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Fires in enclosures equipped with mechanical ventilation remain one of the key issues for fire safety assessment in multifamily homes and industries. Therefore, a wide variation of methods for preventing smoke spread through the ventilation system exist and are applied, in performance-based designs. Through the use of the heating, ventilation and air conditioning (HVAC) model in the fire dynamics

This work has been made as a thesis for a BSc degree in Fire Protection Engineering at Lund University. The work has been supported and funded by ESS AB, European Spallation Source, in Lund. ESS AB is a publicly held company, owned by Sweden and Denmark as host countries. These host countries, together with at least 17 other European countries, will build and establish a multidisciplinary research

The characteristics of smoke are highly dependent on the materials undergoing thermal decomposition and the environment in which this decomposition takes place. With the rising complexity in dedicated fire simulation tools, there is a need for increased information on the composition and properties of smoke in order to develop/validate and extend the fire safety engineering community's smoke and v

Traditionally in fire modelling, a solid fuel has been assumed to ignite when the solids surface reaches a specific temperature or when the heat flux upon the solid reaches a critical level. Although these approaches of determining ignition for the condensed phase are practical, ignoring the gas phase conditions may lead to incorrect assumptions regarding material safety. A more 'physical' explana

It has been shown in previous studies that the current standard used to fire test interior materials in civilian and military vehicles, ISO 3795 (FMVSS 302), has led to a low level of fire safety of interior materials in civilian vehicles. The purpose of this study was to evaluate the fire safety of interior materials in military vehicles. The aim was to suggest a fire test method to be used on in

The current fire testing and classification system and corresponding tests is mainly based on prescriptive building fire codes. This has certain limitations resulting in restricting the possible use of these tests for performance-based design within fire safety engineering (FSE). It also restricts innovation and cost-efficiency for companies supplying materials/components for buildings and transpo

The Cone Calorimeter test method has been for years one of the most used small-scale fire test methods. It is certainly one of the methods which is most widely spread over the world at this moment. In contrast to many other fire test methods, the Cone Calorimeter provides a range of data with sound scientific basis, which allows a wide range of applications. In this article five different areas of

Three types of high-resilience PU foam representing a wide range of combustion performance are tested in conjunction with three fabrics: polyester, polypropylene and flame-retardant cotton. It is shown that covering of the foam with fabric usually results in a delay of ignition and peak rate of heat release. Mock-up performance is mainly influenced by the fabric, but is also influenced by the qual

The first part of this study focuses on the effect of cone calorimeter test variables on polyurethane flexible foam properties such as ignitability, heat release rate, effective heat of combustion and mass loss. Three of the main commercial foam types were used, i.e. conventional slabstock foams, high‐resilience slabstock foams and all‐MDI (methylene diphenyldiisocyanate) moulded foams. A decrease

The relative contributions of fabric and foam on important fire hazard parameters as measured in the cone calorimeter were determined for various mock‐up combinations. Three commercial types of high‐resilience PU flexible slabstock foams, representing a wide range of combustion performance, were combined with three different fabrics: polyester, polypropylene and combustion‐modified cotton. Total h

This paper summarizes the second part of a study over a two year period carried out at the Laboratory for Fuel Technology and Heat Transfer of the University of Gent in cooperation with Dow Benelux N.V.. The first part of the study, focusing on the effects of cone calorimeter test variables as well as polyurethane (PU) flexible foam variables on the foam combustion characteristics, has been publis

The relative contributions of fabric and foam on important fire hazard parameters as measured in the cone calorimeter were determined for various mock-up combinations. Three commercial types of high resilience PU flexible slabstock foams, representing a wide range of combustion performance, were combined with three different fabrics; viz. polyester, polypropylene and combustion modified cotton. To

The first part of this study focused on the effect of cone calorimeter test variables on polyurethane flexible foam properties such as ignitability, heat release rate, effective heat of combustion and mass loss. Three of the main commercial foam types were used; viz. conventional slabstock foams, high resilience slabstock foams and all-MDI moulded foams. A decrease in heat flux (down to 40%) with

Based on a review of studies of functional and comparative anatomy of crustacean eyes, a hypothesis is formed on eyes in primitive crustaceans. It is suggested that they were similar to present-day frontal eyes of the malacostracan type. Neuronal architecture suggests that the development to apposition compound eye followed two main routes, one seen in malacostracansand the other in non-malacostra

The digestive tract of the cephalocarid Hutchinsoniella macracantha begins with an atrium oris, posterior to the mouth. The esophagus loops up through the head and ends with a valve to the midgut. The epithelial cells and cuticle of both these structures are connected with long, winding, apically distended microvilli. The midgut is a straight tube with a pair of diverticula anteriorly. Midgut epit

Immunoreactivity to antisera raised against scrotonin, a biogenic amine, and FMRFamide, a neuropeptide, reveals two different populations of neurons in the nervous system of Hutchinsoniella macracantha. Neural transmission may thus use at least transmitter substances that are found in other crustaceans and invertebrates.

The structure of the aesthetascs has been investigated in the prawn Macrobrachium rosenbergii (larvae and juveniles), the opossum shrimp Neomysis integer, the euphausid Meganyctiphanes, and in the water-fleas Daphnia magna and D. longispina. The aesthetascs, that are thought to represent olfactory receptors, exhibit a considerable structural variation, ranging from the well known aesthetascs of hi

The primary excretory organ of adult Hutchinsoniella macracantha is the maxillary gland, which is located laterally in the posterior portion of the cephalon. It consists of an end sac and a tubule which is divided into proximal and distal sections. The end sac is composed of podocytes filled with endocytotic vesicles which grade in size upward to a large residual body. A large valve controls the o