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Modelling capabilities have drastically improved in the last decade. However, in most of the cases the fire response of building elements is predicted by fitting input material properties to the models in order to match test data. This paper presents models developed to predict the unexposed side temperature of stone wool layered composites with stainless steel or gypsum claddings exposed to severe heat conditions. The suitability of material thermal properties from literature and reaction kinetic parameters obtained at bench scale (e.g. thermogravimetric analysis, bomb calorimeter, slug test) to model composites at different heat exposures is studied. Modelling efforts include: (1) the combustion of the organic content of the wool, (2) diffusion term to account for the passage of hot air through the wool, (3) calcination reactions in the gypsum plasterboard, (4) energy released by burning of the paper lining of gypsum plasterboard. The models are compared against experimental data. Results show that material thermal properties of gypsum plasterboard and stone wool retrieved from the literature and obtained at a bench scale provide accurate model predictions under different heat exposures. Furthermore, reactions schemes for the dehydration of gypsum plasterboard and organic content combustion in the wool also provide good modelling results. Further analysis is necessary to understand the environmental conditions inside the layered composites in fire exposures in order to achieve better modelling predictions.

This paper examines the structural response of cold-formed steel-framed building lateral force-resisting systems under combinations of simulated earthquake and fire loading. Full-scale experiments with gypsum-sheet steel composite panel sheathed walls, oriented strand board sheathed walls, and steel strap braced walls are presented. Twenty-two test specimens are subjected sequentially to combinations of cyclic shear deformation and fires of varying intensity; some approximate temperatures in standard furnace tests, and most have characteristics of actual building fires. In select tests, the walls are predamaged to simulate fire following an earthquake. The results show a progressive decrease of postfire lateral load capacity with increasing fire intensity for all walls; however, each wall type exhibits varied sensitivity to the fire intensity as well as to predamage. By understanding the response of these structural systems in real fires, designers can better plan for situations in which multiple hazards, including fire, exist.

This article presents the experimental results of stone wool–layered sandwich constructions, with either steel or gypsum claddings, tested under four different heating exposures: 7 kW/m2 incident radiant heat flux exposure, 60 kW/m2 incident radiant heat flux exposure, parametric time–temperature curve exposure and ISO 834 standard time–temperature exposure. The test apparatus used were a movable radiant panel system, a mid-scale furnace (1.5 m3) and a large-scale furnace (15 m3). The results show that reduced-scale tests are capable of reproducing the heat transferred through the construction at large scale provided there is limited mechanical degradation. The results indicate that the availability of oxygen is fundamental to the fire behaviour of the sandwich composites tested. Reactions occurring in stone wool micro-scale testing, such as oxidative combustion of the binder or crystallisation of the fibres, have a limited effect on the temperature increase when wool is protected from air entrainment.

Prediction of the insulating capability of building products in fire conditions would support the product development process. Stone wool insulation is a widely used material in fire barrier constructions. Due to the combustion of its organic content, the temperature inside stone wool can rise above the temperature of the exposed boundary. This temperature rise is difficult to predict. An extensive test program was performed to obtain the thermal and reaction kinetic properties of stone wool. The test methods included modified slug calorimeter, thermogravimetric analysis, differential scanning calorimetry, micro-scale combustion calorimetry and bomb calorimetry. The thermal conductivity in elevated temperatures was similar for all the investigated products. Two positive mass loss rate and heat release rate peaks were observed in temperatures between 20°C and 700°C. Reaction kinetic parameters were obtained and used in a finite difference model predicting the temperature increase in stone wool upon linear heating.

This paper presents results of large-scale experiments with varying levels of fire severity on lateral force-resisting systems commonly used in cold-formed steel framed buildings. Gypsum-sheet steel composite panel sheathed walls, oriented strand board sheathed walls, and steel strap-braced walls are examined. Postflashover fire conditions of two different intensities as well as 1 hour of fire exposure similar to that in a standard furnace qualification test are studied. Additionally, a full-scale furnished kitchen fire experiment is conducted for comparison. The results highlight differences in the thermal response and subsequent performance of the walls as well as differing sensitives of the walls to pre-damage, eg, that might occur during an earthquake. The results are part of a larger effort to provide fragilities for these wall systems in response to realistic fires for performance-based design.

Background Patients with Idiopathic nonhistaminergic angioedema appear to have similar clinical features and pathogenesis as those with hereditary angioedema. Icatibant, a selective bradykinin β2 receptor antagonist, licensed for use in acute attacks of hereditary angioedema could be also effective in treating other forms of angioedema. We report a patient with idiopathic angioedema who was successfully treated with icatibant. Methods A 77-year-old man with a history of arterial hypertension currently treated with hydrochlorothiazide and type II diabetes under insulin treatment. He had suffered from recurrent angioedema attacks located on his tongue without urticaria during the last 7 years. Serum levels of C1-INH, C4 and C1q and C1-INH activity were normal. In spite of cessation of treatment with ACE inhibitors and RAAS-blockers (he had been treated with enalapril and losartan previously) he continued with the angioedema attacks. As no cause of angioedema could be identified and the angioedema did not response to antihistamines, the patient was diagnosed of idiopathic nonhistaminergic angioedema. In one of the episodes he was admitted at the emergency room with a swollen tongue. The edema gradually progressed in spite of the treatment with antihistamines, corticosteroids and epinephrine. Tracheotomy was considered due to the severity of the angioedema that began to cause airway compromise. After consulting the Allergy Unit, treatment with icatibant was administered. Results Approximately 30 minutes after the subcutaneous administration of icatibant 30 mg the symptoms improved and the angioedema resolved completely within 6 hours. The only adverse effect following the icatibant administration was pain localized in the injection site. After 5 months the patient suffered a similar attack that was also successfully treated with icatibant sc. Conclusions Icatibant administered subcutaneously provided an effective and well-tolerated treatment option for acute angioedema attacks in a patient with idiopathic nonhistaminergic angioedema. This form of angioedema could have a pathogenic mechanism similar to the bradikinin mediated angioedema. We suggest the use of icatibant in the treatment of severe attacks of angioedema in patients that do not response to antihistamines, corticosteroids and epinephrine.