Application of the Framework for Fire Investigations in Informal Settlements to large-scale real fire events – Consideration of fire formation patterns, fire spread rates and home survivability

AbstractApproximately one billion people across the globe are living in informal settlements with a large potential fire risk. Due to the high dwelling density, a single informal settlement dwelling fire may result in a very serious fire disaster leaving thousands of people homeless. In this work, a simple physics-based theoretical model was employed to assess the critical fire separation distance between dwellings. The heat flux and ejected flame length were obtained from a full-scale dwelling tests with ISO 9705 dimension (3.6 m × 2.4 m × 2.4 m) to estimate the radiation decay coefficient of the radiation heat flux away from the open door. The ignition potential of combustible materials in adjacent dwellings are analyzed based on the critical heat flux from cone calorimeter tests. To verify the critical distance in real informal settlement fire, a parallel method using aerial photography within geographic information systems (GIS), was employed to determine the critical separation distances in four real informal settlement fires of 2014–2015 in Masiphumelele, Cape Town, South Africa. The fire-spread distances were obtained as well through the real fires. The probabilistic analysis was conducted by Weibull distribution and logistic regression, and the corresponding separation distances were given with different fire spread probabilities. From the experiments with the assumption of no interventions and open doors and windows, it was established that the heat flux would decay from around 36 kW/m2 within a distance of 1.0 m to a value smaller than 5 kW/m2 at a distance of 4.0 m. Both experiments and GIS results agree well and suggest the ignition probabilities at distances of 1.0 m, 2.0 m and 3.0 m are 97%, 52% and 5% respectively. While wind is not explicitly considered in the work, it is implicit within the GIS analyses of fire spread risk, therefore, it is reasonable to say that there is a relatively low fire spread risk at distances greater than 3 m. The distance of 1.0 m in GIS is verified to well and conservatively predict the fire spread risk in the informal settlements.

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Mechanism of fire spread on facades and the new Technical Report of EOTA “Large-scale fire performance testing of external wall cladding systems”

MATEC Web of Conferences ◽

10.1051/matecconf/20130902010 ◽

2013 ◽

Vol 9 ◽

pp. 02010 ◽

Cited By ~ 7

Author(s):

Ingolf Kotthoff ◽

Jan Riemesch-Speer

Keyword(s):

Large Scale ◽

Performance Testing ◽

Fire Spread ◽

Fire Performance ◽

External Wall ◽

Technical Report

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CFD as a tool for examining fire spread mechanisms in informal settlements: faster flashover and deflected flames

10.14264/ccc4bf8 ◽

2021 ◽

Author(s):

Samuel Stevens ◽

Mohamed Beshir ◽

David Rush

Keyword(s):

Informal Settlements ◽

Fire Spread

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Fractal properties of forest fires in Amazonia as a basis for modelling pan-tropical burnt area

Biogeosciences ◽

10.5194/bg-11-1449-2014 ◽

2014 ◽

Vol 11 (6) ◽

pp. 1449-1459 ◽

Cited By ~ 7

Author(s):

I. N. Fletcher ◽

L. E. O. C. Aragão ◽

A. Lima ◽

Y. Shimabukuro ◽

P. Friedlingstein

Keyword(s):

Forest Fires ◽

Large Scale ◽

Fire Spread ◽

Small Scale ◽

Burnt Area ◽

Active Fire ◽

Fractal Properties ◽

Dynamic Global Vegetation Models ◽

Vegetation Models ◽

Global Vegetation

Abstract. Current methods for modelling burnt area in dynamic global vegetation models (DGVMs) involve complex fire spread calculations, which rely on many inputs, including fuel characteristics, wind speed and countless parameters. They are therefore susceptible to large uncertainties through error propagation, but undeniably useful for modelling specific, small-scale burns. Using observed fractal distributions of fire scars in Brazilian Amazonia in 2005, we propose an alternative burnt area model for tropical forests, with fire counts as sole input and few parameters. This model is intended for predicting large-scale burnt area rather than looking at individual fire events. A simple parameterization of a tapered fractal distribution is calibrated at multiple spatial resolutions using a satellite-derived burnt area map. The model is capable of accurately reproducing the total area burnt (16 387 km2) and its spatial distribution. When tested pan-tropically using the MODIS MCD14ML active fire product, the model accurately predicts temporal and spatial fire trends, but the magnitude of the differences between these estimates and the GFED3.1 burnt area products varies per continent.

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Simulation and thermal imaging of the 2006 Esperanza Wildfire in southern California: application of a coupled weather–wildland fire model

International Journal of Wildland Fire ◽

10.1071/wf12194 ◽

2014 ◽

Vol 23 (6) ◽

pp. 755 ◽

Cited By ~ 16

Author(s):

Janice L. Coen ◽

Philip J. Riggan

Keyword(s):

Thermal Imaging ◽

Large Scale ◽

Transient Flow ◽

Wildland Fire ◽

Fire Spread ◽

Early Morning ◽

Fuel Load ◽

Dynamic Interactions ◽

Riverside County ◽

Layer Flow

The 2006 Esperanza Fire in Riverside County, California, was simulated with the Coupled Atmosphere–Wildland Fire Environment (CAWFE) model to examine how dynamic interactions of the atmosphere with large-scale fire spread and energy release may affect observed patterns of fire behaviour as mapped using the FireMapper thermal-imaging radiometer. CAWFE simulated the meteorological flow in and near the fire, the fire’s growth as influenced by gusty Santa Ana winds and interactions between the fire and weather through fire-induced winds during the first day of burning. The airflow was characterised by thermally stratified, two-layer flow channelled between the San Bernardino and San Jacinto mountain ranges with transient flow accelerations driving the fire in Cabazon Peak’s lee. The simulation reproduced distinguishing features of the fire including its overall direction and width, rapid spread west-south-westward across canyons, spread up canyons crossing its southern flank, splitting into two heading regions and feathering of the fire line. The simulation correctly depicted the fire’s location at the time of an early-morning incident involving firefighter fatalities. It also depicted periods of deep plume growth, but anomalously described downhill spread of the head of the fire under weak winds that was less rapid than observed. Although capturing the meteorological flow was essential to reproducing the fire’s evolution, fuel factors including fuel load appeared to play a secondary role.

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Experimental Investigations of the Burning Behaviour of Transport Package Impact Limiters and of Fire Spread Impact Onto the Cask

Volume 7: Operations, Applications, and Components ◽

10.1115/pvp2018-84714 ◽

2018 ◽

Author(s):

Marina Erenberg ◽

Claus Bletzer ◽

Martin Feldkamp ◽

André Musolff ◽

Marko Nehrig ◽

...

Keyword(s):

Large Scale ◽

Fire Test ◽

Spent Nuclear Fuel ◽

Safety Evaluation ◽

Fire Spread ◽

High Level Waste ◽

Experimental Investigations ◽

Thermal Testing ◽

Steel Sheets ◽

The Impact

Accident safe packages for the transport of spent nuclear fuel and high-level waste shall fulfil international IAEA safety requirements. Compliance is shown by consecutive mechanical and thermal testing. Additional numerical analysis are usually part of the safety evaluation. For damage protection some package designs are equipped with wood filled impact limiters encapsulated by steel sheets. The safety of these packages is established in compliance with IAEA regulations. Cumulative mechanical and fire tests are conducted to achieve safety standards and to prevent loss of containment. Mechanical reliability is proven by drop tests. Drop testing might cause significant damage of the impact limiter steel sheets and might enable sufficient oxygen supply to the impact limiter during the fire test to ignite the wood filling. The boundary conditions of the fire test are precisely described in the IAEA regulatory. During the test the impact limiter will be subjected to a 30 minute enduring fire phase. Subsequent to the fire phase any burning of the specimen has to extinguish naturally and no artificial cooling is allowed. At BAM a large-scale fire test with a real size impact limiter and a wood volume of about 3m3 was conducted to investigate the burning behaviour of wood filled impact limiters in steel sheet encapsulation. The impact limiter was equipped with extensive temperature monitoring equipment. Until today burning of such impact limiters is not sufficiently considered in transport package design and more investigation is necessary to explore the consequences of the impacting fire. The objective of the large scale test was to find out whether a self-sustaining smouldering or even a flaming fire inside the impact limiter was initiated and what impact on the cask is resulting. The amount of energy, transferred from the impact limiter into the cask is of particular importance for the safety of heavy weight packages. With the intention of heat flux quantification a new approach was made and a test bench was designed.

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Struggles to remain in Kigali’s “unplanned” settlements: the case of Bannyahe

Environment and Urbanization ◽

10.1177/0956247819886229 ◽

2019 ◽

Vol 32 (1) ◽

pp. 19-36 ◽

Cited By ~ 5

Author(s):

Shakirah Esmail ◽

Jason Corburn

Keyword(s):

Large Scale ◽

Informal Settlements ◽

Legal Regime ◽

Property Valuation ◽

Property Owners ◽

Neighbourhood Level

Examining the precarious status of informal settlements in Kigali at a time of large-scale planning-induced expropriation, this article considers urban contestation in the context of the city’s changing spatial-legal regime. We analyse the case of one informal settlement’s expropriation and relocation – the settlement of Bannyahe – and the contestation that has ensued as resident property owners take the District of Gasabo to court. Through interviews with settlement residents, we follow the fates of these displaced urban citizens and consider their struggles to remain in their homes. Finally, we suggest that such contestation over legal procedural regularity and negotiation over property valuation at the neighbourhood level forms the limit of overt opposition to the city’s masterplan. Terming these limits to contestation “silent boundaries” that circumscribe contestation for property owners in the Bannyahe settlement, we offer perspectives on contestation and compromise amidst urban socio-spatial reordering in the “new Kigali”.

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Wildland fire spread modelling using cellular automata: evolution in large-scale spatially heterogeneous environments under fire suppression tactics

International Journal of Wildland Fire ◽

10.1071/wf09119 ◽

2011 ◽

Vol 20 (5) ◽

pp. 633 ◽

Cited By ~ 27

Author(s):

A. Alexandridis ◽

L. Russo ◽

D. Vakalis ◽

G. V. Bafas ◽

C. I. Siettos

Keyword(s):

Cellular Automata ◽

Geographical Information Systems ◽

Large Scale ◽

Fire Suppression ◽

Meteorological Data ◽

Fire Spread ◽

Geographical Information ◽

Heterogeneous Environments ◽

Detailed Model ◽

Technical Specifications

We show how microscopic modelling techniques such as Cellular Automata linked with detailed geographical information systems (GIS) and meteorological data can be used to efficiently predict the evolution of fire fronts on mountainous and heterogeneous wild forest landscapes. In particular, we present a lattice-based dynamic model that includes various factors, ranging from landscape and earth statistics, attributes of vegetation and wind field data to the humidity of the fuel and the spotting transfer mechanism. We also attempt to model specific fire suppression tactics based on air tanker attacks utilising technical specifications as well as operational capabilities of the aircrafts. We use the detailed model to approximate the dynamics of a large-scale fire that broke out in a region on the west flank of the Greek National Park of Parnitha Mountain in June of 2007. The comparison between the simulation and the actual results showed that the proposed model predicts the fire-spread characteristics in an adequate manner. Finally, we discuss how such a detailed model can be exploited in order to design and develop, in a systematic way, fire risk management policies.

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Fire spread from MODIS burned area data: obtaining fire dynamics information for every single fire

International Journal of Wildland Fire ◽

10.1071/wf16003 ◽

2016 ◽

Vol 25 (12) ◽

pp. 1228 ◽

Cited By ~ 8

Author(s):

David Frantz ◽

Marion Stellmes ◽

Achim Röder ◽

Joachim Hill

Keyword(s):

Large Scale ◽

Fire Regimes ◽

Fire Spread ◽

Burned Area ◽

Large Area ◽

Fire Dynamics ◽

Seed Point ◽

Individual Object ◽

The Individual ◽

Area Data

Fire spread information on a large scale is still a missing key layer for a complete description of fire regimes. We developed a novel multilevel object-based methodology that extracts valuable information about fire dynamics from Moderate Resolution Imaging Spectroradiometer (MODIS) burned area data. Besides the large area capabilities, this approach also derives very detailed information for every single fire regarding timing and location of its ignition, as well as detailed directional multitemporal spread information. The approach is a top–down approach and a multilevel segmentation strategy is used to gradually refine the individual object membership. The multitemporal segmentation alternates between recursive seed point identification and queue-based fire tracking. The algorithm relies on only a few input parameters that control the segmentation with spatial and temporal distance thresholds. We present exemplary results that indicate the potential for further use of the derived parameters.

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