Smoke and fire dynamics in atria and large enclosures: An overview

The proliferation of atria within modern large buildings is relatively recent. An atrium can be defined as a large open space connecting two or more storeys. Atria are important architectonical features since the 60's and can be found, among others, in shopping centres, office buildings and high-rise buildings, airports, stations and sports centres. However, the atrium represents an innovative, complex and non conventional architectonical element that can lead to fire environments diverging significantly from those in conventional compartments used in the development of current codes and standards. They are a source of discussion in the fire safety community because smoke can easily spread from one floor to another making the traditional methodologies for compartmentation of little or null effect. The design of smoke management in atria has been based on prescriptive codes since the 70's. It was not until the mid 80's that the phenomena started to be the objective of both experimental and numerical studies. It is because of the subsequent improved understanding on fire dynamics and smoke management together with the increased computing power available nowadays, that there is a progressive movement from prescriptive-based to performance-based codes which is also chaning the way atria are designed. The aim of the present work is to provide a broad overview of the current state-of-the-art of fires in atria. A brief introduction to the characteristics and types of atrium structures is presented first. Then, a description of the fire dynamics as well as the main safety problems that arise in case of fire are considered. A historical discussion of the research, including experimental and numerical studies, is presented, and current design methodologies and fire safety strategies are discussed. The final part of the overview addresses the international tendencies towards the introduction of performance-based fire protection codes. This overview highlights the need for further experimental studies and validations of numerical simulations for a wider range of fire conditions. © 2010 by Nova Science Publishers, Inc. All rights reserved

Concerns on installing long-throw sprinklers in tall halls

There are concerns over long-throw sprinkler installation in halls with high ceilings which are likely to store large amount of combustible materials. These concerns will be addressed in this paper. At the moment, it is unknown whether such sprinkler installation can protect high-ceiling halls which store large amount of combustibles. The concept should be further explored with in-depth research through full-scale burning experiments with big fires.published_or_final_versio

Smoke management issues in buildings with large enclosures

Buildings that provide sporting, entertainment, and leisure facilities (e.g. sports arenas, exhibition halls, etc) can often contain large enclosed spaces or voids. In the event of a fire, these buildings often require the use of a smoke management system to provide conditions for safe means of escape for the building occupants. This paper raises a range of issues relating to smoke management in buildings with large enclosed spaces, including smoke management methods, design scenarios and some simple calculation methods. Experience of actual installed systems in real buildings has led to concerns on the efficacy of some smoke management systems, especially over the lifetime of a building. This paper discusses some of these concerns, real examples of sources of failure, and the importance of proper documentation, commissioning, maintenance and testing of these systems. As a way of addressing these concerns, a process validation methodology is presented to evaluate the design, the designer, the implementation of the design, and the long-term management, operation and maintenance of such systems

An analytical model on static smoke exhaust in Atria

Static smoke exhaust systems with natural vents are starting to be installed in big shopping complexes, ware‐houses and cargo terminals in the Far East. These systems are used for natural ventilation as well as for letting out smoke. This paper responds to concerns over the performance of static smoke exhaust systems, which remain less popular than dynamic smoke exhaust systems with mechanical fans. We propose a modification of a simple flow model found in the literature, adapting this to study smoke layer interface height with natural vents opened. We compare and justify our results, as generated by both Computational Fluid Dynamics and zone models, alongside reports of historical field tests. The model of smoke exhaust is applied in an illustrative example of a large hall, leading to the suggestion that a flow model could be used for designing natural vents. As the key driving force in removing smoke through natural vents is smoke's own buoyancy, the system might only be effective for bigger fires. Santrauka Tolimuosiuose Rytuose statines dūmu šalinimo sistemos su natūralios ventiliacijos angomis pradedamos irengti dideliuose prekybos kompleksuose, sandeliuose ir kroviniu terminaluose. Tokios sistemos naudojamos ir natūraliai ventiliacijai, ir dūmams šalinti. Šis straipsnis parengtas susirūpinus, kad statines dūmu išmetimo sistemos yra ne tokios populiarios nei dinamines dūmu išmetimo sistemos su mechaniniais ventiliatoriais. Autoriai siūlo literatūroje aprašomo paprasto srauto modelio modifikacija, pritaikant ši modeli dūmu sluoksnio salyčio su natūralios ventiliacijos angomis aukščiui tirti. Straipsnyje palyginti ir pagristi rezultatai, gauti taikant tiek skaičiuojamosios skysčiu dinamikos, tiek zonavimo modelius kartu su eksperimentiniais tyrimais vietoveje. Pateiktas dūmu šalinimo modelio taikymo pavyzdys dideleje saleje ir padaryta išvada, kad srauto modelis galetu būti taikomas irengiant natūralia ventiliacija. Kadangi pagrindine varomoji jega šalinant dūmus per natūralias ventiliacijos angas yra dūmu plūdrumas, sistema gali būti veiksminga tik esant didesniems gaisrams. First Published Online: 10 Feb 2011 Reikšminiai žodžiai: dūmu šalinimo sistemos, natūralios ventiliacijos angos, plūdrumas, dūmu sluoksnio salyčio aukšti

Idea, Form, Reality – the Implications of Natural Ventilation Strategies on public Buildings in Temperate Maritime Climates

Natural ventilation is one of the prime form givers in environmentally responsive architecture – in its detail and its architecturally charged form of stacks and voids. It facilitates our understanding of a response to natural systems – not just in how it responds visually to warm and cool air but also in the adaptive approach to thermal comfort. The purpose of this research is to investigate the impacts and implications of natural ventilation strategies for different typologies of public and commercial buildings. This is with the aim of attempting to define a vocabulary of ventilation techniques and details that are suited to particular categories of buildings within the temperate maritime climate of Europe. The effectiveness of the natural ventilation strategies are investigated through the parameters of energy usage, internal air quality, thermal comfort and operation. Following these, the different architectural responses to the physics of natural ventilation have been examined and in particular in the more detailed responses of differing building types. From this we can start to define appropriate strategies and the formal response of building types to natural ventilation

Inner 'Green' Space A Study of Conservationism in Atrium Spaces Using Academic Buildings in Southern Ontario

Since taking hold in the mid 1960s, the modern atrium has become prevalent in many designs and buildings within contemporary architecture. The modern day atrium has endured to find its place amidst our current technologies and design aspirations by continuing to offer a capacity for assisting in urban strategies, providing strong economic returns on investment, conserving or recycling existing buildings, and for its potential to reduce energy consumption. Today, as concerns for energy and the environment rise to prominence within contemporary opinion, the reliance on more integrated conservational design strategies such as what the atrium offers in the matter of material and energy conservation is more relevant than ever. Yet simply including an atrium space within a building does not guarantee its effectiveness in realizing the potential for sustainable design. By selecting to survey a collection of recently completed academic buildings in Southern Ontario, the thesis aimed to examine what current reality exists in our use of the atrium with regards to its conservational characteristics. By examining the atrium’s ability to integrate sustainable design strategies in three areas: the adaptation into existing buildings and flexible program space; the use of effective daylighting; and the provisions to manage passive air handling; the thesis identified what conservational attributes are present and how often these functions are accomplished within the atrium designs of the selected study group of buildings. Overall it was found that the current trends of conservationism in atria of the studied academic buildings are constant, that is, they do not exhibit growth proportional to the increasing awareness of ‘green’ and sustainable thinking seen in today’s culture. Furthermore, the thesis closes with a concluding critique, providing a discussion surrounding the belief that though the atrium is a possible material and energy conservational tool, much of its success can be attributed to the meticulous planning and holistic approach involved in the execution of successfully resolved atria designs