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CIB correlations for compartment burning rates and average gas temperatures are examined for accuracy, utility, and generality. The results are applied to modeling the fire on 9/11 in WTC 1. Specific information is used from the NIST investigation. It is demonstrated that simple heat transfer modeling can predict the truss steel rod temperatures for the E119 tests of WTC done by NIST. The CIB temperature correlation and steel truss modeling are used to predict burning conditions for the WTC 1 96th floor fire and compared to the NIST results. Here a consideration of fuel loads from 20 to 40?kg/m2 was considered compared to just 20 used by NIST. The results suggest that the fully insulated truss bar temperatures would achieve higher values for higher fuel loads. A critical steel truss temperature of 650°C could support failure of the trusses as a theory for the collapse of the towers.

Water spray remains the most effective, environment-friendly and economical way of fighting accidental or unwanted fires, and this is largely due to its thermal characteristics. The mechanism of fire suppression by sprinkler water sprays is influenced by numerous factors, which have been the focus of years’-long and on-going research studies to improve its extinguishing performances. A comprehensive review study was carried out in this study to assess the level of technological know-how and current state of research in the field. A total of 2473 published articles spanning 50?years (i.e. 1970–2020) were systematically collected and analysed, whereby more than 100 relevant articles were selected and integrated in the discussion. In particular, the review focuses on research relating to the interactions of sprinkler sprays with flame, fire plume and hot surfaces, aiming to provide a better understanding of the phenomena involved in fire suppression.

The ability of EfficientDet, a framework developed in 2019 for object detection, to automatically detect smoke plumes at a distance of several kilometers is demonstrated. Recent articles have raise...

A systematic approach was used to investigate the weathering-induced degradation of a common water–based intumescent coating. In this study, the coatings are intended for humid indoor applications on steel substrates. The coating contains ammonium polyphosphate, pentaerythritol, melamine, and polyvinyl acetate. By replacing each ingredient with a less water-soluble substance, the most vulnerable substances, polyvinyl acetate and pentaerythritol, were identified. Furthermore, the weathering resistance of the system was improved by exchanging the ingredients. The coatings were stressed by artificial weathering tests and evaluated by fire tests. Thermogravimetry and Fourier-transform infrared spectroscopy were used to study the thermal decomposition. This study lays the foundation for the development of a new generation of water-based intumescent coatings.

Firefighting bunker gear is manufactured from flame-retardant materials, which resist ignition and delay flame spread. However, concerns have been emerging on the potential harmful effects of some flame retardants (FRs) commonly used in flame-retarding materials, particularly the brominated flame retardants. This study investigated the presence of flame retardants in bunker gear, particularly polybrominated diphenyl ethers and their congeners in the garments, and evaluated their impact on thermal performance. X-ray fluorescence spectroscopy was used to ascertain the presence of bromine as a possible indicator for brominated flame retardants. X-ray fluorescence results indicated the presence of Br in all samples, ranging from 444 to 20,367 μg/g. Further analysis via gas chromatography–mass spectrometry was done on samples. Brominated flame retardants, particularly polybrominated diphenyl ethers and hexabromocyclododecane, were detected in all samples with concentrations ranging from 261.61 to 1001.77 μg/g and 0.01 to 0.07 μg/g, respectively. The cone calorimeter was used, with 50 and 75?kW/m2 heat fluxes, to investigate the impact of the brominated flame-retardant concentrations, if any, on thermal performance. New bunker garments, particularly those with lower Br and brominated flame-retardant concentrations, were observed to have higher thermal performance.

The effect of different cable layouts on the fire behavior of electric cable arrays was experimentally studied. The influence of external heat flux on cable fire characteristics was investigated. Several parameters for electrical cables such as the post-burning morphology, ignition time, heat release rate, peak heat release rate and total heat release were obtained. The results show that cable layouts could affect cable charring degrees according to the post-burning morphology. A linear relationship was found in the transformed form of time to ignition and radiant heat flux, and the critical radiant heat flux value for the single cable array appeared smaller than that for the other two layouts. The peak heat release rate for Cables A–D with the single array presents the increasing trend with an increase in radiant heat flux, while the two parallel and intersectional cable arrays present the different trends. Moreover, the total heat release values of Cables A–D in the different cable layouts were analyzed. This work provides the basic data and preliminary investigation to fire engineering of cable arrays with the different layouts.

This study presents the fire performance of typical components of wood structure buildings. The wooden beams and floor slabs, quite common in wood structure buildings, were burned with different fire exposure times by a pool fire source. Then, the surface temperature evolution and the charring rate were recorded and analyzed. The results show that the flashover and re-ignition phenomenon occurred in all wood materials under the burning pool fires. The glulam beam cross-section was U-shaped, and the maximum charring rates of glulam beam, cross-laminated timber floor, and cross-laminated timber partition board were 0.833 mm/min, 1.538 mm/min, and 0.435 mm/min, respectively. It can be seen that the combustion behavior time of specimens with different cross-section thicknesses is different. If the thickness of the specimens is appropriately increased, their combustion behavior time can be significantly improved.

The aim of this work is to study and characterize the fire behavior of vertically oriented spruce wood panels using experiments conducted at the scales of cone calorimeter and single burning item t...

Wood dust consists of the fine particles of wood that are produced when wood is processed. It is considered explosive, especially if it produces a dust cloud. Initiating the combustion process insi...

This review aims to present recent improvements and existing challenges in the design of wearable sensors used in the firefighters’ protective clothing. Wearable sensors are generally used directly on the body or placed on wearable items to monitor data for the safety of firefighters. Recently, wearable sensors have attracted much attention from researchers and experts. Most investigations have addressed novel designs for wearable sensors to enhance firefighters’ safety measures and reduce the risk of exposure to fires. This article is an attempt to review design limitations of wearable sensors for future developments and improve existing shortcomings. The growing body of knowledge focused on the application of wearable technology to monitor firefighters’ activity, health, and body temperature. In the following, we have discussed the trials of the design of the existing sensors. Finally, moisture and radiation as common exterior parameters in fire events are discussed which received less attention and have major impact on the performance of firefighters’ wearable sensors.