Introduction of a flame suppression pattern into integrated and zone models used to analyze the dynamics of hazardous factors of indoor fires

2021 ◽  
Vol 30 (2) ◽  
pp. 78-87
Author(s):  
D. A. Korolchenko ◽  
S. V. Puzach

Introduction. Fire risk calculation is performed to substantiate the compliance of space planning solutions of buildings and structures with fire safety requirements. The calculation of time needed for hazardous factors of fire to block evacuation routes is performed with account for unlimited fire propagation. The only system, whose operation is taken into account if the fire risk value is exceeded, is the smoke ventilation system. The operation of other fire safety systems is disregarded due to the unavailability of reliable engineering methods of analysis of their influence on fire escalation. The problem of development of modified mathematical models, used to analyze the fire escalation pattern, with account to be taken of the process of fire extinguishing and its influence on fire propagation, is relevant. The purpose of this research is to develop common principles that allow to take account of the pattern of fire suppression in solid materials and combustible liquids by fire extinguishing substances having various origins and degrees of dispersion, if the fire extinguishing substances are added to integrated and zone models of development of hazardous factors of fire escalation.Calculation methodology. The calculations are based on the equation compiled in furtherance of principles of conservation of mass and energy in the flame zone above the surface of the combustible material.Research results. The co-authors suggest general principles for the introduction of a flame suppression pattern into integrated and zone models used to analyze the evolution of hazardous factors of indoor fires. The coauthors present the main provisions and parameters needed to modify integrated and zone models in case of different methods of fire extinguishing. The co-authors have analyzed hazardous factors of fire with account for the flame suppression pattern.Conclusions. The co-authors applied the research findings to develop the modified integrated and zone models that allow to analyze the dynamics of hazardous factors of fire with account for the extinguishing of solid materials and combustible fluids by fire extinguishing substances having various origins and degrees of dispersion.

2018 ◽  
Vol 14 (2) ◽  
pp. 1-12 ◽  
Author(s):  
Dan Burlacu ◽  
Ion Anghel ◽  
Constantin Popa ◽  
Ionuţ Căşaru

Abstract This paper presents a global fire risk assessment by using fire simulation in an existing underground parking. The simulation is conducted with the Fire Dynamics Simulator, a Computational Fluid Dynamics (CFD) tool and the simulations are performed on a threedimensional model of the parking. Multiple parameters and factors are taken into account in this complex assessment, such as geometry data, ventilation openings (both mechanical and natural), fire detection and fire suppression details. The output of the case study is represented by a large array of data: the time for sprinkler activation, maximum temperatures, smoke flow and overall fire evolution. The intention of the authors is to provide a global fire risk assessment of the parking, based on the fire safety engineering principles.


Fire Safety ◽  
2019 ◽  
pp. 10-15
Author(s):  
O. I. Bashynskiy ◽  
M. Z. Peleshko ◽  
Yu. T. Sydnitsyn

Over the last year, the number of new buildings in Lviv has increased by 30%. Most of them are the high-rise buildings. In this regard, the problem of fire safety of such buildings appears sharper. In our time, one of the main requirements in building standards is to ensure the life safety. Fire safety is an integral part of the life safety. The main causes of the fires, difficulties of their liquidation, the problems of self-management, the reliability of the systems of fire water supply, fire barriers and the evacuation of people from high-rise buildings were analyzed in the article. The causes of the rapid spread of fires in multi-store buildings were revealed. The analysis of the example of fires clearly shows problems of fire safety, admitted at the stage of construction of the high-rise buildings. The actual situation in such buildings is characterized by the following disadvantages: the fire alarm system often is in an unfit condition because of dismantling of the fire alarm sensors by the residents; the common floor-corridors are blocked by additional partitions, causing difficulties in the work of the smoke exhaust systems; there are no self-closing doors and their sealing in the shelters, which allows smoke to spread freely in the house and creates the preconditions for rapid vertical fire spreading. The protection of people on evacuation routes is provided by a complex of planning, constructive, engineering, technical and organizational measures, such as smoke protection, proper fire resistance and fire propagation limits of the structures, providing and proper decoration of evacuation routes, smokeproof stairways, annunciator systems, etc. Therefore, introducing of fire safety systems in high-rise buildings is a priority task at the stage of their designing, construction, and operation.


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.


Buildings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 51
Author(s):  
Amaya Osácar ◽  
Juan Bautista Echeverria Trueba ◽  
Brian Meacham

There is a trend in Europe towards increasing the quality and performance of regulations. At the same time, regulatory failure has been observed in the area of building fire safety regulation in England and elsewhere. As a result, an analysis of the appropriateness of fire safety regulations in Spain is warranted, with the objective being to assess whether a suitable level of fire safety is currently being delivered. Three basic elements must be considered in such analysis: the legal and regulatory framework, the level of fire risk/safety of buildings that is expected and the level which actually results, and a suitable method of analysis. The focus of this paper is creating a legal and regulatory framework, in particular with respect to fire safety in buildings. Components of an ”ideal” building regulatory framework to adequately control fire risk are presented, the existing building regulatory framework is summarized, and an analysis of the gaps between the ideal and the existing systems is presented. It is concluded that the gaps between the ideal and the existing framework are significant, and that the current fire safety regulations are not appropriate for assuring delivery of the intended level of fire risk mitigation.


2014 ◽  
Vol 915-916 ◽  
pp. 356-361
Author(s):  
Zheng Wen Xie

FDS simulation software was used to establish the full size lampblack physics model of single wind pipe, using the orthogonal design method design of analog calculation conditions, research in the nozzle pressure, the droplet radius, nozzle, flow quantity and injection angle parameters under different conditions of water mist fire extinguishing effect. Based on a full-scale combustion and water mist fire extinguishing experiment, the water mist fire suppression was observed and test analysis etc, to better understand the flue water mist fire extinguishing feasibility, provides the theory basis for the design of efficient, reliable flue fire extinguishing system.


Drones ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 17
Author(s):  
Elena Ausonio ◽  
Patrizia Bagnerini ◽  
Marco Ghio

The recent huge technological development of unmanned aerial Vehicles (UAVs) can provide breakthrough means of fighting wildland fires. We propose an innovative forest firefighting system based on the use of a swarm of hundreds of UAVs able to generate a continuous flow of extinguishing liquid on the fire front, simulating the effect of rain. Automatic battery replacement and extinguishing liquid refill ensure the continuity of the action. We illustrate the validity of the approach in Mediterranean scrub first computing the critical water flow rate according to the main factors involved in the evolution of a fire, then estimating the number of linear meters of active fire front that can be extinguished depending on the number of drones available and the amount of extinguishing fluid carried. A fire propagation cellular automata model is also employed to study the evolution of the fire. Simulation results suggest that the proposed system can provide the flow of water required to fight low-intensity and limited extent fires or to support current forest firefighting techniques.


Author(s):  
Ti-Sheng HUANG ◽  
Nobuyoshi KAWABATA ◽  
Miho SEIKE ◽  
Masato HASEGAWA ◽  
Futoshi TANAKA ◽  
...  

2016 ◽  
Vol 61 (Special Issue) ◽  
pp. S26-S36 ◽  
Author(s):  
M. Žitňák ◽  
K. Kollárová ◽  
M. Macák ◽  
M. Prístavková ◽  
M. Bošanský

The objective of this work is the evaluation of threats in the field of safety, fire safety, quality and environment in the post-harvest treatment of grain, with an emphasis put on pre-cleaning and drying of grain. The paper describes the technology of pre-cleaning and drying of grain. Risks for individual machines were evaluated using a failure mode and effects analysis (FMEA), which is used to evaluate the threats in terms of fire risk, occupational safety, the effect of machine on the quality of final product, and effect on the environment. We have proposed measures and solutions to eliminate or minimise the consequences of threats. Risk rates are evaluated before and after measures adopted. It can be stated based on the results that risk was successfully reduced to an acceptable level after adopting measures.


Author(s):  
T Goode

Machinery spaces in the majority of Royal Navy (RN) vessels use carbon dioxide (CO2) as the primary fire suppressant. While CO2 is very effective for firefighting, particularly in machinery space application, it is harmful to life in the concentrations required for effective fire suppression; exposure to concentrations greater than 15% can cause death within sixty seconds. The use of CO2 and similar fire suppressant systems in machinery spaces presents a risk due to the potential exposure of personnel. This may occur in a fire scenario where personnel are unable to escape the affected compartment, if there is a leak in the system, or due to accidental discharge. These risks are typically mitigated through physical means and procedural controls. However, in the hierarchy of safety controls the primary means should always be the elimination of the hazard. Babcock Energy and Marine undertook a study for the United Kingdom Ministry of Defence (MoD) into alternative methods of firefighting on Royal Navy minor warship machinery spaces with the safety of personnel considered a key requirement. The study identified five alternatives to CO2 available on the market. One particular aerosol fire suppression system was found to be superior to the others for application in small craft. This system is not toxic, non-ozone depleting and leaves almost no residue after application to the affected space, enabling re-entry (provided that the space has been ventilated to remove the products of combustion). The study concluded that traditional methods of fire suppression should be reconsidered across all small craft due to the health and safety issues associated with CO2 and the availability of improved alternatives. This paper considers the use of traditional firefighting systems on naval vessels in light of 21st century health and safety regulations. An assessment of current fire extinguishing agents is presented followed by a case study to determine the most appropriate solution for a minor warship concept with a particular aerosol system being justified as the preferred option. The paper also considers if the same conclusions would be reached for major warships or if the difference in scale results in an alternative solution.


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