurization system were evaluated by analysing the smoke dispersion and pressure distributions. The effect of fire at different heights on smoke spread was also investigated. Results show that the smoke extraction system can only delay smoke spread to the elevator shaft near the fire source for a short time. The “four-floor approach” pressurization system can confine the smoke in the area of fire floor for a sufficiently long time period for safe evacuation.

Author(s):  
Tomaz Hozjan ◽  
Kamila Kempna ◽  
Jan Smolka

Actual and future concerns in fire safety in buildings and infrastructure are challenging. Modern technologies provide rapid development in area of fire safety, especially in education, training, and fire-engineering. Modelling as a tool in fire-engineering provides possibility to design specific fire scenarios and investigate fire spread, smoke movement or evacuation of occupants from buildings. Development of emerging technologies and software provides higher possibility to apply these models with interactions of augmented and virtual reality. Augmented reality and virtual reality expand effectivity of training and preparedness of first (fire wardens) and second (firefighters) responders. Limitations such as financial demands, scale and scenarios of practical training of first and second responders are much lower than in virtual reality. These technologies provide great opportunities in preparedness to crisis in a safety way with significantly limited budget. Some of these systems are already developed and applied in safety and security area e.g. XVR (firefighting, medical service).


2020 ◽  
pp. 26-35
Author(s):  
Денис Валерьевич Зобков ◽  
Александр Алексеевич Порошин ◽  
Андрей Александрович Кондашов ◽  
Евгений Васильевич Бобринев ◽  
Елена Юрьевна Удавцова

Проанализирован международный опыт реформирования проверок соблюдения требований пожарной безопасности и внедрения риск-ориентированного подхода. Разработана модель отнесения объектов защиты к категориям риска в зависимости от вероятного причинения вреда, который рассчитывается исходя из количества погибших и травмированных при пожарах людей. Сформулированы критерии отнесения объектов защиты к категориям риска. Выполнен расчет категорий риска для групп объектов, однородных по группам экономической деятельности и классам функциональной пожарной опасности. Проведено сравнение с существующей классификацией объектов защиты по категориям риска. The international experience of reforming of fire safety compliance checks and implementing a risk-based approach is considered. There are presented methodological approaches to calculating the risk of causing harm (damage) in buildings (structures) as a result of fire for the purpose of assignment of buildings and structures according to risk categories as well as justification of the frequency of scheduled inspections at these facilities. There is calculated the probability of fire occurrence for a group of objects of protection that are homogeneous by type of economic activity and functional fire hazard classes in order to assign objects of protection to certain risk categories. The social damage expressed in the death and injury of people as a result of fire is also calculated in order to assign objects of protection to certain risk categories. Classification of objects of protection according to the risk categories is performed using the indicator of the severity of potential negative consequences of fires. This indicator characterizes the degree of excess of the expected risk of negative consequences of fires for the corresponding group of objects of protection in relation to the value of the permissible risk of negative consequences of fire. The permissible risk of negative consequences of fires is calculated on the basis of statistical data, taking into account the value of the individual fire risk of exposure of critical values of fire hazards on person in buildings and structures. The criteria for assigning groups of objects of protection to the appropriate risk categories are formulated on the basis of formation of distribution of numerical values of the severity of potential negative consequences of fires. There are carried out the assessment of the severity of potential negative consequences of fires for objects of protection that are homogeneous by type of economic activity and functional fire hazard classes, and also the risk categories of the corresponding groups of objects are determined. The proposed classification of objects of protection according to risk categories is compared with the existing classification. The obtained results of calculations showed that scheduled inspections of objects of protection by the Federal state supervision bodies, depending on the assigned risk category and with corresponding frequency, have significant role in improving the level of fire safety of objects. The decrease in the intensity of scheduled inspections, at the same time, may lead to a corresponding decrease in the level of fire protection of objects.


2021 ◽  
Vol 30 (1) ◽  
pp. 16-31
Author(s):  
L. A. Koroleva ◽  
A. G. Khaydarov ◽  
G. K. Ivakhnyuk ◽  
Yu. E. Akterskiy

Introduction. Problems of fire safety of dangerous goods (DG) in the process of their rail transportation have not been fully resolved. The flammability assessment of substances and materials is insufficiently impartial; an integrated indicator, that allows to apply a consolidated methodological standpoint to improve their energy efficiency and environmental/fire safety is unavailable.The purpose of this work is to substantiate the feasibility and advantages of the exergy approach to assessing the fire hazard of the exhaust gas emitted from railroad transport.Materials and methods. The use of the flammability potential as an integrated indicator of the fire hazard of cargoes has a number of limitations. The exergy approach has a strong potential if applied to the assessment and prediction of fire hazards. Present-day and potential railroad cargoes serve as examples that substantiate the feasibility of this approach.Results and its discussion. Dependences between fire hazard indicators (flash points, flame propagation limits, auto-ignition points, heat of combustion) demonstrated by the components of liquid and gaseous fuels and the chemical exergy were identified.A study of changes in the physical exergy triggered by spills and combustion were illustrated by liquefied natural gas and liquefied hydrocarbon gases having various compositions. Physical exergy change patterns depending on the temperature and pressure of the above products were developed.For self-ignitable cargoes, dependences between the physical exergy and activation energy, critical ambient temperature, and heat capacity of self-heating materials were identified. The influence of thermal conductivity and humidity coefficients on the exergy value is established.Exergy changes were determined depending on the elemental composition of solid municipal waste, ash, volatile matter and fixed carbon content. Polymers and rubbers have the highest values of this indicator.An exergy indicator was introduced to assess fire and environmental hazards of substances and materials; it serves as the basis for the classification of cargoes.Conclusions. The use of the exergy indicator allows to increase the objectivity of assessments and take account of technical, economic, environmental criteria and indicators of fire hazards within an integrated system.


2019 ◽  
Vol 4 (1) ◽  
pp. 1-23 ◽  
Author(s):  
Venkatesh Kodur ◽  
Puneet Kumar ◽  
Muhammad Masood Rafi

Purpose The current fire protection measures in buildings do not account for all contemporary fire hazard issues, which has made fire safety a growing concern. Therefore, this paper aims to present a critical review of current fire protection measures and their applicability to address current challenges relating to fire hazards in buildings. Design/methodology/approach To overcome fire hazards in buildings, impact of fire hazards is also reviewed to set the context for fire protection measures. Based on the review, an integrated framework for mitigation of fire hazards is proposed. The proposed framework involves enhancement of fire safety in four key areas: fire protection features in buildings, regulation and enforcement, consumer awareness and technology and resources advancement. Detailed strategies on improving fire safety in buildings in these four key areas are presented, and future research and training needs are identified. Findings Current fire protection measures lead to an unquantified level of fire safety in buildings, provide minimal strategies to mitigate fire hazard and do not account for contemporary fire hazard issues. Implementing key measures that include reliable fire protection systems, proper regulation and enforcement of building code provisions, enhancement of public awareness and proper use of technology and resources is key to mitigating fire hazard in buildings. Major research and training required to improve fire safety in buildings include developing cost-effective fire suppression systems and rational fire design approaches, characterizing new materials and developing performance-based codes. Practical implications The proposed framework encompasses both prevention and management of fire hazard. To demonstrate the applicability of this framework in improving fire safety in buildings, major limitations of current fire protection measures are identified, and detailed strategies are provided to address these limitations using proposed fire safety framework. Social implications Fire represents a severe hazard in both developing and developed countries and poses significant threat to life, structure, property and environment. The proposed framework has social implications as it addresses some of the current challenges relating to fire hazard in buildings and will enhance overall fire safety. Originality/value The novelty of proposed framework lies in encompassing both prevention and management of fire hazard. This is unlike current fire safety improvement strategies, which focus only on improving fire protection features in buildings (i.e. managing impact of fire hazard) using performance-based codes. To demonstrate the applicability of this framework in improving fire safety in buildings, major limitations of current fire protection measures are identified and detailed strategies are provided to address these limitations using proposed fire safety framework. Special emphasis is given to cost-effectiveness of proposed strategies, and research and training needs for further enhancing building fire safety are identified.


Author(s):  
Mufida Mkharem ◽  
Nor Mariah Adam ◽  
Eris Elianddy Supeni

Fire accidents are common accidents amongst residential house occupants in Libya. Some of the factors that can mitigate fire accidents in Libyan residential houses include fire safety awareness and knowledge. This study investigated the level of awareness and knowledge of fire safety amongst residential house occupants in Libya. The possibility and consequences of fire hazards and risk existing in residential houses in Libya were also studied. Experimental data obtained for 1.5 m/s and 3.5 m/s as walking and running evacuation time, respectively amongst residential house occupants in Libya were also compared. The sample consist of 90 respondents with instruments of fire safety awareness and knowledge, fire hazard and consequences, and the involvement of residential house occupants in fire emergency. Statistical analysis was performed at p < 0.05 to determine the levels of residential awareness and knowledge regarding fire safety and the hazard and consequences. The findings illustrated that the items were highly reliable (α > 0.7) and normally distributed. Also, the results illustrated that the majority of residential house occupants in Libya have fair level of fire safety awareness and knowledge with overall percentage of 80% and 90%, respectively. On the other hand, the results further showed that majority of residential house occupants have good level of fire emergency involvement with 90%. This paper proposes a fire safety assessment method which may form the basis of future fire safety practice in Libya.


2020 ◽  
Vol 90 ◽  
pp. 19-31
Author(s):  
D. V. Zobkov ◽  
◽  
A. A. Poroshin ◽  
A. A. Kondashov ◽  
◽  
...  

Introduction. A mathematical model is presented for assigning protection objects to certain risk categories in the field of fire safety. The model is based on the concepts of the probability of adverse effects of fires causing harm (damage) of various extent and severity to the life or health of citizens, and the acceptable risk of harm (damage) from fires. Goals and objectives. The purpose of the study is to develop the procedure for assigning protection objects to a certain category of risk of harm (damage) based on estimates of the probability of fires with the corresponding severity consequences, to determine the acceptable level of risk of harm (damage) due to the fires, to calculate and develop numerical values of criteria for assigning objects of protection to the appropriate risk categories. Methods. The boundaries of the intervals corresponding to certain risk categories are determined by dividing the logarithmic scale of severity of adverse effects of fires into equal segments. Classification methods are used to assign objects of protection to a specific risk category. Results and discussion. Based on the level of severity of potential negative consequences of a fire, risk categories were determined for groups of protection objects that are homogeneous by type of economic activity and by functional fire hazard classes. The risk category for each individual object of protection is proposed to be determined using the so-called index of "identification of a controlled person" within a group of objects that are homogeneous by type of economic activity and class of functional fire hazard. Depending on the risk category, the periodicity of planned control and supervision measures in relation to the specific object of protection under consideration is determined, taking into account its socio-economic characteristics and the state of compliance with fire safety requirements by the controlled person. Conclusions. To develop criteria for classifying protection objects that are homogeneous in terms of economic activity and functional fire hazard classes, the probability of negative consequences of fires, that are causing harm (damage) of various extent and severity to the life or health of citizens, and the acceptable risk of causing harm (damage) as a result of fires, is used. The risk category for each individual object of protection is determined taking into account socio-economic characteristics of the object that affect the level of ensuring its fire safety, as well as the criteriaof integrity of the subordinate person that characterize the probability of non-compliance with mandatory fire safety requirements at the object of protection. Calculations are made and numerical values of criteria for assigning protection objects that are homogeneous in terms of economic activity and functional fire hazard classes to a certain category of risk are proposed. Key words: object of protection, probability of fire, acceptable level of risk, risk category, dangerous factor of fire, death and injury of people.


2021 ◽  
Vol 11 (6) ◽  
pp. 2590
Author(s):  
Samson Tan ◽  
Darryl Weinert ◽  
Paul Joseph ◽  
Khalid Moinuddin

Given that existing fire risk models often ignore human and organizational errors (HOEs) ultimately leading to underestimation of risks by as much as 80%, this study employs a technical-human-organizational risk (T-H-O-Risk) methodology to address knowledge gaps in current state-of-the-art probabilistic risk analysis (PRA) for high-rise residential buildings with the following goals: (1) Develop an improved PRA methodology to address concerns that deterministic, fire engineering approaches significantly underestimate safety levels that lead to inaccurate fire safety levels. (2) Enhance existing fire safety verification methods by incorporating probabilistic risk approach and HOEs for (i) a more inclusive view of risk, and (ii) to overcome the deterministic nature of current verification methods. (3) Perform comprehensive sensitivity and uncertainty analyses to address uncertainties in numerical estimates used in fault tree/event trees, Bayesian network and system dynamics and their propagation in a probabilistic model. (4) Quantification of human and organizational risks for high-rise residential buildings which contributes towards a policy agenda in the direction of a sustainable, risk-based regulatory regime. This research contributes to the development of the next-generation building codes and risk assessment methodologies.


2021 ◽  
Vol 13 (10) ◽  
pp. 5369
Author(s):  
Rajesh Khatakho ◽  
Dipendra Gautam ◽  
Komal Raj Aryal ◽  
Vishnu Prasad Pandey ◽  
Rajesh Rupakhety ◽  
...  

Natural hazards are complex phenomena that can occur independently, simultaneously, or in a series as cascading events. For any particular region, numerous single hazard maps may not necessarily provide all information regarding impending hazards to the stakeholders for preparedness and planning. A multi-hazard map furnishes composite illustration of the natural hazards of varying magnitude, frequency, and spatial distribution. Thus, multi-hazard risk assessment is performed to depict the holistic natural hazards scenario of any particular region. To the best of the authors’ knowledge, multi-hazard risk assessments are rarely conducted in Nepal although multiple natural hazards strike the country almost every year. In this study, floods, landslides, earthquakes, and urban fire hazards are used to assess multi-hazard risk in Kathmandu Valley, Nepal, using the Analytical Hierarchy Process (AHP), which is then integrated with the Geographical Information System (GIS). First, flood, landslide, earthquake, and urban fire hazard assessments are performed individually and then superimposed to obtain multi-hazard risk. Multi-hazard risk assessment of Kathmandu Valley is performed by pair-wise comparison of the four natural hazards. The sum of observations concludes that densely populated areas, old settlements, and the central valley have high to very high level of multi-hazard risk.


2012 ◽  
Vol 468-471 ◽  
pp. 1753-1757
Author(s):  
Yang Wei Shao ◽  
Shih Feng Kao ◽  
Neng Chun Yu ◽  
Yu Shiang Wu ◽  
Chi Jan Huang ◽  
...  

Although meeting the regulations of the time, early buildings are prone to fire hazards, such as damages to the fire zones, changes of floor entrances and exits, locked emergency exit doors, blocking of entrances and exits by vehicles, increased fire sources, dense population in the buildings, due to insufficient professional knowledge and technology in fire prevention. Once a fire occurs, it can result in major casualties, serious loss of social costs, as well as environmental and social issues. This study investigated 17 major fire cases occurring in residential-commercial composite buildings in the last 20 years in Taiwan. The fire hazard factors were determined based on expert review. The findings can serve as a reference for fire agencies in promoting fire prevention.


Sign in / Sign up

Export Citation Format

Share Document