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The NIST National Fire Research Laboratory (NFRL) is a unique facility used to conduct real scale fire measurements. In 2015, the NFRL was expanded to enable research on the response of real-scale structural systems to realistic fire and mechanical loading under controlled laboratory conditions. The scientific objectives of the expanded NFRL are to develop an experimental database on the performance of materials, components, connections, assemblies, and systems under fire load. This data can be used by the international research community to validate and verify physics-based predictive models. The lab features two high bay test areas, a 18 m × 27 m strong floor with 1218 anchor points, a 9 m × 18 m strong wall with 420 anchor points, a hydraulic loading system, four large exhaust hoods instrumented for fire calorimetry, an emission control system for scrubbing acid gases and particles generated by real fuels, controlled gas and liquid fuel burners, water suppression systems, overhead cranes and conditioning space. The laboratory expansion was designed to accommodate experiments on real-scale structural systems and components up to two stories in height and 2 bays × 3 bays in plan. Through application of controlled loads, true service conditions can be simulated, and structures can be exposed to controlled and realistic fire conditions that grow, spread and decay with heat release rates as large as 20 MW. Measurement capabilities have been developed to characterize the response of structural systems and components up to failure and to characterize the fire heat release rate and thermal environment in real time. A detailed description of the laboratory is presented with an emphasis on measurement capabilities. [ABSTRACT FROM AUTHOR]

Fires that break out in tsunami inundation areas are collectively referred to as 'tsunami-induced fires' in contrast with 'seismic-induced fires' which have been conventionally a serious concern in Japan. Scenario of this new fire is basically as follows: (1) combustible objects such as houses are washed away by a tsunami, (2) combustible objects accumulate in tsunami inundation area as debris, (3) debris are ignited by some kind of cause, and (4) fires spread to adjacent debris resulting in conflagration in tsunami inundation area. We have been modeling tsunami-driven combustible objects as the first step towards development of tsunami-induced fire spread simulation. This modeling aims to know how combustible objects accumulate in tsunami inundation area to be the input data to fire models for ignition and fire spread. The proposed model is the extension of the existing model for driftwood by incorporating the debris release model and the effect of debris's collision with surviving buildings. This model collaborates with the existing numerical simulation of tsunamis and is able to predict the drift and accumulation behavior of individual debris by solving the equation of horizontal translational motion. In this paper, we conducted debris diffusion simulation for Yamada, Iwate prefecture, Japan for model's validation, where 16 ha of area were affected by tsunami-induced fire spread after the 2011 Great East Japan Earthquake Tsunami. The total number of debris tracked in the simulation was 1,850,560. A constant of proportionality, which determines the severity of force acting on drifting debris due to the collision with onshore surviving buildings, was identified by trial and error to maximize the eventual amount of accumulating debris within the fire-damaged zone. As a result, this maximum amount was predicted to be 4654 tons in the case that the constant is 0.1. Two thirds of the released debris, about 12,000 tons, accumulated onshore at the end of computation, and most of the fire-damaged zone was covered by these debris. [ABSTRACT FROM AUTHOR]

The paper highlights key components of a fire model validation study conducted by the U.S. Nuclear Regulatory Commission and the Electric Power Research Institute. These include the selection of fire phenomena of interest to nuclear power plant safety, the selection of appropriate models, the selection of relevant experimental data, and the selection of appropriate evaluation criteria. For each model and each quantity of interest, there are two metrics of accuracy. The first is a bias factor, which indicates the extent to which the model tends to over or under-predict the given quantity. The second is a relative standard deviation, which indicates the degree of scatter in the predicted quantity when compared with experimental measurements. While the study is motivated by nuclear power plant safety, the general procedure and results are appropriate for most industrial applications. [ABSTRACT FROM AUTHOR]

The paper considers what is meant by, and the purpose of, blind modelling in the context of fire engineering. A discussion is presented on the very important interaction between the model and the model users, and five generic groups of model users are defined. The paper goes on to provide details of previous blind modelling studies from the literature, as well as a recent blind modelling programme that was conducted in New Zealand. A so-called 'Openness Assessment Framework' is proposed as a way of scoring or ranking existing or planned blind modelling programmes, with the recent New Zealand programme forming the case study for the evaluation. This framework is then applied to a range of evaluation definitions that are given in the literature, the five generic model user groups, as well as the range of blind modelling exercises already identified. Finally, a seven-step methodology for designing blind modelling studies and experimental comparisons in the context of full-scale multi-item compartment fire experiments is proposed. [ABSTRACT FROM AUTHOR]

To date there is no International standard on the verification and validation (V&V) of building fire evacuation models, i.e., model testers adopt inconsistent procedures or tests designed for other model uses. For instance, the tests presented within the MSC/Circ.1238 Guidelines for evacuation analysis for new and existing passenger ships provided by the International Maritime Organization are often employed for the V&V of models outside their original context of use (building fires instead of maritime applications). This paper presents a list of verification tests for component testing and the analysis of emergent behaviours together with examples of experimental data-sets suitable for the analysis of different core components. The capabilities of building fire evacuation models are evaluated by studying their five main core components, namely (1) pre-evacuation time, (2) movement and navigation, (3) exit usage, (4) route availability and (5) flow constraints. This paper discusses the tests which are included in a freely available Technical Note developed at the National Institute of Standards and Technology. This work is intended to open a discussion on the main issues associated with the definition of a standard procedure for the V&V of building fire evacuation models, including the definition of the acceptance criteria of a standard V&V protocol. [ABSTRACT FROM AUTHOR]

Periods of fire resistance are pervasive in the field of fire engineering. They are the basis of prescriptive structural fire guidance and also the end result of some quantitative analyses. Time equivalence methods are one such calculation approach that is used to define periods of fire resistance. However, these calculations often do not inherently consider the fundamental design challenges. These challenges are the fire safety goals and the constraints of the building and the physical world. The appropriate balance of these challenges is a solution. This paper further defines these concepts and gives examples of their application in the context of time equivalence analysis. It is found that the existing time equivalence methods do not adequately consider the challenges. An alternative framework, adopting a risk based approach, enables appropriate consideration of the goals and constraints to obtain a solution for structural fire resistance. This approach is sufficiently flexible that its component pieces can be improved and updated as new engineering techniques become available. [ABSTRACT FROM AUTHOR]

Firefighting robots are actively being researched to reduce firefighter injuries and deaths as well as increase their effectiveness on performing tasks. There has been difficulty in making firefighting robots autonomous because the commonly used sensors for autonomous robot navigation do not perform well in fire smoke-filled environments where low visibility and high temperature are present. In order to overcome these limitations, a multi-spectral vision system was developed that uses sensor fusion between stereo thermal infrared (IR) vision and frequency modulated-continuous wave (FMCW) radar to locate objects through zero visibility smoke in real-time. In this system, the stereo IR vision was used to obtain 3-D information about the scene while the radar provided more accurate distances of objects in the field of view. Through globally matching radar objects with those in the 3-D image, the accuracy of the stereo IR vision map was updated removing the far-field inaccuracy of the stereo IR as well as ghost objects created due to stereo mismatch. The system was sufficiently fast to provide real-time matching of objects in the scene allowing for dynamic reaction object tracking and locating. Through large-scale fire experiments with and without smoke in the field of view, the distance error for the stereo IR vision was reduced from 1% to 19.0% to 1% to 2% due to sensor fusion of the stereo IR with FMCW radar. [ABSTRACT FROM AUTHOR]

Fire source distinction is useful in reducing the occurrence of false alarms and in choosing an effective fire extinguishing medium. This study was aimed at distinguishing fire sources through a smoke analysis. For this purpose, a smoke detection chamber was created, which was equipped with one light source and several light sensors for enabling simultaneous detection of light extinction and scattering, respectively. The test fires considered in this study had two kinds of sources: single fire source (paper, wood, and flammable liquid) and mixed fire source (paper-wood, paper-flammable liquid, and wood-flammable liquid mixtures). The amounts of extinction and scattering for each fire were measured experimentally, and the discrete probability distributions were calculated from the measured scattering amount. The optical characteristics of each fire were obtained using extinction data and the calculated probability distributions. These optical characteristics were then used for learning of neural networks, and the learned neural networks were used to distinguish fire sources from smoke generated in the case of both single fires and mixed fires. Results revealed that the neural networks could precisely distinguish fire sources on the basis of the smoke particles in the case of both single fires and mixed fires. The results of this study are expected to be useful in developing an advanced smoke detector that can distinguish fire sources in addition to detecting smoke. [ABSTRACT FROM AUTHOR]

Fire safety is an important issue of building safety, especially when the building’s fire load contents enhance the risks of fire deflagration. When existing timber structures are involved, the most usual way to improve its reaction to fire is to treat wood with fire retardants. This study focuses on the surface protection of existing timber roof structures against fire, through the use of fire retardant (FR) treatments applied on site. An experimental investigation was carried out to study the effect of FR treatments on timber reaction to fire, with a special emphasis on timber members with biological deterioration and previously treated with preservative products. The behaviour and effectiveness of intumescent and non-intumescent treatments was also investigated. The study showed that the application of FR treatments improved the reaction to fire of timber, even in the presence of previous preservative treatments. However, the choice of the specific FR treatment should take into account the substrate conditions. In addition, test results suggest that protection systems involving multi layers (intumescent and non-intumescent) with different functioning modes each are likely to have a good global performance on the protection of timber elements against fire. [ABSTRACT FROM PUBLISHER]

In current practice, no special measures are applied for enhancing structural fire safety of steel bridge girders. Further, there is very limited information and research data in the literature on the fire resistance of structural members in bridges. In this paper, the fire response of a steel bridge girder under different conditions is evaluated using the FEM computer program ANSYS. In the analysis, the critical factors that influence fire resistance, namely, fire scenario, fire insulation, and composite action arising from steel-concrete interaction, are accounted for. Results from numerical studies show that the composite action arising from steel-girder-concrete-slab interaction significantly enhances the structural performance (and fire resistance) of a steel bridge girder under fire conditions. Other significant factors that influence fire resistance of steel bridge girders are fire insulation and type of fire scenario. [ABSTRACT FROM AUTHOR]

Abstract: Various types of fires occurred following the Great East Japan Earthquake on 11 March, 2011 in extensive areas across the Tohoku and Kanto districts. It was, of course, difficult for a limited number of fire researchers to thoroughly investigate the fires, which were distributed over extremely wide areas. Nevertheless, it was necessary to make the investigations before the fire scenes had been lost with time. A joint effort was made by people from universities, national research institutes and industries related with fire research and safety. Although it will take some more time before satisfactory results of the investigation are made public, this paper attempts to outline the peculiar features of the fires that have been revealed at this point. [Copyright &y& Elsevier]

Accurate characterization of the thermal environment in fires and fire safety tests is crucial to understanding the impact of fire on materials and assemblies and the work on modeling those impacts. Standardized fire resistance test methods have been used to help evaluate building materials and assemblies since the early 1900s and have been part of a successful effort to improve fire safety. However, current methods use predominately temperature measurements and do not provide sufficient heat transfer data to support the development and validation of fire protection engineering models. This paper looks at measurement techniques that were used successfully in pool fire research and how they could be applied to modeling structure fires. [ABSTRACT FROM AUTHOR]

Comments on the research paper "Fire Behavior in Rooms," by Kunio Kawagoe. Factors measured in the first experiment in 1948; Basis for determining fire resistance; Calculation of temperature.

This study is based on 1977-78 data reported to the National Fire Data Center through the National Fire Incident Reporting System (NFIRS). In 1977, eight states reported over 350,000 fire incidents; in 1978, 15 states reported over 443,000 incidents. The purpose of this report is to present to the textile industry a comprehensive picture of the involvement of textile products in fires, to assist it in focusing its research and development on the most important targets. The data on causes of textile fires indicate that most of them start because someone misused a source of heat or misused the material ignited. But this does not relieve the textile industry from the responsibility for working to reduce the flammability of textile products. [ABSTRACT FROM AUTHOR]

Summarizes the issues published in the journal "Society and Natural Resources" on fire social science and management actions for fire prevention. History of fire social science; Research perspectives that address the question of the effective integration of fire social science; Applicability of natural hazard research on fire management.