Fire losses in selected property classifications of non‐residential,commercial and residential wood buildings. Part 1: hotels/motels and care homes for aged

In an attempt to evaluate the adequacy of building code requirements for selected classifications of non‐residential, commercial and residential wood buildings, researchers at Forintek Canada Corp. have examined Canadian and American fire loss statistics and compared fire losses for the selected classifications of wood buildings with those for similar buildings of non‐combustible construction. They have also examined causal factors associated with fires in those structures, extent of flame and smoke spread, ability of sprinkler systems and building construction to minimize fire losses, and outcomes of fire events. Because of the volume of information that was analysed, the results are being reported through three separate papers. This, the first, presents the ‘big picture’ with respect to fire losses in the selected classifications of non‐residential, commercial and residential structures, and discusses in detail fire losses for hotel/motel properties and care homes for the aged. Copyright © 2006 John Wiley & Sons, Ltd.     

Statistics of fires in dwellings involving textiles in the United Kingdom

There is widespread concern at present about the fire risk form the use of modern materials in upholstery and other domestic articles. One of the main characteristics of fires in dwellings which start with the ignition of textiles or furniture is that they have a high casualty rate compared with other kinds of domestic fires. Most of the casualties form such fires occur in fires which start in upholstery or bedding, often accidentally ignited by smokers' materials. Asphyxiations by smoke is the commonest cause of death in ‘textile’ and ‘upholstery’ fires. This paper presents relevant statistical information on fires in dwellings attended by local authority fire brigades which result from the ignition of upholstery, bedding, other textiles or furniture and the casualties which these fires cause.     

Highway vehicle fire data based on the experiences of US fire departments

In 2003–2007, US fire departments responded to an average of 267 600 highway vehicle fires per year. These fires caused an average of 441 civilian deaths, 1326 civilian injuries, and $1.0bn (in US dollars) in direct property damage annually. Highway vehicles include cars, trucks, and other vehicles designed for highway use; highway vehicle fires can occur anywhere, not just on a highway. While these fires and associated losses have been falling in recent years, highway vehicles fires accounted for 17% of reported US fires, 12% of US fire deaths, 8% of US civilian fire injuries, and 9% of the direct property damage from reported fires. Data from the US Fire Administration's National Fire Incident Reporting System and the National Fire Protection Association's fire department survey were used to provide details about the circumstances of highway vehicle fires. Mechanical or electrical failures caused roughly three‐quarters of the highway vehicle fires but only 11% of the deaths. Collisions and overturns were factors contributing to the ignition in only 3% of the fires, but fires resulting from these incidents caused 58% of these vehicle fire deaths. The rate of bus fires per billion miles driven was 3.5 times that for highway vehicle fires overall. Copyright © 2012 John Wiley & Sons, Ltd.     

Human survivability in motor vehicle fires

Automobile fires are consistently among the largest causes of fire death in the United States (about 500 annually) and the U.S. motor vehicle industry and others have spent a significant amount of money in recent years studying this problem. The authors of this review have analyzed the auto industry reports, the scientific literature, and statistical data, and conclude that measures should be taken to improve survivability in automobile fires. The U.S. Federal Motor Vehicle Safety Standard 302 (FMVSS 302) was introduced almost 40 years ago to measure the flammability of interior materials, but improvements in the crashworthiness of automobiles and their fuel tanks and the increased use of combustible materials have changed the motor vehicle fire scenario significantly. In particular, the primary threat has changed from ignition of a small quantity of combustible interior materials by a lit cigarette, in 1960, to ignition of a large quantity of combustible interior and exterior materials by an impact‐induced fire, at present. The authors therefore suggest that FMVSS 302 is no longer relevant to automobile fire safety and recommend improved standards based on objective criteria for fire safety performance (fireworthiness) at the system/vehicle level as is routinely done for crashworthiness. Copyright © 2008 John Wiley & Sons, Ltd.     

Study on causes of the fires in rubble piles produced after the Great East Japan Earthquake, 2011

This paper seeks to determine the trigger of faint heat generation, which was one of the causes of fires in the piles of rubble produced after the 2011 Great East Japan Earthquake. The rubble piles consist of various combustible materials, such as wood, paper and plastics, as well as non‐combustible materials from destroyed buildings. Multiple rubble outdoor storage areas were temporarily set up in the disaster areas to dispose of rubble after it was piled up and separated. However, fires have been occurring in these storage areas since the summer of 2011. One cause of such fires is thought to be the heat generated by fermentation of microorganisms that easily proliferates within the piled up rubble, ultimately resulting in spontaneous ignition. In this study, we collected samples from rubble outdoor storage areas where fires have occurred. We then conducted thermal analyses to obtain basic data, and finally, we developed safety measures to prevent the recurrence of fire. The results revealed that the heat generated during fermentation of rotten tatami and wood chips most likely acts as a trigger causing the fires, given the adiabatic conditions are good. Copyright © 2014 John Wiley & Sons, Ltd.     

Soft furnishing fires: They're still a problem

Home fires in which soft furnishings were first ignited or contributed to fire spread cause a disproportionate share of US home fire deaths. Although the death toll from these fires is much lower than in the 1980s, the rate of death per 1000 reported fires has doubled. Data from the National Fire Incident Reporting System and the National Fire Protection Association's annual Fire Experience Survey were used to create national estimates of these fires and casualties. Including both fires in which upholstered furniture was the item first ignited and contributed most to fire spread, in 2013‐2017, upholstered furniture was involved in an estimated average of 7120 (2%) home fires per year, resulting in an average of 570 (22%) deaths per year. Mattresses or bedding were involved in estimated average of 10 530 (3%) home fires per year, resulting in an average of 370 (14%) deaths annually. In most of these fires and deaths, the item was first ignited. Smoking materials were the leading cause of these fires (20%‐26%) and associated deaths (52%‐54%). Various types of operating equipment and small open flames also play a role. Understanding the causes of these fires is essential to develop new strategies to prevent them.     

Estimating the impact of the mattress fire safety Standard 16 CFR Part 1633 on bed fire outcomes

Beds are a prevalent combustible in fatal fires in the United States effective 1 July 2007, the US Consumer Product Safety Commission promulgated a standard to severely reduce the heat release rate and the early heat output from mattresses and foundations when ignited by a flaming ignition source. This study estimates the Standard's success over its first decade using fire incidence, US population, and mattress sales data. The technique mitigates the influence of some exogenous factors that might have changed during this decade. The Standard is accomplishing its purpose, preventing approximately 65 fatalities (out of an estimated 95 fatalities in 2002‐2005) from bed fires annually during 2015‐2016, although not all pre‐Standard mattresses had yet been replaced. Compared to residential upholstered furniture fires, which were not affected by the Standard, the numbers of bed fires decreased by 12%, injuries by 34%, and deaths by 82% between 2005‐2006 and 2015‐2016. Per bed fire, injuries decreased by 25% and fatalities decreased by 67%, indicating that the severity of bed fires is being reduced.     

Performance evaluation of bromofluoropropene in extinguishing liquid fuel spray fires

Liquid fuel spray fires emit high radiation heat fluxes, posing great threat to humans. The study of suitable agents and techniques for extinguishing this particular type of fire is of great importance. In this study, degradable 2‐bromo‐3,3,3‐trifluoropropene (BTP), a new clean fire extinguishing agent, was tested for its effectiveness in extinguishing three types of liquid fuel spray fires, namely diesel, gasoline, and ethanol. Bench‐scale experiments were conducted in a 6 × 5 × 3 m compartment with natural ventilation. The liquid fuels sprayed at varying pressures were ignited by a small open flame and then extinguished by a portable BTP extinguisher. Results showed that BTP of less than 60.0 g could extinguish all liquid fuel spray fires of 0.20 to 1.0 MPa in less than 2.0 s. The results also showed that when compared with fire sparked by gasoline and diesel, it is significantly easier to put out ethanol spray fires because of its high flame temperature and low flame power. Based on well‐established fire suppression theories and experimental results, the detailed mechanism of how BTP functions as an extinguishing agent in the suppression of liquid fuel spray fires will be discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

Characterization of the fire environments in central offices of the telecommunications industry

Eight free burning and two sprinklered fire tests were performed with electrical cable trays and live digital switch racks in a large enclosure to simulate telecommunications central office (TCO) fires started by electrical overheating. Very‐slow‐growing (non‐flaming), slower‐growing (partially flaming) and low‐intensity‐faster‐growing (flaming) fires releasing gray‐white, gray, and black smoke, respectively, were observed in the tests. Under quiescent conditions present in the unvented enclosure fire tests for cables, very‐slow‐growing fires were detected in about 1452 s, whereas the slower‐growing fires were detected in about 222 s by commercial fire detectors. Under ventilation conditions typical of TCOs, detection times were very similar for the five types of commercial TCOs fire detectors used in the tests. The average detection times for slower‐growing fires (cable fires) and low‐intensity‐faster‐growing fires (digital switch rack fires) were 242±17% and 249±11%s respectively. The TCO procedures to reduce smoke damage from fires (on fire detection, inlet ventilation flow is turned off and exhaust flow is turned on) were found to be beneficial. The extent of smoke damage decreased significantly with an increase in the exhaust flow rate. The chloride ion mass deposition suggested that equipment recovery would be possible in the smoke environment if the cable vapor concentration could be reduced below about 3 g/m³. The metal corrosion rate was found proportional to the 0.6th power of the smoke concentration, similar to that found for the corrosion of metal surfaces exposed to aqueous solutions of HCl and HNO₃ and for acid rain with no protective layer at the surface. Sprinkler water was found to wash down the smoke deposits on the surfaces with little indication of corrosion enhancement. Copyright © 2003 John Wiley & Sons, Ltd.     

Fire calorimetry relying on the use of the fire propagation apparatus. Part II: burning characteristics of selected chemical substances under fuel rich conditions

The paper focuses on the detailed characterization of ventilation controlled fires of industrial products that are likely to govern accidental fire scenarios in fire resistant enclosures. Results regarding under‐ventilated fires of substances that are not polymers are presented to illustrate the capability of the fire propagation apparatus (FPA) to qualify such types of fires. Based on results from heptane fire tests in both well‐ and under‐ventilated fire conditions, a set of recommendations was previously provided in order to check the validity of the experimental results. The application of these recommendations is illustrated for the selected liquid substances containing hetero‐atoms. It emerges that the fire propagation apparatus assesses quite easily the performance of well‐controlled fires in both well‐ and under‐ventilated conditions. Another major outcome of our work is that the potential of the FPA has the capability to address fire issues outside the conventional use of the equipment, in particular to qualify the burning behaviour of chemicals on the full spectrum of ventilation conditions. Copyright © 2005 John Wiley & Sons, Ltd.     

Predicting the thermal response of timber structures in natural fires using computational ‘heat of hydration’ principles

The thermo‐physical response of timber structures in fire is complex. For this reason, debate still exists today as to the best approaches for simulating thermal response in fire using tools such as finite element analysis (FEA) modelling. Much of the debate is concerned with the thermal properties of timber, for example, conductivity, specific heat and density, at elevated temperature and how such properties should be implemented or interpreted in numerical calculations. For practitioners intending to use modelling as a fire design tool for timber buildings, guidance exists on the thermal properties of softwood in Annex B of EN 1995‐1‐2. These properties are limited for use under standard fire exposure conditions because of the way in which they were derived from calibration against focussed test data. As a result, they cannot be applied to non‐standard fires, which are more representative of real fires due to a combination of varying heating rates and the decay phase of fire development. The limitations of the standard fire test (and associated curve) are widely understood. As a result, much recent structures in fire research has focussed on the ‘performance based design’ of buildings subject to increasingly realistic fire conditions. Such an approach allows engineers to quantify the level of safety that can be achieved in a building should a fire occur. In addition, the design of buildings to withstand fires proportionate to the risks foreseen and also the geometry present results in better value buildings that are inherently more robust. For the same approaches and associated benefits to be realised for timber buildings, then a number of barriers must be overcome. The most obvious of these is engineers' ability to determine timber structure temperatures as a result of fires other than the standard fire curve. This however presents a number of challenges. Upon heating, the moisture bound within begins to evaporate, volatiles begin to flow from the heated surface and char forms. The rate of which these behaviours occur and the nature of the char that forms depends on a number of factors, but most notably the rate of heating. Upon cooling, the timber member continues to generate heat energy as the surface oxidises. As a result, any models intended to simulate temperature development must consider the relationship not only between temperature and thermo‐physical characteristics but also between heating rate and the process of heat generation. Many models have been developed for this purpose; however, they are extremely complex and are some way from being ready for implementation as design tools. This paper proposes implementing ‘heat of hydration’ routines, intended for the curing of concrete structures, to simulate the heating and cooling process in timber structures. Such routines are available in many commercial FEA software packages. The adoption of the hydration routines allows the heat generation process, as a result of oxidation, to be considered in parallel with solid phase heat transfer using apparent thermal properties. The approach is shown to be very effective in simulating temperature development in timber members subject to parametric design fires. The models developed are benchmarked against experiments conducted in the 1990s by SP Trätek. Predictably, a number of the heat generation parameters adopted are shown to depend on the fire dynamics considered. However, recommended parameters are given that provide an acceptable level of accuracy for most design purposes. Copyright © 2012 John Wiley & Sons, Ltd.     

Dangers relating to fires in carbon‐fibre based composite material

Inhalable carbon fibres have been suspected to pose similar threats to human health as asbestos fibres. It is well‐known that fibres having a diameter of less than 3 µm might be inhaled and transported deep into the human respiratory system. Some composite materials use carbon fibres as structural reinforcement. These fibres do not pose any risks as such as they are firmly connected to the laminate and surrounded by a polymer matrix. Also, these fibres typically have diameters >6 µm and thus, are not inhalable. However, if the material is exposed to a fire, the carbon material might be oxidized and fractionated and thereby, inhalable fibres might be generated into the fire smoke. The capability of carbon fibre‐based composite material to produce dangerous inhalable fibres from different combustion scenarios has been investigated. It was found that the risk of fires generating inhalable carbon fibres is related to the surface temperature, the oxygen level and the airflow field close to the material surface. The temperatures necessary for oxidation of the carbon fibre is so high that it is possible that only a flashover situation will pose any real danger. Other possible danger scenarios are highly intense fires (e.g. a liquid fuel fire), or situations where structural damage is part of the fire scenario. Copyright © 2005 John Wiley & Sons, Ltd.     

Experimental study on tire fire penetration into a motorcoach passenger compartment

Two full‐scale fire experiments were conducted to determine the mode of penetration of a tire fire into the passenger compartment of a motorcoach. A special burner was designed to imitate the frictional heating of hub and wheel metal caused by failed axle bearings, locked brakes, or dragged blown tires. For the first experiment, heating to obtain tire ignition was initiated on the exterior of the passenger side tag axle wheel and for the second, on the exterior of the passenger side drive axle wheel. Measurements of interior and exterior temperatures, interior heat flux, and heat release rate were performed. Standard and infrared videos and still photographs were recorded. Both experiments showed that the tire fires ignited the plastic fender and glass‐reinforced plastic exterior side panel (below the windows) upon which the fires spread quickly and penetrated the passenger compartment by breaking the windows. Measurements showed that other potential fire penetration routes (flooring and lavatory) lagged far behind the windows in heating and degradation. Copyright © 2012 John Wiley & Sons, Ltd.     

Influence of modern plastic furniture on the fire development in fires in homes: large‐scale fire tests in living rooms

About 80% of all fire fatalities in Germany occur because of fires in homes. It has been known for some time that modern materials (synonym for materials consisting mostly of synthetic polymers) tend to burn differently from older materials (synonym for materials consisting mostly of fibrous cellulosic substances) and it has been acknowledged that the amount of combustible plastics in homes has increased significantly over the last decades. To investigate the influence of modern furniture and ventilation conditions of fires in homes, a series of four large‐scale tests in two living rooms (LRs) with adjacent rooms (ARs) was performed by BAM and the Frankfurt fire service. Two LRs, one with older furniture and one with modern furniture, were tested twice each. Each test started with the ignition of a paper cushion on an upholstered chair. The influence of modern materials on the fire development was investigated, as well as the influence of the ventilation on the fire development. In all settings, an upholstered chair was the first burning item. Results of the test series show that fires in rooms with modern furniture develop faster than fires in rooms with older furniture. This is true for temperature development in the rooms as well as for smoke production.     

Experimental study on heat release rate measurement in tunnel fires

Knowledge about the heat release rate (HRR) is essential for studying tunnel fires. The standard method in ISO 9705 is widely applied to calculate the HRR of combustion by measuring the consumption of oxygen in a fire. However, the studies of HRR measurement in full‐scale tunnel fires are rare because of the complication and costs of large experiments. This paper presents a system based on the principle of oxygen consumption calorimetry for the measurement of HRR and total heat release (THR) of full‐scale fires in tunnels. A total of 22 fire experiments are performed in a large‐scale ventilated testing metro tunnel with dimension of 100.0 m × 5.5 m × 5.5 m to validate the reliability and effectiveness of this system. Firstly, four oil spray fire tests are conducted with nozzle flow of 106 L/h at (1 ± 0.1) MW HRR to calibrate the instrumentation. Then, 18 full‐scale fire tests using square diesel pools at five sizes (0.5, 1.0, 2.5, and 5.0 m²) and wood cribs as fire sources are carried out for the measurement of HRR and THR. Results provided by the comparison between the measured HRR and THR values of the fire tests and the theoretically calculated ones show that our system works effectively in the HRR measurement of full‐scale fires in tunnels.     

The fire safety of TV set enclosure materials,a survey of European statistics

The composition of enclosure materials used in many TV sets sold on the European market has changed significantly since the early 1990s. To determine the potential impact of this change on TV fire safety, a review of European and US TV set fire statistics has been carried out. TV set fires can have internal electrical causes due to faults not apparent at the time of manufacture, simple wear and tear, or a variety of external causes. Recent detailed statistics suggest that about one third of all TV fires are due to external ignition. Available data show that the significant drop in the rate of TV set fires experienced in Europe during the 1980s is not continuing today. In fact, the rate appears to be increasing in some countries, such as the UK and Sweden. The number of TV set fires in Europe is estimated as 100 fires per million TV sets per year due to internal ignition sources, at least an order of magnitude higher than in the USA where the fire safety classifications for TV set enclosure materials has been historically high. TV set fires have a dramatic impact on life and property. To avoid an increase in TV set fires, fire safety requirements should be increased, and public awareness of the importance of fire safety in TVs heightened. Copyright © 2000 John Wiley & Sons, Ltd.     

Post-collision fires in road vehicles between 2002 and 2015

The loss of human lives and body injuries due to post-crash fires, either by smoke inhalation or due to burn injuries, are unfortunately not uncommon. The literature indicates that fire events related to crashes are still a significant problem. The increased combustible load in newer vehicles is an important factor to be taken into account for the fire safety, as well as their potential to release toxic fumes while burning. Trends indicate that the survivable collision energy will continue to increase, and, at the same time, the probability of post-crash fires rises with the collision energy. This means that the occupants of a vehicle may probably survive a high-energy collision but might sustain severe injuries or death due to a post-collision fire. This work reports a literature and interview study about post-crash fires including statistics on the causes and dynamics of post-crash fires in road vehicles based on the literature, crash and incident reports, as well as on interviews with medicine specialists. Results from this study indicate that fires in vehicles which originated by a collision event are a problem that remains to be solved.     

Heat release rate in fires

In this paper the definition of heat release rate in fires is given in terms of heat of combustion and mass loss rate of the fuel. Various components of the heat of combustion are defined. The dependency of heat of combustion components and mass loss rate on factors such as fire stages, oxygen to fuel ratio, heat flux received by the fuel, chemical composition of the fuel vapors and products are enumerated. Applications of heat release rate data for relative fire hazard of fuels, for various fire conditions, for human escape potential from fires and for the operation of fire-sensing devices are discussed.     

Fire fatality study

Over a six-year period, 530 fire fatalities resulting from 398 fires were studied in the State of Maryland. The study had two major objectives: (1) to determine the specific cause of death by a detailed autopsy stud of fire victims, and (2) to determine the specific cause of fatality-producing fire by an on-the-scene fire investigation. The fire fatality study was limited to residential fires and to fatalities that occurred within 6 h of the fire. The results of the toxicological analysis show that (1) 60% of the victims had a carboxyhemoglobin value greater than or equal to 50% carbon monoxide saturation, (2) an additional 20% had elevated carboxyhemoglobin with preexisting cardiovascular disease, (3) 11% of the victims had severe burns, (4) 9% were unexplained and (5) 40% of the victims had positive blood alcohol levels with 30% of these meeting the legal definition of intoxication (blood alcohol ≥0.1%). The fire investigations confirmed that the predominant fatal scenario is the cigarette ignition of upholstered furniture or bedding. This scenario accounted for 47% of the fires and 44% of the victims. Alcohol also appears to be significant factor in this scenario.     

Effectiveness of pre‐applied wetting agents in prevention of wildland urban interface fires

The purpose of the work described in this paper is to investigate the effectiveness of pre‐wetting structures, dead fuels, and landscaping plants in preventing fire spread from wildland fires to structures. Critical fluxes for fire growth were determined using intermediate‐scale testing for three wetting agents (water, type A foam, and gel) applied to 10 landscaping plants conditioned to 20% moisture, a mulch material, and four external structural materials (vinyl siding, plywood siding, asphalt shingle roofing, and cedar shake roofing). The critical flux for fire growth values was determined at 3‐min heat radiation exposure and simultaneous 300‐mm long flame exposure. Test specimens were exposed to various durations and intensities of drying prior to exposing them to heat radiation. Application of water or foam provided no noticeable protection. Gel was effective in providing protection even after 60 min of laboratory condition drying but was less successful when exposed to fire weather simulating accelerated drying. Some uncertainty is associated with the results of this work because of the variability of landscaping plants and gel wetting agent application uniformity. The intermediate‐scale test results were verified using full‐scale testing. Copyright © 2012 John Wiley & Sons, Ltd.