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China, one of the most populous countries in the world, has suffered the highest number of natural disaster-related deaths from fire. On local scales, the main causes of urban fires are anthropogenic in nature. Yet, on regional to national scales, little is known about the indicators of large-scale co-varying urban fire activity in China. Here, we present the China Fire History Atlas (CFHA), which is based on 19 947 documentary records and represents fires in urban areas of China over the twentieth century (1901-1994). We found that temperature variability is a key indicator of urban fire activity in China, with warmer temperatures being correlated with more urban fires, and that this fire-temperature relationship is seasonally and regionally explicit. In the early twentieth century, however, the fire-temperature relationship was overruled by war-related fires in large urban areas. We further used the fire-temperature relationship and multiple emissions scenarios to project fire activity across China into the twenty-first century. Our projections show a distinct increase in future urban fire activity and fire-related economic loss. Our findings provide insights into fire-climate relationships in China for densely-populated areas and on policy-relevant time scales and they contribute spatial coverage to efforts to improve global fire models.

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A simple laboratory-scale experimental method was developed to study firebrand generation processes. As part of these experiments, Japanese wind facilities were used to elucidate the effect of wind speed on firebrand generation from structural materials. It was found that very simple experimental methodologies developed as part of this study for mock-ups of full-scale roofing assemblies yielded important understanding into firebrand generation processes for both real-scale structure combustion processes as well as available firebrand information from urban and wildland-urban interface (WUI) fires.

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A shared feature in the rapid spread of large outdoor fires are the production or generation of new, far smaller combustible fragments from the original fire source referred to as firebrands. A simplified experimental protocol has been developed that allows for the study of firebrand generation processes from various structural materials exposed to an applied wind field. The influence of angle of orientation on the firebrand production process is investigated. The thickest firebrands were produced with experiments with 45° angle under 8 m/s. The influence of angle was found to have the same trend under the tested wind speeds and to be more apparent at 8 m/s than 6 m/s. As installation angles are a key factor for photovoltaic panel (PV) efficiency, often only the solar energy efficiency is considered in PV panel orientation decisions. Yet, this study demonstrates that the types of firebrands generated in the event of large outdoor fires were sensitive to the angle of installation for structural materials used as surrogates for PV panels. The work is unique in that is begins the discussion on firebrand production from cutting edge home technologies, such as PV panels. These results have implications for how installation angles may influence firebrand production in the event of large outdoor fire outbreaks.

RESUMEN

Fire spread occurs via radiation, flame contact, and firebrands. While firebrand showers are known to be a cause of spot fires which ignite fuels far from the main fire front, in the case of short distance spot fires, radiation from the main fire may play a role for firebrand induced ignition processes. Many past investigations have focused on singular effects on fire spread, and little is known about coupled effects. The coupled effect of radiative heat flux and firebrand showers on ignition processes of fuel beds is studied by using a newly developed experimental protocol. The newly developed protocol includes the addition of a radiant panel to the existing experimental setup of a firebrand generator coupled to a wind facility. Experiments were performed under an applied wind field, as the wind is a key parameter in large outdoor fire spread processes. Results show that radiant heat flux plays an important role for ignition by firebrands under 6 m/s while little effect was observed under 8 m/s.

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Firebrands are produced from combustion of both vegetative and structural fuels in large outdoor fires. It is well known that firebrand generation, transport, and ignition mechanisms result in rapid and potentially devastating fire spread processes in large outdoor fires. In this article, the basic mechanisms of firebrand generation, transport, and ignition are discussed with an emphasis on how fundamental combustion knowledge may play an important role in this complex problem.

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Firebrands generated from structures are known to be a source of rapid flame spread within communities in large outdoor fires, such as wildland-urban (WUI) fires, and urban fires. It is important to better understand firebrand generation mechanism to prevent structure ignitions by firebrands. Though the wind plays an important role during the large outdoor fires, little known is the influence of wind speeds on firebrand production. To this end, a series of experiments were performed using mock-ups of full-scale wall assemblies exposed to wind. The objective of this study was to examine if experiments with mock-ups of full-scale wall assemblies may provide insight into firebrand generation from structures. Specifically, generated firebrands were collected and compared with those collected from full-scale components and a full-scale structure. The relationship between projected area and mass of firebrands were compared with previous experimental data. It was found that the projected area of firebrands was proportional to the firebrand mass in this study, which is the same as those from experimental studies performed for full-scale components and a full-scale structure. The slope of the relationship of the projected area and the mass of firebrands was the same under the same wind speed and was affected by the applied wind speed within this experimental range.

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Large outdoor fires present a risk to the built environment. Examples often in the international media reports are wildfires that spread into communities, referred to as Wildland-Urban Interface (WUI) fires. Other examples are large urban fires including those that have occurred after earthquakes. Firebrands are a key mechanism on how rapidly fires spread in urban fires and WUI fires. An experimental protocol has been developed to ignite full-scale roofing assemblies and quantify the degree of firebrand production during the combustion process. As wind is an important factor in firebrand generation, the experiments were conducted under a range of wind speeds at the Building Research Institute's (BRI) Fire Research Wind Tunnel Facility (FRWTF). A further unique aspect of this work is the experimental results are compared to firebrand size and mass distributions collected from an actual large-scale urban fire in Japan. Results of these experiments demonstrate that when only oriented strand board (OSB) is applied as sheathing, a significant number of firebrands collected from roofing assemblies were less than 1 g and 10 cm2. It was also observed that experiments on individual building component firebrand generation provided useful insights into actual urban fire firebrand generation.

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It is well accepted that as structures are exposed to wind, stagnation planes are produced around structures. Past work by the authors demonstrated for the first-time that wind-driven firebrand showers may accumulate in these stagnation planes. While those experiments demonstrated this important phenomenon, due to the limited duration of firebrand showers of the original NIST Batch-Feed Firebrand Generator, it was not possible to perform a more systematic study. To this end, a series of detailed experiments were performed using the recently developed NIST Continuous-Feed Firebrand Generator capable of firebrand showers of unlimited duration. Full-scale walls of varying size were placed downstream of the device and the wind speed was varied in increments up to 10 m/s. The experiments were conducted in the Building Research Institute's Fire Research Wind Tunnel Facility (FRWTF). For a given wall size exposed to specific firebrand size/mass distribution, it was observed that wind speed influences not only the spatial location and extent of the accumulated firebrands in the stagnation plane in front of the wall, but also the nature of the smoldering combustion intensity of the accumulated firebrands. The experiments demonstrated that higher wind speeds (10 m/s) did not promote accumulation of firebrands in stagnation planes in front of walls. The data may be used to provide guidance to appropriate separation distances that combustibles should be placed near structures and is also of great use to develop and validate numerical models of firebrand accumulation.

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Firebrands are a significant source leading to structures ignited and lost in large outdoor fires, such as Wildland-Urban Interface (WUI) fires, a large international problem, and urban fires, common in Japan. Sadly, hardly any information is available with regard to firebrand production from burning structures or actual large outdoor fires in general. To this end, an experimental database is being generated from firebrand generation from structure combustion. This paper will focus on how these detailed database results are being used to generate firebrand showers using a redesigned firebrand generator experimental apparatus installed in a full-scale wind tunnel, with the intent to experimentally simulate firebrand showers produced from structure combustion in large outdoor fires.

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Purpose: To evaluate the acute impact of the wildfire smoke episode in 2008 on the ocular surface of subjects living in the Metropolitan Area of Buenos Aires (MABA). Methods: A total of 86 subjects were evaluated: Group 1 comprised patients from a public ophthalmology hospital (N=35) and Group 2 comprised healthy volunteers (N=51). All subjects answered a questionnaire on ocular symptoms and underwent ophthalmologic examination [bulbar conjunctival hyperemia, corneal fluorescein staining, rose bengal vital staining, tear break-up time (TBUT), Schirmer I test, tear lysozyme, and impression cytology] during and after the acute episode. Concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), and particulate matter (PM) were measured before, during, and after the acute episode. Results: Both groups showed a statically significant increase in ocular symptoms and bulbar conjunctival hyperemia and a statically significant decrease in tear break-up time during the acute episode. Group 1 showed more severe symptoms and a statistically significant increase in fluorescein and rose bengal staining intensities during the acute episode. We found a significant negative correlation between ocular symptoms and tear break-up time. During the episode, the levels of CO, NO2, and particulate matter in MABA were four times higher than the usual average levels for the same period in 2007 and 2009. Conclusions: Increased air pollution from the burning of biomass is associated with a decrease in the stability of the tear film (TBUT), generating areas of ocular surface exposure that may be the cause of the increased feeling of irritation. Group 1 was more affected by not having a healthy ocular surface, and thus consulted an ophthalmologist. Cytological changes in the conjunctiva were not observed, which could be due to the short duration of the episode. .

Objetivo: Avaliar os efeitos agudos da fumaça do episódio de incêndio violento ocorrido em 2008, sobre a superfície ocular de sujeitos que vivem na Região Metropolitana de Buenos Aires (MABA). Métodos: Um total de 86 indivíduos foram avaliados: Grupo 1: pacientes de um hospital público de oftalmologia (N=35) e Grupo 2: voluntários saudáveis (N=51). Todos os participantes responderam a um questionário sobre os sintomas oculares e foram submetidos a exame oftalmológico (hiperemia conjuntival bulbar, teste de fluoresceína, corante rosa bengala, tempo de ruptura do filme lacrimal (TBUT), teste de Schirmer I, lisozima lacrimal e citologia de impressão) durante e após o episódio agudo. As concentrações de monóxido de carbono, dióxido de nitrogênio e partículas (PM) foram medidas antes, durante e após o episódio agudo. Resultados: Ambos os grupos apresentaram aumento estatisticamente significativo dos sintomas oculares, hiperemia conjuntival bulbar, e diminuição estatisticamente significativa no tempo de ruptura do filme lacrimal durante o episódio agudo. Grupo 1 apresentou maior intensidade dos sintomas e aumento estatisticamente significativo no teste de fluoresceína e rosa bengala durante o episódio agudo. Encontramos uma correlação negativa significativa entre os sintomas oculares e tempo de ruptura do filme lacrimal. Durante o episódio agudo de 2008, os níveis de CO, NO2 e PM na Região Metropolitana de Buenos Aires foram 4 vezes maiores do que os níveis médios habituais para o mesmo período de 2007 e 2009. Conclusões: O aumento da poluição do ar a partir da queima de biomassa está associado a uma diminuição da estabilidade do filme lacrimal (TBUT) gerando zonas da exposição da superfície ocular, que podem ser a causa do aumento da sensação de irritação. Grupo 1 foi mais afetado por não ter superfície ocular saudável e, portanto, consultaram um oftalmologista. Mudanças citológicas da conjuntiva não foram observadas e isso poderia ser devido ...

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RESUMEN

Em janeiro de 2013, uma catástrofe ocorrida em Santa Maria (RS), decorrente de um incêndio em ambiente fechado, resultou em 242 mortes, a maioria por lesões inalatórias. Em novembro de 2013, quatro vítimas necessitaram de suporte intensivo após inalação de fumaça em incêndio no Memorial da América Latina, em São Paulo (SP). Este artigo relata a evolução clínica e o manejo dos pacientes com lesão inalatória vítimas de uma catástrofe. Os pacientes ERL e OC apresentaram insuficiência respiratória precoce com broncoaspiração de material carbonáceo e intoxicação por monóxido de carbono. Foi instituído suporte ventilatório com oxigênio a 100%, retirada do material aspirado por broncoscopia, e terapia empírica com nitrito de sódio e tiossulfato de sódio para intoxicação por cianeto. O paciente RP apresentou tosse e queimação retroesternal. Evoluiu com insuficiência respiratória por edema de via aérea alta e infecção pulmonar precoce, manejados com ventilação pulmonar protetora e antimicrobianos. Foi extubado após melhora do edema no seguimento broncoscópico. O paciente MA, asmático, apresentou intoxicação por monóxido de carbono e broncoespasmo, sendo tratado com hiperóxia normobárica, broncodilatadores e corticoterapia. A estadia na unidade de terapia intensiva variou de 4 e 10 dias, e todos os pacientes apresentaram boa recuperação funcional no seguimento. Em conclusão, nos incêndios em ambientes fechados, as lesões inalatórias têm papel preponderante. O suporte ventilatório invasivo não deve ser postergado em caso de edema significativo de via aérea. A hiperóxia deve ser instituída precocemente como terapêutica para intoxicação por monóxido de carbono, bem como terapia farmacológica empírica para intoxicação por cianeto em caso de suspeita.

On January 2013, a disaster at Santa Maria (RS) due to a fire in a confined space caused 242 deaths, most of them by inhalation injury. On November 2013, four individuals required intensive care following smoke inhalation from a fire at the Memorial da América Latina in São Paulo (SP). The present article reports the clinical progression and management of disaster victims presenting with inhalation injury. Patients ERL and OC exhibited early respiratory failure, bronchial aspiration of carbonaceous material, and carbon monoxide poisoning. Ventilation support was performed with 100% oxygen, the aspirated material was removed by bronchoscopy, and cyanide poisoning was empirically treated with sodium nitrite and sodium thiosulfate. Patient RP initially exhibited cough and retrosternal burning and subsequently progressed to respiratory failure due to upper airway swelling and early-onset pulmonary infection, which were treated with protective ventilation and antimicrobial agents. This patient was extubated following improvement of edema on bronchoscopy. Patient MA, an asthmatic, exhibited carbon monoxide poisoning and bronchospasm and was treated with normobaric hyperoxia, bronchodilators, and corticosteroids. The length of stay in the intensive care unit varied from four to 10 days, and all four patients exhibited satisfactory functional recovery. To conclude, inhalation injury has a preponderant role in fires in confined spaces. Invasive ventilation should not be delayed in cases with significant airway swelling. Hyperoxia should be induced early as a therapeutic means against carbon monoxide poisoning, in addition to empiric pharmacological treatment in suspected cases of cyanide poisoning.

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