Comparison of Fire Model Predictions with Experiments Conducted in a Hangar With a 15 Meter Ceiling

The purpose of this study is to examine the predictive capabilities of fire models using the results of a series of fire experiments conducted in an aircraft hangar with a ceiling height of about 15 m. This study is designed to investigate model applicability at a ceiling height where only a limited amount of experimental data is available. This analysis deals primarily with temperature comparisons as a function of distance from the fire center and depth beneath the ceiling. Only limited velocity measurements in the ceiling jet were available but these are also compared with those models with a velocity predictive capability

Thermal oxidative decomposition estimation combining TGA and DSC as optimization targets for PMMA

Thermal analysis techniques play a key role to determine and characterize solid phase thermal decomposition. In this sense, Simultaneous Thermal Analysis (STA, i.e. TGA and DSC tests carried out simultaneously) are widely employed, since it provides information about how mass is lost and energy released while the temperature of the sample increases. Fire computer models combined with methods numerical methods are widely used to represent the results from tests and to achieve the values of the kinetic and thermal parameters. Previous works looked forward achieving those parameters using, as unique optimization target, the mass loss curve (TGA) or its derivative (DTGA). As the study of heat release rate is a decisive element to characterize the material properly, most recent works were adding additional measures. These extra measurements concern the heat transfer and the energy required or released during temperature programmed heating, such as heat rate release, heat of gasification, or the surface temperatures of the samples. The information about the energy is provided by the Differential Scanning Calorimetry curve (DSC). Despite of the employment of the information provided by the DSC, this information usually is not used as a target to approach the DSC simulated curve to the experimental one as TGA does. Based on the lack of use of the DSC curve as numerical approaching process to set the kinetic properties, we decide to explore the possibility of adding this as a new target in the process. Therefore, kinetic and thermal properties might be achieved fitting experimental and simulated curves simultaneously, which should allow us to take into account the decomposition process and their energy released. Results obtained in the present work reveal the major challenge of getting a set of parameters, which can fit DSC curve. The level of accuracy reached when only TGA is utilized as target to approach is higher than the level of accuracy of DSC curve. This fact makes increase the value of the errors when both curves are used as targets to approach. In other words, an approach to both curves simultaneously cannot be directly made. With this consideration in mind, this paper proposes an alternative methodology in order to fit TGA curve considering the optimization of the DSC curve. The methodology proposed in the present work is applied to the analysis of poly(methyl methacrylate) (PMMA).The authors would like to express their thanks to the Nuclear Safety Council for the cooperation and cofinancing of the project "Simulation of fires in nuclear power plants" and the Spanish Ministry of Economy and Competitiveness for the PYRODESIGN Project grant, Ref.: BIA2012-37890, financed jointly by ERDF

Development of an International SMA Bulbar Assessment for Inter-professional Administration

BACKGROUND: Progressive weakness can affect bulbar muscles in individuals with moderate to severe forms of spinal muscular atrophy (SMA). The paucity of standardized, valid bulbar assessments capturing clinically significant deficits in SMA impedes the ability to monitor function, facilitate intervention, or detect treatment response. OBJECTIVE: To fill this void, an international multidisciplinary team gathered to develop an agreed upon consensus-derived assessment of bulbar function in SMA for inter-professional administration to enhance our ability to monitor disease progression, support clinical management, and evaluate treatment effects. METHODS: Fifty-six international clinicians experienced in SMA were invited and engaged using the Delphi method over multiple rounds of web-based surveys to establish consensus. RESULTS: Serial virtual meetings occurred with 42 clinicians (21 speech and language therapists, 11 physical therapists, 5 neurologists, 4 occupational therapists, and 1 dentist). Seventy-two validated assessments of bulbar function were identified for potential relevance to individuals with SMA (32 accessible objective, 11 inaccessible objective, 29 patient-reported outcomes). Delphi survey rounds (n = 11, 15, 15) achieved consensus on individual items with relevance and wording discussed. Key aspects of bulbar function identified included: oral intake status, oral facial structure and motor strength, swallowing physiology, voice & speech, and fatigability. CONCLUSIONS: Multidisciplinary clinicians with expertise in bulbar function and SMA used Delphi methodology to reach consensus on assessments/items considered relevant for SMA across all age groups. Future steps include piloting the new scale moving towards validation/reliability. This work supports the advancement of assessing bulbar function in children and adults with SMA by a variety of professionals

Fire-induced structural failure: the World Trade Center, New York

Fire investigation has generally concentrated on determination of the cause and origin of a fire. Methodologies developed for this purpose have thus focused on the dynamics of fire growth and investigation of its effect on different objects within the structure affected by the fire. It is unusual to see a fire investigation emphasising structural damage as a way to obtain information for fire reconstruction. The series of dramatic fire events that occurred on 11 September 2001 within the World Trade Center, New York complex have emphasised the need to introduce structural analysis as a companion to evaluation of a fire timeline. Only a combined analysis is capable of providing a complete reconstruction of the event and therefore a solid determination of causality. This paper presents a methodology to establish, by means of modern structural and fire analysis tools, the sequence of events leading to a structural failure. This analysis will be compared with classic cause and origin techniques, emphasising the importance of a comprehensive study. Specific structural features and fire conditions that lead to unique forms of failure will be discussed, establishing the complexity of linking fire, structure characteristics and failure mode. The collapse of buildings 1 and 2 of the World Trade Center will be used to illustrate different forms of failure and the fires that cause them

Modelling the effects of boundary walls on the fire dynamics of informal settlement dwellings

AbstractCharacterising the risk of the fire spread in informal settlements relies on the ability to understand compartment fires with boundary conditions that are significantly different to normal residential compartments. Informal settlement dwellings frequently have thermally thin and leaky boundaries. Due to the unique design of these compartments, detailed experimental studies were conducted to understand their fire dynamics. This paper presents the ability of FDS to model these under-ventilated steel sheeted fire tests. Four compartment fire tests were modelled with different wall boundary conditions, namely sealed walls (no leakage), non-sealed walls (leaky), leaky walls with cardboard lining, and highly insulated walls; with wood cribs as fuel and ISO-9705 room dimensions. FDS managed to capture the main fire dynamics and trends both qualitatively and quantitatively. However, using a cell size of 6 cm, the ability of FDS to accurately model the combustion at locations with high turbulent flows (using the infinitely fast chemistry mixing controlled combustion model), and the effect of leakage, was relatively poor and both factors should be further studied with finer LES filter width. Using the validated FDS models, new flashover criteria for thermally thin compartments were defined as a combination of critical hot gas layer and wall temperatures. Additionally, a parametric study was conducted to propose an empirical correlation to estimate the onset Heat Release Rate required for flashover, as current knowledge fails to account properly for large scale compartments with thermally thin boundaries. The empirical correlation is demonstrated to have an accuracy of ≈ ± 10% compared with the FDS models

Protocol for a cluster randomised controlled trial to determine the effectiveness and cost-effectiveness of independent pharmacist prescribing in care home: the CHIPPS study

Background: Prescribing, monitoring and administration of medicines in care homes could be improved. Research has identified the need for one person to assume overall responsibility for the management of medicines within each care home. and shown that a pharmacist independent prescriber service is feasible in this context. Aims and objectives: To conduct a cluster randomised controlled trial to determine the effectiveness and cost-effectiveness of a pharmacist-independent prescribing service in care homes compared to usual general practitioner (GP)-led care. Objectives: To perform a definitive randomised controlled trial (RCT) with an internal pilot to determine the intervention’s effectiveness and cost-effectiveness and enable modelling beyond the end of the trial. Methods: This protocol is for a cluster RCT with a 3-month internal pilot to confirm that recruitment is achievable, and there are no safety concerns. The unit of randomisation is a triad comprising a pharmacist-independent prescriber (PIP) based in a GP practice with sufficient registered patients resident in one or more care homes to allow recruitment of an average of 20 participants. In the intervention group, the PIP will, in collaboration with the GP: assume responsibility for prescribing and managing residents’ medicines including medication review and pharmaceutical care planning; support systematic ordering and administration in the care home, GP practice and supplying pharmacy; train care home and GP practice staff; communicate with GP practice, care home, supplying community pharmacy and study team. The intervention will last 6 months. The primary outcome will be resident falls at 6 months. Secondary outcomes include resident health-related quality of life, falls at 3 months, medication burden, medication appropriateness, mortality and hospitalisations. A full health economic analysis will be undertaken. The target sample size is 880 residents (440) in each arm) from 44 triads. This number is sufficient to detect a decrease in fall rate from 1.5 per individual to 1.178 (relative reduction of 21%) with 80% power and an ICC of 0.05 or less. Discussion: Recruitment is on-going and the trial should complete in early 2020. The trial results will have implications for the future management of residents in care homes and the ongoing implementation of independent pharmacist prescribing. Trial registration: ISRCTN, ID: 17847169. Registered on 15 December 2017

The Optimal Tax Treatment of Housing Capital in the Neoclassical Growth Model

In a dynamic setting, housing is both an asset and a consumption good.But should it be taxed like other forms of consumption or like other forms of saving?We consider the optimal taxation of the imputed rent from owner housing within a version of the neoclassical growth model.We find that the optimal tax rate on the imputed rent is quite sensitive to the constraints imposed on the other available tax rates.In general, it is not optimal to tax the imputed rent at the same rate as the business capital income

Modelling a Historic Oil-Tank Fire Allows an Estimation of the Sensitivity of the Infrared Receptors in Pyrophilous Melanophila Beetles

Pyrophilous jewel beetles of the genus Melanophila approach forest fires and there is considerable evidence that these beetles can detect fires from great distances of more than 60 km. Because Melanophila beetles are equipped with infrared receptors and are also attracted by hot surfaces it can be concluded that these infrared receptors are used for fire detection