One of the most noticeable characteristics of informal settlements is their high dwelling density. Informal settlements are heavily packed, with small separation distances between dwellings being one of the main parameters responsible for the increased risk of fire spread. However, how the separation distance affects fire dynamics and fire spread mechanisms between buildings is not clear, especially for dwellings built entirely with thermally thin materials, such as corrugated steel sheets. For this reason, reduced scale experiments have been conducted to assess the influence of the presence of an adjacent obstruction and the effects of the separation distance between the fire dwelling and such obstruction on fire dynamics and fire spread in informal settlements. The experiments were conducted with two different setups in a quiescent environment. The first setup consisted of two 1/4 scale thermally thin bounded (steel clad) ISO standard rooms (dwellings), and five separation distances were tested (200, 300, 400, 500, and 600 mm). The second setup used the same compartment as the fire dwelling and a wide wall three times wider than the compartment as an obstruction, this wide wall represents a limit wall between properties or a larger dwelling; the same five separation distances were assessed. Heat release rates (HRRs), gas temperatures, radiative heat fluxes (RHFs), and wall temperatures were measured. We found that the wide wall scenarios presented a more severe fire scenario and more potential for fire spread, presenting higher HRR, hot gas temperatures, wall temperature, incident RHF at the adjacent obstruction, and adjacent obstruction wall temperatures. Additionally, lower times to flashover, and consequently earlier external flames were observed, which also contribute to the increased likelihood of fire spread.

Fire load density is fundamental to modelling compartment fire dynamics. In the context of informal settlements (IS)-residential areas which develop organically, without authorisation or regulatory oversight from the state-it represents a first step towards understanding the extent and rate of fire spread, thus characterising fire hazard and enabling development of mitigation strategies. Quantification of fire load for informal settlements is almost entirely absent from the literature. This paper presents estimates of fire load density from an ensemble of survey responses from 433 dwellings across 9 distinct settlements close to Cape Town, South Africa. Conditional on the assumption of a Gumbel distribution, fire load density was estimated between 247-947 MJ/m2 (mean) and 354-1360 MJ/m2 (80% fractile), depending on the assumed calorific value of movable furniture items and the inclusion or exclusion of non-movable combustibles. These outcomes are compared to the limited prior literature and code recommendations. The large variation in estimated fire load density highlights the requirement for greater understanding of contextual variation in fire load and modelling of fire dynamics in IS to support risk assessment for more than 1 billion people living in these settlements worldwide.

Understanding the thermo-mechanical behavior of Low-Cement Concrete (LCC) under fire is essential for its safe and durable use in structures. This study investigates cylindrical specimens (empty set100 x 200 mm) made with Ordinary Portland Cement (OPC)-CS1, 35% Fly Ash (FA)-CS2, and 50% Ground Granulated Blast Furnace Slag (GGBS)-CS3 preloaded to 30% of their 90-day compressive strength and exposed to peak temperatures of 400 degrees C and 600 degrees C, followed by cooling to 400 degrees C, 200 degrees C or ambient. Axial strain evolution was monitored using Digital Image Correlation (DIC), while residual compressive strength was measured post-exposure. Results show that CS1 exhibited the highest early-age strength and largest thermal expansion, whereas CS2 and CS3 showed slower expansion, earlier onset of contraction, and moderate peak strains. LCC mixes experienced delayed internal heating, reducing thermal gradients during fire exposure. Residual strength was highest for CS1 (77%), followed by CS3 (67%) and CS2 (63%). After heating to 600 degrees C, concretes lost on average 20-24% of their strength, while 400 degrees C exposure gave an average loss of 10-15%. Prolonged heating improved SCM concretes' retention, showing that fly ash and GGBS can limit thermal deformation while maintaining long-term strength and fire resilience.

Fires in informal settlements are a major threat to life and property, particularly in low-income urban areas. In Cape Town, South Africa, over 2,200 informal settlement fires occur annually, resulting in hundreds of fatalities and millions of Rand in losses. This paper evaluates the cost-effectiveness of fire alarm systems in Cape Town’s informal settlements using the J-value methodology, which integrates societal welfare and economic considerations. Analysis of local data found that Cape Town averages 2,210 fires, 282 deaths, and 2,970 injuries annually, across its 181,606 informal dwellings. The results show that both Lumkani’s rate-of-rise heat detector and a standard smoke alarm are highly cost-effective, with J-values of 0.247 and 0.011, respectively. The societal benefit is driven primarily by reductions in fire-related fatalities, with injury and property damage reductions contributing negligible amounts of benefit. Sensitivity and threshold analyses reveal that both systems remain justified under a wide range of assumptions, though Lumkani requires a higher, but practicable, fatality reduction to be cost-effective. The findings support investment in alarm systems for high-risk communities and highlight the need for improved data collection and real-world effectiveness studies to inform future fire safety policy and intervention design in informal settlements.

This paper applies the J value framework to assess when interlinked domestic fire alarm systems would be cost effective in Scotland and England. Pre policy national statistics pool dwellings with no alarms, standalone alarms (the vast majority), and some interlinked systems, so they do not identify the marginal effect of interlinking. We therefore present threshold (break-even) conditions: combinations of reductions in fatalities, injuries, and direct property damage that yield J ≤ 1 for self and professional installation, using historical statistics only as non-causal, illustrative anchors for sensitivity analyses. It was found that, across both countries, damage reduction is the dominant driver of cost-effectiveness, followed by fatality reduction; injury reduction has limited influence (assuming direct injury costs only). One-way thresholds indicate that achieving J≤ 1 typically requires around 30–60 J , while societal discount rates have modest effects. Interlinked systems can be cost effective where installed costs are lower (for example self-installation) and reductions in property damage, and secondarily fatalities, are moderate to large. Improved data on alarm type and performance, property-damage costs, and near-misses would enable movement from threshold analysis to causal evaluation.

Computational urban fire spread modelling techniques have scope for being utilised in fire risk quantification and for developing fire spread mitigation measures. Historically, most have been developed in the context of post-earthquake fire spread, but the numerical principles behind the fundamental mechanisms - namely fire development within, and fire spread to and from, buildings - are clearly applicable in other contexts. This paper reviews the state of the art of largescale urban fire spread modelling and discusses its applicability primarily to the relatively new context of informal settlement fires. A particular focus is given to the methods by which researchers have previously conceptualised key fire spread mechanisms. Overall, it was found that existing models provide a reasonable platform for future development. However, robust modelling will depend on better conceptualisation of key submodels, particularly the modelling of external flame and ignition by radiation and flame impingement.

In response to the challenges prevailing in the international education of fire science for graduate students, and the core one is how to accurately and efficiently disseminate cutting-edge or fundamental international knowledge in the Far East, particularly in non-English-speaking countries or regions, the State Key Laboratory of Fire Science (SKLFS) at the University of Science and Technology of China (USTC) has established an English curriculum titled Introduction of Fire Dynamics with the researchers from University of Edinburgh, UK. This course gives an effective collaborative teaching methodology that fully considers the learning/teaching characteristics of domestic and international students at USTC by combining the strengths of fire safety education across the continents and is dedicated to bridging fire safety education gaps in two hemispheres, broadening the horizons of graduate students, enhancing their professional English level and developing the critical thinking skills. It has transformed its midterm examination by incorporating experimental demonstrations and theoretical explanations of its mechanism, which significantly inspired the students' interests and passion in fire safety science, attracting extensive national official media reports from China News, People's Daily Online, China Youth Daily, etc. The students from five other Chinese universities also attended this course online, which is unusual for an English course in a non-English-speaking country, so the course was called the "hottest" course at USTC. This paper will introduce this initiative and propose important references and experiences for education innovation in fire safety science for non-native English-speaking graduate students.

Laminated glass (LG) offers superior impact resistance and reduced shard fallout compared to monolithic glass, leading to high demand in modern buildings, such as structural glass fa & ccedil;ade. However, the flammable interlayer of laminated glass poses fire risks in its application. To understand LG's thermal performance and breakage behavior, a total of 36 experiments were conducted with varying glass and Ethyl Vinyl Acetate (EVA) interlayer thicknesses under a uniform incident heat flux of 40 kW/m2. Results showed that the EVA ignited from both the unshielded edges and through cracks. A positive feedback loop between glass cracking and interlayer combustion was discovered, exacerbating the progressive failure of LG. The crack initiation points of the top radiation-exposed glass panel (Pane 1) were on the radiation-exposed surface (S1), while those on the bottom glass panel (Pane 2) were on the ambient, unexposed surface (S4). All crack initiation points appear at both the glass edge and near the borderline of the exposed and shielded areas. The breakage time of Pane 1 varied from 51 to 72 s, influenced by both the glass and interlayer thicknesses. A FE model was developed for simulating heat transfer and thermal stress, achieving a maximum temperature prediction error of 14.3 % and an average prediction error for Pane 1's breakage time of 11.2 %. Furthermore, simulation results showed that the position of critical tensile stress and three types of stress concentration zones were consistent with the crack initiation points and three crack path types observed in the experiments, providing confidence in the model's accuracy.

Informal settlements, where over 1 billion people live globally, are extremely vulnerable to fire events. Thermally thin steel-clad timber-framed homes found in South African informal settlements are a prime example of this. In this paper, we explore, through six full-scale laboratory experiments and modelling, the influence of opening locations, areas, and aspect ratios, on the fire dynamics of thermally thin and leaky compartments. It was found that having the window on the same wall as the door produced the highest heat fluxes opposite the door (13 kW/m2). Having the window opposite the door on the back wall, created a crossflow scenario which produced slightly higher fluxes opposite the door (10–11 kW/m2) compared to when the windows were on a side wall (7–9 kW/m2). Increasing the opening area by including another equally sized window, or by doubling the window width or height, slightly reduced the heat fluxes opposite the door and window, in general slightly increased the time to flashover, and significantly increased the heat release rate required for flashover. The work presented within this paper adds to the growing body of knowledge around informal settlement dwelling fire dynamics which can be used by engineers and urban planners in understanding and mitigating urban conflagrations within these communities.

More than a decade had passed since the initiation of the Syrian refugee camps in Jordan. Many gray literature documents and some academic research had been produced around Zaatari and Azraq camps. However, none of the existing research has tackled the issue of fire safety in the camps extensively, despite the noticeable fire events that occur in them.In this research, two methods are used to discuss the fire risk in the Jordanian Syrian camps of Zaatari and Azraq. The first is field assessment through visual analysis supported by observatory tours and field notes on five aspects of fire risk; ignition, fire development, fire spread within a structure, fire risk between structures, and accessibility of shelters. The second is through fire experiments on shelter materials using a cone calorimeter which aimed at seeing how the original shelter materials and the amendments that the residents make to these materials, react to fire. The results are recommendations and best practices to improve fire safety in these camps and at the same time help camp planners and shelter designers in taking more fire-conscious decisions in the future.

Simulation-based approaches for characterising the fire behaviour of travelling fires in large compartments are a potentially valuable complement to experimental studies, providing useful insights on evolving boundary conditions for structural response. They admit the possibility of carrying out systematic parametric studies decoupled from experimental uncertainties, however, sufficiently general models have not been previously demonstrated. Here, we explore the potential for “scaling-up” a “stick-by-stick” CFD model which had been carefully calibrated for the case of an isolated crib, of 2.8 m diameter, to a uniformly distributed fuel bed of extent 4.2 m × 14.0 m located within an open compartment 9 × 15 m in plan, with internal height 2.9 m. The results in terms of the fire spread and burnout predictions are very encouraging, and the heat release rate evolution is also consistent with the experimental value. Furthermore, there is a relatively good match of predicted and measured incident radiant fluxes during the fire spread on the wood cribs.Discrepancies in predicted post fire fluxes and gas phase temperatures can be attributed to the effects of wind on the fire plume (not modelled) and deficiencies in representation of heat transfer from the glowing embers. These factors are expected to have a modest impact on the prediction of fire spread on a horizontally-orientated flat fuel bed, the prime interest of the current work. Thus, the established “numerical simulator” looks to have good potential as a tool to explore and characterise the behaviour of travelling fires subject to different compartment boundary conditions.

Concrete is one of the most widely used construction materials globally. Experimental and numerical observations have revealed that failure of concrete structures may occur not only during the heating phase but also during the decay phase of a fire. With the global imperative to reduce CO2 emissions from cement production, traditional concrete is increasingly being replaced with low-cement alternatives. However, there remains a lack of experimental testing regarding the effects of additional supplementary cementitious materials in concrete during and after fire. This paper presents preliminary findings from elevated temperature compressive tests conducted on concrete with three different mixes, two of which involved 40% and 50% cement replacement. The experimental programme indicates that, regardless of the mix type, internal temperatures recorded in the cylinders were minimally affected by differing mix proportions under identical heating scenarios. Additionally, the paper explores the influence of preloading on both the magnitude of peak thermal expansion and the time to reach peak thermal expansion. It is observed that a reduction in cement content results in comparatively more rapid thermal expansion. Furthermore, during the decay phase, the contraction rates are similar regardless of preloading conditions or the reduction of cement content, for identical heating and cooling scenarios.

Approximately 1 billion people in the world still live in informal settlements with comparatively low living standards and outdated firefighting equipment. In recent years, informal settlement fires have occurred frequently and globally, however, research into informal settlement fires in the Far East remains underdeveloped. This work briefly summarizes informal settlement types and discusses their fire safety characteristics in China. It is shown that informal settlements in China include non-compliant buildings, non-standard altered buildings, non-permanent buildings, and traditional ethnic minority buildings. More relevant research is needed to promote equity of fire safety outcomes for all.

Previous full-scale fire studies revealed that the role of wind on fire spread between informal settlement dwellings was critical. However, the influence of wind conditions on informal settlement dwellings fire spread is currently understudied in the literature. This study aimed to investigate the effect of external wind conditions on fire spread between two informal settlement dwellings with a distance of 1 meter between them. A parametric numerical analysis was performed using the computational fluid dynamics code Fire Dynamics Simulator. The numerical models were benchmarked through laboratory experiments. The investigation included an analysis of the fire spread mechanism, flashover conditions, and heat transfer processes at the boundaries of the dwellings. Simulations were conducted with burning wood cribs as fuel and three wind speeds (6 m/s, 10 m/s, and 14 m/s) with four wind directions (East, West, South, and North). Results showed that wind speed and direction had a significant impact on the fire dynamics of the origin dwelling and its spread to neighboring dwellings. The wind direction also influenced the time to flashover in both dwellings, with a delay observed when the wind flowed through the alley between the two dwellings. The total heat transfer coefficient was found to be directly proportional to the wind speed for all directions. The internal radiative heat transfer coefficient of one wall was found to represent the total heat transfer coefficient in different scenarios. This study highlights the complexity of determining the role of wind in urban fire spread and underscores the need for further research in this area.

In urban or informal settlement fires, the influence of an adjacent inert wall/dwelling on the fire development of the burning dwelling is still unknown. Therefore, 41 compartment fire experiments were conducted with a 1/4 scale ISO 9705 room, with a calcium silicate board acting as the inert wall, was placed in front of the burning compartment's opening with distances between 50 and 1250 mm. Parameters such as the mass loss rate of fuel, temperatures of gas and walls, heat flux imposed on the floor, and time to flashover were analyzed. From the experiments, it was found that the flashover occurrence times differed significantly with or without the adjacent dwelling, and the time to flashover increased gradually with increasing distance from 50 to 300 mm between the burning compartment and adjacent wall, but decreased with distance from 300 to 600 mm. The heat flux to the floor was calculated and correlated well with measured values, confirming that the observed experimental phenomenon was primarily caused by the interaction between the combustion efficiency of fuel and the different heat losses from hot gas flowing out from the opening depending on the adjacent wall location. Moreover, a modified MQH method and a theoretical model were proposed to predict the gas temperature and time to flashover, respectively.

The design approaches of reinforced concrete (RC) columns are well understood at ambient temperature, and experimental test results correlate well with methods to investigate the strength capacity and failure criteria/modes of structural elements; however, this is not the case in fire scenarios.Using a meta-analysis, this study examines and evaluates the statistical reliability of six distinct methods/tabular guidelines from five countries' fire-resistant design concepts and procedures.In addition to this, the historical development of guidelines was emphasized.Meta-analysis is a method that examines a large dataset to determine the general trend of factors influencing the same object.In this investigation, 175 full-scale concrete column experiments were collected from around the world to determine their fire resistance capacity.It was discovered that all methods and tabular guidelines are founded on a specific set of experiments, and their applicability to a newly available set of experiments is beset with uncertainty.Method A of Eurocode (EN 1992(EN -1-2:2019) ) is relatively accurate in predicting the fire resistance rating (FRR) for up to 240 minutes, whereas Method B is accurate for up to 150 minutes.The Chinese method (DBJ/T 15-81) is regarded as quite effective for the set of experiments from which the Eurocode equation was derived, but the accuracy of its predictions for other sets of experiments was highly variable.The ACI 216.1 and IS 1642 methods appear to underestimate the FRR in most experiments.Therefore, it is concluded that either the limitations of these guidelines must be modified, or new equation/tabular guidelines are required in place of newly available experiment sets.

Due to socio-economic and climatic changes around the world, large outdoor fires in the built environment have become one of the global issues that threaten billions of people. The devastating effects of them are indicative of weaknesses in existing building codes and standard testing methodologies. This is due in part to our limited understanding of large outdoor fire exposures, including the ones from wildland to communities and within communities. To address this problem, the Ignition Resistance Committee (IRC) of the International Association of the Fire Safety Science working group 'Large Outdoor Fires and the Built Environment' was established. This manuscript is the result of one of the IRC's initiatives to review current knowledge on exposures associated with large outdoor fires, identify existing knowledge gaps, and provide recommendations for future research. The article consists of two sections: the wildland fire exposure to the built environment and the settlement fire exposure to structures. Each section presents a comprehensive review of experimental and numerical studies of exposure mechanisms (flame contact and convection, radiation, and firebrands). The review concludes with a discussion on data consistency and existing knowledge gaps to highlight future directions for each of the three fire exposure mechanisms.

Three full-scale experimental compartment fires are compared to investigate the effect of the fuel location and the ventilation factor on under ventilated thermally thin bounded ISO-9705 compartments. Wood cribs were used as the fuel load and the crib placement was varied between two locations (back and middle) to study the effect of the fuel location. Furthermore, the ventilation conditions were changed from a door and window (i.e., ventilation factor of 2.58 m 5/2 ) to only a door (i.e., ventilation factor of 2.26 m 5/2 ) for the scenario where the cribs were placed at the back of the compartment. The novelty of this work lies in its examination of the time to flashover, gas layer temperature, heat release rate, and external radiative heat fluxes, specifically considering the impact of fuel location and ventilation factor. It was observed that placing the fuel package in the middle of the compartment led to a longer growth phase, hotter gas layer temperature, a higher Heat Release Rate (HRR) needed for flashover ( q̇_fo ), and higher external radiative heat fluxes through openings. It was also found that, decreasing the ventilation factor decreased the heat losses and therefore the q̇_fo . Decreased ventilation also affected the height of the neutral plane, as one would expect, and the shape of the external plume, but did not have significant effect on the temperature within the compartment, the walls of the compartment, and the external radiative heat flux.