Case Studies in Fire Safety最新文献

Between October 2007 and June 2012, the Belgian Railways Group and its partners built a new railway tunnel under the main runway of Brussels Airport, to unlock the – also enlarged – station from the unidirectional connection that was available at that time. To facilitate evacuation, intervention and rescue in this newly built 4 km long infrastructure of the so-called Diabolo project, we designed an automated fire scenario system which is part of the tunnel’s and station’s safety concept based on EU Directive 2001/16/EC, NFPA 130 and UNECE TRANS/AC.9/9. Furthermore we implemented access control and intrusion detection as part of the complex’ security concept. In this paper we present our design and our experiences of setting up the system. We also present our real “burning” train test, which took place during the commissioning phase of the project and was a unique opportunity to test the system’s response to “a train on fire” entering the tunnel complex.

The time-equivalence method is one way to determine the appropriate fire severity in buildings. One of the input parameters required is the fire load energy density (FLED) and in a deterministic design this is taken to be a fixed value. This paper illustrates the use of a simple Monte Carlo tool that accounts for statistical variations in car energy content as a function of vehicle size to determine probabilistic FLED values for a risk-based calculation approach to the design of car parking buildings. The paper briefly discusses FLED values for car parking buildings that can be found in the literature and results from the Monte Carlo tool suggest that 260 MJ/m² could be used as an appropriate design value in lieu of using a probabilistic approach.

Photovoltaic systems have played a key role over the last decade in the evolution of the electricity sector. In terms of safety design, it’s important to consider that a PV plant constitutes a special system of generation, where the Direct Current (DC) presence results in changes to the technical rules. Moreover, if certain electrical faults occur, the plant is a possible source of fire. Choices regarding the grounding of the generator and its protection devices are fundamental for a design that evaluates fire risk. The subject of the article is the analysis of the relation between electrical phenomena in PV systems and the fire risk related to ensuring appropriate fault detection by the electrical protection system. A description of a grid-connected PV system is followed firstly by a comparison of the design solutions provided by International Standards, and secondly by an analysis of electrical phenomena which may trigger a fire. A study of two existing PV systems, where electrical faults have resulted in fires, is then presented. The study highlights the importance of checking all possible failure modes in a PV system design phase, to assess fire risk in advance. Some guidelines for the mitigation of electrical faults that may result in a fire are finally provided.

The pace of urbanization and industrialization in developing countries is rapidly increasing. Unfortunately, regulatory and private-sector control of hazards has not always kept pace. This work identifies the level of emergency preparedness in chemical industries and evaluates the spatial distribution of hazards using a worst-case release scenario. Consequently, we identified potentially exposed urban communities and evaluated the social perception of a hazard. This research characterizes risk scenarios in a case study of the industrial area in San Luis Potosi, Mexico. Intervention zones of major concern are recognized when deficiencies in emergency preparedness join a poor social perception of hazards in communities that are potentially exposed. The worst-case scenario radii of flammable chemicals range from 425 m to 733 m. Potentially exposed communities have a limited perception of chemical risk and no training in emergency response. Proximity to an industrial area influences communities towards a better recognition of hazards. However, communities far from the industrial area have higher exposure to low preparedness worst-case scenarios for flammable chemicals and have a larger level of vulnerability because of their lack of risk perception.

Fire engineers are in general, aware of their duties under Building legislation. However, they are often unfamiliar of separate duties under Work Health and Safety legislation.

This paper describes an Australian case-study, but one that is presented generally so as to have applicability in those other jurisdictions where similar Work Health and Safety obligations exist.

As society becomes safer, Work Health and Safety has evolved from being solely about the employer–employee relationship, to also impose duties on other participants, such as building designers. Fire engineers are building designers that by the very nature of their work, directly influence the safety of a workplace. Most buildings upon which fire engineering is practiced are workplaces.

Under Building legislation, fire engineers must design to minimum performance requirements. In the process, usually adopting the most cost effective approach and thereby creating economic benefits.

Under Work Health and Safety legislation however, fire engineers have a duty to adopt the highest possible level of precautions, unless it is not reasonably practicable to do so. The reasonably practicable test must follow the hierarchy of controls and consider all relevant matters, the last of which is cost.

Fire engineers that ignore Work Health and Safety duties, intentionally or not, are exposed to claims of negligence.

Fire incidents in Dubai, United Arab Emirates, reported to the Forensic and Mechanical Engineering section of the Dubai Police Forensic Laboratory during 2006–2013 were reviewed. A detailed examination of more than 5000 incidents, representing a wide range of fire types is presented. Statistical comparisons on the type of incident and the cause and origin of the fire have been evaluated. City areas covered by each police station are also identified. The outcomes of the study indicate that more than one third of the total number of incidents involved motor vehicles and these accounted for more than half of all deliberately set fires in Dubai. A further one third of the incidents reviewed were in residential units. Electrical failures were shown to pose the highest risk of accidental fire and the Bur Dubai Police Station was the busiest in terms of fire investigation caseload.

Stage fire protection measures, details differing from one region to another, have been established, codified and enforced throughout the world and have changed little over the past 100 years. Technological advancements in both stagecraft and fire protection systems have led to a need in the theater community to study the current state of theater fire protection requirements. The objective of the study was to assess the level of protection afforded by stage active fire protection measures, as prescribed by the International Building Code (IBC) (2009), NFPA 80 Standard for Fire Doors and Other Opening Protectives (2007) and as implemented in current design practice, in the event of a fire in the stagehouse of a proscenium theater. The study presented herein assesses the effectiveness of each of the fire protection systems required by building codes for proscenium type theaters. The egress study is not part of this study and thus not specifically carried out.

Computational fluid dynamics (CFD) has been utilized to examine fire conditions and to assess the effectiveness of the fire protection systems provided within a stage. The input data including representative theater dimensions, fuel loads, and fire scenarios have been determined by a survey of theater design professionals.

Life safety is one of the objectives of fire engineering design for road tunnels. Fire engineering design requires maintaining a tenable condition for a period of time to allow occupants to evacuate to safety. This will be achieved by controlling the smoke under credible design fire scenarios in a tunnel. The critical location in a tunnel fire emergency condition is the tunnel region upstream of the fire, where occupants are most likely to reside as traffic jam can usually be created by the fire incident. Tenability for the downstream region of fire is not the main focus of this research because vehicles can generally drive out of the tunnel at a higher speed than that of the smoke flow, and local damper smoke extraction can help keep a tenable condition in the downstream region beyond the local fire zone, in case there is a congestion in the downstream region of the fire.

To maintain a tenable condition in the upstream tunnel region from the fire incident, the required minimum longitudinal flow velocity to prevent smoke backlayering can be calculated based on NFPA 502 recommendations. This critical velocity takes no credit of the smoke extraction or active overhead fixed fire suppression effects.

Smoke extraction with a dedicated smoke duct along the entire length of the tunnel is gaining popularity because of its efficiency and robustness in providing a tenable environment in the tunnel with unknown upstream and downstream traffic conditions. In this paper, a modified critical velocity to control smoke back-layering while smoke extraction and fire suppression systems are operating has been analyzed. This modified critical velocity is approximately 20% lower than the critical velocity that is recommended in NFPA 502. This allows significant savings on ventilation capacity for road tunnels which have a local smoke exhaust capability using a dedicated smoke duct.

It is concluded that the smoke extraction performance is similar whether using ceiling dampers or vertical wall-mounted dampers for smoke capture to maintain tunnel tenability. However, tunnel gradients play a major role on the modified critical velocity for a nominated design fire and the required smoke extraction rate.

Computational fluid dynamics (CFD) has been employed to reconstruct the burning of solid combustible materials of a house fire in Parkes, New South Wales, Australia. Experiment was conducted in a compartment room containing multiple combustible materials with an identified ignition source. Large scale fire development involving the spread of flame and smoke leading to the untenable condition of flashover was observed from on-site visualisations as well as comparison to calculated heat release rates. Significant transient fire events taken from experimental footages including the spread of flame on furniture such as couch and carpet were captured through the numerical model. The present simulation and experimental studies are currently being utilised as components for online fire training program for fire-fighters.

Fire safety engineering (FSE) has become widely accepted throughout the world. This is quite an accomplishment for a young engineering discipline. Fire safety engineers are employed by public and private sector organizations of all types. We are involved in almost all major building and infrastructure projects, enabling amazing buildings to be designed, constructed and occupied. We play critical roles in high hazard industries, helping to mitigate risks and achieve acceptable levels of safety. We undertake groundbreaking research and develop new technologies aimed at reducing the impacts of unwanted fire. However, as an engineering discipline, we lack several attributes that one might expect to see in a mature discipline, including a robust analytical engineering framework. We have not experienced any transformational changes in technology or practice in some time. FSE degree programs and recognition of FSE as a unique discipline remain lacking in several countries, leading to wide variation in the level and consistency of fire safety performance delivered. This has unfortunately led some to question the competency and the efficacy of the profession, in some cases resulting in more regulatory control over the fire safety engineering analysis and design of buildings. The net result is that we are at a crossroad. We face some significant challenges, but we have the opportunity to shape an amazing future. If we are up to the challenges and take advantage of the opportunities, we have a chance to evolve the discipline towards maturity and greater respect. In this article I outline my view of the current situations, some of the challenges we face, steps we might take to overcome them, and areas for research, development and implementation into practice concepts that can lead to a promising future.