On November 9th, 2011 the students from the International Masters of Science in Fire Safety Engineering (IMFSE) studying in Edinburgh University were invited to attend the 5th FIRESEAT symposium "The Science of Suppression". During this conference, attended by ~85 people, we saw eight different speakers from varying parts of the world discussing topics focus around fire suppression.
The first speaker we had the privilege of seeing was Ronald Alpert. As the Alpert Correlations were among the topics covered in our Fire Dynamics course, we were all excited to hear him speak. Alpert explained how he designed his correlations and revisited them with new experiments. He eagerly stressed his excitement for someone to advance his correlations past the current level in which they are.
The next speaker was Yibing Xin of FM Global. Sprinkler technology was the topic discussed. FM Global is working on being able to affectively model how sprinkler systems work during suppression. By doing so, they are creating a new modeling tool, FireFOAM. This would be a very useful tool because of the expensive costs of having full-scale burns. We recognize the challenges faced in order to create a program such as this, although there is no doubt that it would be a great use to the Fire Protection Community.
Andre Marshall form the University of Maryland was the third speaker of FireSeat. The research Marshall is conducting also focuses around sprinklers. In contrast to Yibing, his research involves quantitatively breaking down the spray pattern of a sprinkler head and analyzing it. The techniques being used by Marshall are nothing short of impressive.
FireSeat at this point made a turn toward the use of water mist sprinkler systems. Louise Jackman of LPCB discussed some research she was conducting. This involved using mist systems in different setting with different variables. All we could conclude from this was that mist systems are temperamental, in which the system requires just the right variables to effectively work.
The next speaker was Stefan Kratzmeir of IFAB. He discussed his research involving the use of water mist systems in tunnels, hiting mist could be effective in mitigating a fire. Our concern with this topic was the interaction between the mist and the ventilation. We felt this concern was not addressed.
The next research area discussed was the use of cryogenic suppression, presented by MichaelDelichatsios of the University of Ulster. He explained the used of cryogenic material (mainly liquid nitrogen) to extinguish pool fires and wood crib fires. Although the method was effective, the delivering of the agent to the seat of the fire seems to remain the issue in which water and foam systems still have over such a suppression agent.
Suppression in tunnels again arose with the next speaker, Elizabeth Blanchard. Her modelling results of fire suppression inside a medium size tunnel seemed to be more accurate than previous studies. But the question already began to loom among our students concerning the interaction between the mist delivered and ventilation. Our concern was again not addressed, despite the effectiveness of the mist system to mitigate fire and enhance visibility, we felt more research should be performed to address the issue.
The final speaker of the 2011 FireSeat was Stefano Chiti of COWI. This research involved using hypoxic air for fire suppression and prevention. This would basically displace oxygen in the combustion process making combustion slow or near impossible to occur. This is a good research area, especially since Halon is no longer being used. We can see the use of this being great as long as it is ensured not to effect human life.
FireSeat was a great experience. It showed suppression research has many different areas that will improve the suppression actions of the Fire Protection Community in the future.
by Joshua Reichert and Oriol Rios, 2011 IMFSE students
Showing posts with label safety. Show all posts
Showing posts with label safety. Show all posts
Thursday, January 19, 2012
Monday, November 28, 2011
2011 Lloyd’s Prize to fire research
Congratulations to Dr Angus Law and co-authors for winning the 2011 Lloyd’s Science of Risk Prize in the Biological/Technological category for their paper on travelling fires for structural design. Dr Law graduated in 2010 with a PhD in Fire Safety Engineering from the University of Edinburgh and now works at Arup. The Science of Risk Prize was launched by Lloyd’s to stimulate cutting edge research into the latest emerging risks facing businesses.
The winning paper is "The Influence of Travelling Fires on a Concrete Frame"
(published in Engineering Structures 33), led by Dr Law and co-authored by Dr Stern-Gottfried, Dr Gillie and Dr Rein. The work argues that the trend towards open plan offices has changed the types of
fire likely to occur in modern buildings. It uses science to look
at ways to improve engineering guidelines and building design, reduce
the risk of travelling fires, and help insurers better quantify and
model fire risk. The presentation given by Dr Law at the award's ceremony built on the concepts of acceptable risk and the margin of error of design methods in the contextt of the engineering duty to use the world’s limited resources as efficiently as possible (see presentation here). The work was founded by BRE Trust and Arup.
Design for infrastructure protection
The winning paper is "The Influence of Travelling Fires on a Concrete Frame"
(published in Engineering Structures 33), led by Dr Law and co-authored by Dr Stern-Gottfried, Dr Gillie and Dr Rein. The work argues that the trend towards open plan offices has changed the types of
fire likely to occur in modern buildings. It uses science to look
at ways to improve engineering guidelines and building design, reduce
the risk of travelling fires, and help insurers better quantify and
model fire risk. The presentation given by Dr Law at the award's ceremony built on the concepts of acceptable risk and the margin of error of design methods in the contextt of the engineering duty to use the world’s limited resources as efficiently as possible (see presentation here). The work was founded by BRE Trust and Arup.Best runner-up
The best runner-up in the same category was our graduate Dr Sung-han Koo for his paper "Sensor-steered fire simulation" (published in Fire Safety Journal and co-authored by Dr J Fraser-Mitchell and Dr S Welch)2010 Awards
This is the second time that Edinburgh recieves the award. Last year Dr Francesco Colella won the 2010 (inaugural) prize in Technology for the paper "A Novel Multiscale Methodology for Simulating Tunnel Ventilation Flows During Fires". And Dr Wolfram Jahn (in Technology) and Dr Claire Belcher (in Natural Hazards) were short-listed within the top five submissions.
Sunday, September 18, 2011
Letter to the Editor of Scientific American
(Email sent on Thur 15 Sep 2011 to editors@sciam.com)
Dear Editor of Scientific American,
Your September issue included the piece "Castles in the Air" by Mark
Lamster where the failed prophecy that the attacks of 9/11 were to end
the age of the skyscraper is discussed.
The article highlights that 2011 will be the single greatest year for
the construction of tall buildings in history. That China is leading the
skyscraper boom, yet their engineering design is dominated by American
firms.
The article discusses design issues on evacuation. But the World Trade
Center was designed to evacuate rapidly, and so both towers WTC1 and 2
did below the impact floors on 9/11. WTC7 was also
evacuated in time.
The article also discusses design issues on aircraft impact. But the World Trade Center was designed to withstand the impact of a large aircraft, and so both towers WTC1 and 2 did on 9/11. They collapsed because of fire. WTC7 was not hit by an aircraft, but collapsed due to fire as well.
The article also discusses design issues on aircraft impact. But the World Trade Center was designed to withstand the impact of a large aircraft, and so both towers WTC1 and 2 did on 9/11. They collapsed because of fire. WTC7 was not hit by an aircraft, but collapsed due to fire as well.
The article goes to imply that the design of tall buildings for
protection against terrorist attacks is mostly about aircraft impact and
evacuation. It does not discuses fire. But WTC 1, 2 and 7 collapsed
because of fire. So they only issue that is not addressed in the article is the one that
brought World Trade Center down, and the one where design advances over
the past decade have been most marginal.
This is a thin favour to fire
engineering and to the safety of tall buildings.
--
*Dr Guillermo Rein*
Senior Lecturer in Mechanical Engineering
University of Edinburgh
http://www.eng.ed.ac.uk/~grein
"so easy it seemed, Once found, which yet unfounded most would have
thought, Impossible!" J Milton
UPDATE Sept 2011: This letter was followed by two more from Dr Bisby and Hilditch
UPDATE Dec 2011: The letter of Dr Bisby has been published in the December 2011 issue of Scientific American.
Friday, July 08, 2011
Call for papers: Fire Technology special issue on WTC Collapse
Fire Technology, the journal of the National Fire Protection Association published by Springer, is preparing an issue on the 2001 fire and collapse of World Trade Center.
The purpose is to collect research, forensic and engineering output of the highest scholarly standards synthesized in the 10 years passed since the event.
Multidisciplinary and international contributions are especially encouraged. Topics of interests include: WTC 1, 2, 5 and 7, the crash, fires, structural response, collapse, forensic conclusions, experiments, modelling, Fire and Rescue intervention, human behaviour, building design, post-collapse fires and recovery, previous attacks on WTC and related subjects.
Submissions will be accepted until 11th Nov 2011 at: http://fire.edmgr.com (choose article type "World Trace Center") .
The call for papers flyer can do downloaded here. Please spread the word, we are looking for a wide range of high quality submissions.
For further information, contact the Associate Editor of this special issue: G.Rein@ed.ac.uk, Dr Guillermo Rein, The University of Edinburgh.
The purpose is to collect research, forensic and engineering output of the highest scholarly standards synthesized in the 10 years passed since the event.
Multidisciplinary and international contributions are especially encouraged. Topics of interests include: WTC 1, 2, 5 and 7, the crash, fires, structural response, collapse, forensic conclusions, experiments, modelling, Fire and Rescue intervention, human behaviour, building design, post-collapse fires and recovery, previous attacks on WTC and related subjects.
Submissions will be accepted until 11th Nov 2011 at: http://fire.edmgr.com (choose article type "World Trace Center") .
The call for papers flyer can do downloaded here. Please spread the word, we are looking for a wide range of high quality submissions.
For further information, contact the Associate Editor of this special issue: G.Rein@ed.ac.uk, Dr Guillermo Rein, The University of Edinburgh.
 |
| A New York City fireman calls for 10 more rescue workers to make their way into the rubble of the World Trade Center. Photo form Wikipedia, United States Navy ID 010914-N-3995K-01 |
Thursday, November 25, 2010
Lloyd’s Science of Risk Prize goes to Fire Technology
Congratulations to Dr Francesco Colella for winning the Lloyd’s Science of Risk Prize in the Technology Category.
The prize was for his research paper "A Novel Multiscale Methodology for Simulating Tunnel Ventilation Flows During Fires" (published in Fire Technology). He led this work as a Research Associate at The School of Engineering from 2007 to 2010.
Dr Richard Ward, CEO of Lloyds told Francesco "The judging panel, comprising experts from academia and insurance felt your paper illustrated how novel computational methods can be used to reduce fire risk in the future. The panel were particularly impressed with how you reduced model run-time by concentrating on what is critical and by coupling fast and slower models".
This is Lloyd’s research prize for academics and aims at keeping the world’s leading specialist insurance market with the pace of academic knowledge and cutting edge thinking.
On top of this winning paper, The University of Edinburgh had three more papers short-listed as the top of each category (two of them from the fire group as well):
* Mr Craig Poland, short-listed in Technology Risk (best runner up), from the School of Medicine for his paper "Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathogenicity" (published in Nature Nanotechnology).
* Dr Wolfran Jahn, short-listed in Technology Risk, from the School of Engineering for his paper "Forecasting Fire Growth using an Inverse Zone Modelling Approach" (published in Fire Safety Journal).
* Dr Claire Belcher, short-listed in Climate Change Risk, from the School of Geosciences for her paper "Increased fire activity at the Triassic/Jurassic boundary in Greenland due to climate-driven floral change" (published in Nature Geoscience).
See related article Hot talent in risk research in the Staff Bulletin of the University of Edinburgh.
See press release by Springer.
Dr Richard Ward, CEO of Lloyds told Francesco "The judging panel, comprising experts from academia and insurance felt your paper illustrated how novel computational methods can be used to reduce fire risk in the future. The panel were particularly impressed with how you reduced model run-time by concentrating on what is critical and by coupling fast and slower models".
This is Lloyd’s research prize for academics and aims at keeping the world’s leading specialist insurance market with the pace of academic knowledge and cutting edge thinking.
On top of this winning paper, The University of Edinburgh had three more papers short-listed as the top of each category (two of them from the fire group as well):
* Mr Craig Poland, short-listed in Technology Risk (best runner up), from the School of Medicine for his paper "Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathogenicity" (published in Nature Nanotechnology).
* Dr Wolfran Jahn, short-listed in Technology Risk, from the School of Engineering for his paper "Forecasting Fire Growth using an Inverse Zone Modelling Approach" (published in Fire Safety Journal).
* Dr Claire Belcher, short-listed in Climate Change Risk, from the School of Geosciences for her paper "Increased fire activity at the Triassic/Jurassic boundary in Greenland due to climate-driven floral change" (published in Nature Geoscience).
See related article Hot talent in risk research in the Staff Bulletin of the University of Edinburgh.
See press release by Springer.
Monday, November 08, 2010
Fire Scholarships from The Lloyd’s Register Educational Trust
New Fire Safety Engineering scholarships from The Lloyd’s Register Educational Trust aim to make buildings safer from fire.
Modern buildings and the people who live and work in them will be better protected from the risk and consequences of fire, thanks to new education and research initiatives within the BRE Centre for Fire Safety Engineering at the University of Edinburgh.
Researchers at the University of Edinburgh are aiming for a better understanding of how contemporary building features – such as lighter construction materials and open-plan interiors – can influence how fires take hold and how fast they spread.
More than £200K in new student scholarships supported by The Lloyd’s Register Educational Trust will help to create a core of leaders who will use new understanding to bring change to the field.
Research and teaching programmes will seek to influence safety planning and design such as building evacuation procedures, fire-safe construction, and guidance for firefighters.
Top-flight undergraduate and postgraduate scholarship students will be recruited to create a cohort of fire safety specialists with expertise in all aspects of modern fire safety techniques.
Three LRET international MSc scholars will be sponsored through a new two-year International MSc in Fire Safety Engineering (IMFSE). The degree, the first multi-institution course of its kind globally, is operated by the Universities of Edinburgh, Lund and Ghent and funded by the European Commission’s Erasmus Mundus programme.
A further six LRET International MEng scholars will be supported in their final two years of the existing degree in Structural and Fire Safety Engineering at the University of Edinburgh.
Dr Luke Bisby, a researcher at the University of Edinburgh’s BRE Centre for Fire Safety Engineering, said: “Building design has changed radically in recent decades – we need a pioneering approach to developing fire safety solutions. We have to ensure that the chances of fire are as low as possible and that if a fire should occur, it will have little chance to spread, everyone inside can be evacuated safely, and economic and environmental losses can be minimised. Only through research linked to innovative educational programs can new approaches to fire safety take hold.”
Michael Franklin, Director of The LRET commented: “The Lloyd’s Register Educational Trust funds exceptional students studying science, engineering and technology throughout the world. We want to encourage and help them to become the future leaders in their chosen field. We hope The LRET scholarships at the University of Edinburgh will help to increase fire safety significantly in the years to come.”
The 2010 winners of the LRET Scholarships are (from left in the photo below):
• Ieuan Rickard, LRET MEng Scholar in Fire Safety Engineering
• Sarah Higginson, LRET MEng Scholar in Fire Safety Engineering
• Eduardo Maciel, LRET International MSc Scholar in Fire Safety Engineering
Congratulations to all three of the winners!
For further information, please contact:
Dr Luke Bisby, School of Engineering, tel 0131 650 5710; email Luke.Bisby@ed.ac.uk.
Notes:
The Lloyd’s Register Educational Trust is an independent charity that was established in 2004. Its principal purpose is to support advances in transportation, science, engineering and technology education, training and research worldwide for the benefit of all. It also funds work that enhances the safety of life and property at sea, on land and in the air.
Modern buildings and the people who live and work in them will be better protected from the risk and consequences of fire, thanks to new education and research initiatives within the BRE Centre for Fire Safety Engineering at the University of Edinburgh.
Researchers at the University of Edinburgh are aiming for a better understanding of how contemporary building features – such as lighter construction materials and open-plan interiors – can influence how fires take hold and how fast they spread.
More than £200K in new student scholarships supported by The Lloyd’s Register Educational Trust will help to create a core of leaders who will use new understanding to bring change to the field.
Research and teaching programmes will seek to influence safety planning and design such as building evacuation procedures, fire-safe construction, and guidance for firefighters.
Top-flight undergraduate and postgraduate scholarship students will be recruited to create a cohort of fire safety specialists with expertise in all aspects of modern fire safety techniques.
Three LRET international MSc scholars will be sponsored through a new two-year International MSc in Fire Safety Engineering (IMFSE). The degree, the first multi-institution course of its kind globally, is operated by the Universities of Edinburgh, Lund and Ghent and funded by the European Commission’s Erasmus Mundus programme.
A further six LRET International MEng scholars will be supported in their final two years of the existing degree in Structural and Fire Safety Engineering at the University of Edinburgh.
Dr Luke Bisby, a researcher at the University of Edinburgh’s BRE Centre for Fire Safety Engineering, said: “Building design has changed radically in recent decades – we need a pioneering approach to developing fire safety solutions. We have to ensure that the chances of fire are as low as possible and that if a fire should occur, it will have little chance to spread, everyone inside can be evacuated safely, and economic and environmental losses can be minimised. Only through research linked to innovative educational programs can new approaches to fire safety take hold.”
Michael Franklin, Director of The LRET commented: “The Lloyd’s Register Educational Trust funds exceptional students studying science, engineering and technology throughout the world. We want to encourage and help them to become the future leaders in their chosen field. We hope The LRET scholarships at the University of Edinburgh will help to increase fire safety significantly in the years to come.”
The 2010 winners of the LRET Scholarships are (from left in the photo below):
• Ieuan Rickard, LRET MEng Scholar in Fire Safety Engineering
• Sarah Higginson, LRET MEng Scholar in Fire Safety Engineering
• Eduardo Maciel, LRET International MSc Scholar in Fire Safety Engineering
Congratulations to all three of the winners!For further information, please contact:
Dr Luke Bisby, School of Engineering, tel 0131 650 5710; email Luke.Bisby@ed.ac.uk.
Notes:
The Lloyd’s Register Educational Trust is an independent charity that was established in 2004. Its principal purpose is to support advances in transportation, science, engineering and technology education, training and research worldwide for the benefit of all. It also funds work that enhances the safety of life and property at sea, on land and in the air.
Sunday, November 07, 2010
A Note on the Philosophy of Engineering Research
Foreword to the PhD Thesis of Dr Cecilia Abecassis Empis.
A Note on the Philosophy of Engineering Research
With the arrival of the computer era came a desperate frenzy of research in all fields with an ever increasing urge to quantify, discretise and explicitly pick apart nature enabling its eloquent description using the languages of mathematics and physics.
This very urge appears to be our largest limitation in attaining a precise representation of nature. Nature is, by nature, a continuum with an infinity that can not be quantified as much in the infinite immensity of the universe’s expanse as in the infinite minuteness into which things can be dissected and in the natural continuum of anything in between, exemplified by the naturally recurring but non-recurrent irrational numbers of Pi, Euler and Fibonacci.
Nevertheless intrinsic to human nature is a desire to group things, categorise, to box knowledge into entities we can comprehend and computers have allowed us to do this more quickly. Part of this process requires an evaluation of what is to be done and what it is to be used for. Be it an equation that represents the physics of electricity, the theories that describe types of intelligence or music that depicts the dance of the bees, the limits of its “accuracy” always lie within the bounds of the assumed scale, an agreement of the axioms of compliance.
Engineering is precisely the art and craft of deciphering such problems. The skill lies in evaluating the scope of the conundrum and identifying the critical players. In outlining the discrete pieces of this puzzle, engineers have to untangle the fundamentals from the peripheral fillers. They then stand back and reason the rules of the game using them to discard unnecessary detail and weave back together the key pieces creating an optimal solution. Engineering is a mere translation tool that allows for the interpretation of nature in a way we can fathom.
It is important however to distinguish a “solution” from “natural reality”. With the computing world fast-appealing to more and more of our senses, it is often tempting to indulge in smaller and smaller dissections of our problems. As we become increasingly obsessed with intricate dependencies we run the risk of creating a solution that is self-fulfilling without realising it has departed so far from its application that it has become a mere representation of the human ego with little or no use beyond the amusement of a select few curious minds. Detail can lead to a false sense of proximity to nature whereas the very nature of engineering is to accept that any attempt to model nature will always fall short of perfect. Instead engineering embraces the asymptotic nature of complex solutions and opts for providing simple and effective shortcuts that are perfect if they solve the particular problem at hand within the scope of its axioms. Hence an engineer must be humble and not lose sight of the problem objectives, the initial assumptions and the scale delineating the limitations and applications of engineering work.
Engineering research aims to provide rational solutions that make daily life just a little bit easier in order to make time for sitting back, relaxing and to enjoy the awesomeness of the irrational, chaotic magnificence of nature.
In this light it is hoped this work will make a useful contribution.
by Cecilia Abecassis Empis
A Note on the Philosophy of Engineering Research
With the arrival of the computer era came a desperate frenzy of research in all fields with an ever increasing urge to quantify, discretise and explicitly pick apart nature enabling its eloquent description using the languages of mathematics and physics.
This very urge appears to be our largest limitation in attaining a precise representation of nature. Nature is, by nature, a continuum with an infinity that can not be quantified as much in the infinite immensity of the universe’s expanse as in the infinite minuteness into which things can be dissected and in the natural continuum of anything in between, exemplified by the naturally recurring but non-recurrent irrational numbers of Pi, Euler and Fibonacci.
Nevertheless intrinsic to human nature is a desire to group things, categorise, to box knowledge into entities we can comprehend and computers have allowed us to do this more quickly. Part of this process requires an evaluation of what is to be done and what it is to be used for. Be it an equation that represents the physics of electricity, the theories that describe types of intelligence or music that depicts the dance of the bees, the limits of its “accuracy” always lie within the bounds of the assumed scale, an agreement of the axioms of compliance.
Engineering is precisely the art and craft of deciphering such problems. The skill lies in evaluating the scope of the conundrum and identifying the critical players. In outlining the discrete pieces of this puzzle, engineers have to untangle the fundamentals from the peripheral fillers. They then stand back and reason the rules of the game using them to discard unnecessary detail and weave back together the key pieces creating an optimal solution. Engineering is a mere translation tool that allows for the interpretation of nature in a way we can fathom.
It is important however to distinguish a “solution” from “natural reality”. With the computing world fast-appealing to more and more of our senses, it is often tempting to indulge in smaller and smaller dissections of our problems. As we become increasingly obsessed with intricate dependencies we run the risk of creating a solution that is self-fulfilling without realising it has departed so far from its application that it has become a mere representation of the human ego with little or no use beyond the amusement of a select few curious minds. Detail can lead to a false sense of proximity to nature whereas the very nature of engineering is to accept that any attempt to model nature will always fall short of perfect. Instead engineering embraces the asymptotic nature of complex solutions and opts for providing simple and effective shortcuts that are perfect if they solve the particular problem at hand within the scope of its axioms. Hence an engineer must be humble and not lose sight of the problem objectives, the initial assumptions and the scale delineating the limitations and applications of engineering work.
Engineering research aims to provide rational solutions that make daily life just a little bit easier in order to make time for sitting back, relaxing and to enjoy the awesomeness of the irrational, chaotic magnificence of nature.
In this light it is hoped this work will make a useful contribution.
by Cecilia Abecassis Empis
Monday, November 01, 2010
Towards the forecast of fire dynamics to assist the emergency response
A recent journal paper titled "Forecasting Fire Growth using an Inverse Zone Modelling Approach" has published in Fire Safety Journal. We are happy that the work has been widely featured in the media and many people is being exposed to the novel idea:
Effective control of a compartment fire saves lives and money. When fire fighters manage to put out a fire before it grows out of proportions, live safety is greatly increased and significant damage can be avoided. Moreover, the affected building can be re-occupied without major investment of resources. But when a fire passes a certain size, the building might collapses as a consequence of the fire damage to the structure (eg, 2001 WTC or 2005 Windsor Tower) or might have to be demolished due to irreversible damages.
Due to a lack of the required technology to support emergency response, fire fighters often have to follow their intuition when it comes to attacking the fire instead of basing their decisions on knowledge of the actual fire. This lack of information can lead to lost opportunities or unnecessary risks.
Prediction of the ongoing fire development ahead of time under different possible conditions based on the current events taking place would give fire fighters insight into the dynamics of the particular fire being flighted. With this extra knowledge, they could weight other options and feed more information into the emergency management. However, fire dynamics follow complex physical processes closely coupled to one another, which makes current tools not able to accurately forecast fire development in real time.
This emerging technology has been called Sensor Assisted Fire Fighting. The FireGrid project, to which this paper belongs together with the recent PhD thesis of the lead author, aims at providing physics-based forecasts of fire development by combining measurements from sensors in the fire compartment with a range of computational modelling tools. The sensor measurements can provide essential lacking information and compensate the accuracy lost, and thus overcome the shortcomings of current modelling tools and speed them up. The proposed methodology is to collect measurements in the fire compartment, and to assimilate this data into the computational model.
When enough measurements are available to characterize the current fire, a forecast is made. This forecast is then constantly updated with new incoming data. If, for example, a door is opened or glazing breaks, and the ventilation conditions change drastically, the sensor measurements will steer the computational model towards capturing the new conditions. With this technology, fire fighters could act upon forecast behaviour.
This paper presents one of the first steps in this direction. Data is assimilated into a simple zone model, and forecasts of the fire development are made. Positive lead times are reported here for the first time. These results are an important step towards the forecast of fire dynamics to assist the emergency response. Together with the application to CFD within the same PhD thesis, the previous thesis of Cowlard on flame spread predictions and the most recent paper by Koo et al. on probabilistic zone models, these establish the basis for technology for sensor assisted fire fighting. The envisioned system is not yet fit for operational purposes and further research is needed. The investigation of the effects of adding further realism in the fire scenarios will be the focus of future studies.
The paper can now be read at the website of Fire Safety Journal.
Note: A related paper is discussed in "FireGrid: An e-infrastructure for next-generation emergency response support"
- Interview for Scottish TV News (go to minute 19 here). Aired on 29 Nov 2010.
- Interview for BBC Radio Scotland (or go minute 42.20 here). Aired on 29 Nov 2010.
- Articles in The Scotsman, CORDIS-EU and Xinhuanet (in Chinese).
Effective control of a compartment fire saves lives and money. When fire fighters manage to put out a fire before it grows out of proportions, live safety is greatly increased and significant damage can be avoided. Moreover, the affected building can be re-occupied without major investment of resources. But when a fire passes a certain size, the building might collapses as a consequence of the fire damage to the structure (eg, 2001 WTC or 2005 Windsor Tower) or might have to be demolished due to irreversible damages.
Due to a lack of the required technology to support emergency response, fire fighters often have to follow their intuition when it comes to attacking the fire instead of basing their decisions on knowledge of the actual fire. This lack of information can lead to lost opportunities or unnecessary risks.
Prediction of the ongoing fire development ahead of time under different possible conditions based on the current events taking place would give fire fighters insight into the dynamics of the particular fire being flighted. With this extra knowledge, they could weight other options and feed more information into the emergency management. However, fire dynamics follow complex physical processes closely coupled to one another, which makes current tools not able to accurately forecast fire development in real time.
Figure: Conceptual representation of the data assimilation process and the sensor
steering of model predictions even when critical events take place in an evolving fire scenario.
steering of model predictions even when critical events take place in an evolving fire scenario.
This emerging technology has been called Sensor Assisted Fire Fighting. The FireGrid project, to which this paper belongs together with the recent PhD thesis of the lead author, aims at providing physics-based forecasts of fire development by combining measurements from sensors in the fire compartment with a range of computational modelling tools. The sensor measurements can provide essential lacking information and compensate the accuracy lost, and thus overcome the shortcomings of current modelling tools and speed them up. The proposed methodology is to collect measurements in the fire compartment, and to assimilate this data into the computational model.
When enough measurements are available to characterize the current fire, a forecast is made. This forecast is then constantly updated with new incoming data. If, for example, a door is opened or glazing breaks, and the ventilation conditions change drastically, the sensor measurements will steer the computational model towards capturing the new conditions. With this technology, fire fighters could act upon forecast behaviour.
This paper presents one of the first steps in this direction. Data is assimilated into a simple zone model, and forecasts of the fire development are made. Positive lead times are reported here for the first time. These results are an important step towards the forecast of fire dynamics to assist the emergency response. Together with the application to CFD within the same PhD thesis, the previous thesis of Cowlard on flame spread predictions and the most recent paper by Koo et al. on probabilistic zone models, these establish the basis for technology for sensor assisted fire fighting. The envisioned system is not yet fit for operational purposes and further research is needed. The investigation of the effects of adding further realism in the fire scenarios will be the focus of future studies.
The paper can now be read at the website of Fire Safety Journal.
Note: A related paper is discussed in "FireGrid: An e-infrastructure for next-generation emergency response support"
Monday, October 18, 2010
A novel methodology for simulating tunnel fires
A recent journal paper titled "A Novel Multiscale Methodology for Simulating Tunnel Ventilation Flows During Fires" has recently been published in the journal Fire Technology. Its content is presented here. This is a joint research effort between Politecnico di Torino and University of Edinburgh.
PD NOTE: This paper won this year’s Lloyd’s Science of Risk Prize in the Technology Category. The prize is awarded to academics and aims to keep the world’s leading specialist insurance market abreast of the latest academic knowledge and cutting-edge thinking. See press release by Springer.
In the past decade over four hundred people worldwide have died as a result of fires in road, rail and metro tunnels. In Europe alone, fires in tunnels have destroyed over a hundred vehicles, brought vital parts of the road network to a standstill - in some instances for years - and have cost the European economy billions of euros. Disasters like the Mont Blanc tunnel fire (1999) and the three Channel Tunnel fires (2008, 2006 and 1996) show that fire poses a serious threat.
Comprehensive risk assessments for tunnel fires are not easy to conduct. The development of the possible emergency scenarios is dependent on the combined influence of fire detection technologies, ventilation system, tunnel layout, atmospheric conditions at the portals and the presence of vehicles. Nowadays, the analysis of such complex phenomena is performed using numerical computational fluid-dynamics (CFD) tools. But CFD has a significant drawback: its requires very large computational resources (e.g., weeks or months of computing time). This limitation affects the completeness of the risk analyses because they can only be based on a limited number of possible scenarios but do not explore the wide range of possible events.
This recent paper proposes a novel multiscale modelling approach generated by coupling a three dimensional CFD model with a simple one-dimensional model. This allows for a more rational use of the computational resources. The methodology has been applied to a modern tunnel of 7 m diameter section and 1.2 km in length (similar layout to the Dartford Tunnels in London). Different ventilation scenarios are investigated involving fire sizes ranging from 10MW to 100MW.
The multiscale model is proved to be as accurate as the traditional time consuming CFD techniques but provides a reduction of two orders of magnitude in the computational time. This greatly widens the number of scenarios that can be efficiently explored. The much lower computational cost is of great engineering value, especially when conducting comprehensive risk analyses, parametric, sensitivity and redundancy studies, required in the design or assessment of ventilation and fire safety systems.
The multiscale methodology is the latest contribution to the state-of-the-art in computational methods for tunnel flow simulations. The model has been validated against experimental data of cold flow ventilation and shown to be accurate. This work was published in Building and Environment in 2009. It has also been used to provide the tunnel operator with a comprehensive assessment of the ventilation in the Dartford Tunnels, located under the River Thames about 15 miles east of London. This work was published in Tunnelling and Underground Space Technology in 2010 (open access version).
PD NOTE: This paper won this year’s Lloyd’s Science of Risk Prize in the Technology Category. The prize is awarded to academics and aims to keep the world’s leading specialist insurance market abreast of the latest academic knowledge and cutting-edge thinking. See press release by Springer.
In the past decade over four hundred people worldwide have died as a result of fires in road, rail and metro tunnels. In Europe alone, fires in tunnels have destroyed over a hundred vehicles, brought vital parts of the road network to a standstill - in some instances for years - and have cost the European economy billions of euros. Disasters like the Mont Blanc tunnel fire (1999) and the three Channel Tunnel fires (2008, 2006 and 1996) show that fire poses a serious threat. Comprehensive risk assessments for tunnel fires are not easy to conduct. The development of the possible emergency scenarios is dependent on the combined influence of fire detection technologies, ventilation system, tunnel layout, atmospheric conditions at the portals and the presence of vehicles. Nowadays, the analysis of such complex phenomena is performed using numerical computational fluid-dynamics (CFD) tools. But CFD has a significant drawback: its requires very large computational resources (e.g., weeks or months of computing time). This limitation affects the completeness of the risk analyses because they can only be based on a limited number of possible scenarios but do not explore the wide range of possible events.
This recent paper proposes a novel multiscale modelling approach generated by coupling a three dimensional CFD model with a simple one-dimensional model. This allows for a more rational use of the computational resources. The methodology has been applied to a modern tunnel of 7 m diameter section and 1.2 km in length (similar layout to the Dartford Tunnels in London). Different ventilation scenarios are investigated involving fire sizes ranging from 10MW to 100MW.
The multiscale model is proved to be as accurate as the traditional time consuming CFD techniques but provides a reduction of two orders of magnitude in the computational time. This greatly widens the number of scenarios that can be efficiently explored. The much lower computational cost is of great engineering value, especially when conducting comprehensive risk analyses, parametric, sensitivity and redundancy studies, required in the design or assessment of ventilation and fire safety systems.
The multiscale methodology is the latest contribution to the state-of-the-art in computational methods for tunnel flow simulations. The model has been validated against experimental data of cold flow ventilation and shown to be accurate. This work was published in Building and Environment in 2009. It has also been used to provide the tunnel operator with a comprehensive assessment of the ventilation in the Dartford Tunnels, located under the River Thames about 15 miles east of London. This work was published in Tunnelling and Underground Space Technology in 2010 (open access version).
Monday, August 16, 2010
"The best part? He is an academic"
Prof Torero is featured in The Times of India and The Bangalore Mirror after he gave the talk "Economics, Fire Safety and Sustainability in the Built Environment: are they Compatible?" at The Indian Institute of Science in Bangalore invited by the British Deputy High Commission Bangalore.Tex from Timesofindia,com:
Professor/investigator plays with fire, literally
BANGALORE: He has participated in investigations into the World Trade Center fires post-terror attacks, Texas City and Buncefield explosions and Madrid Windsor Tower fire. He has also helped design landmark projects like the Nasa space shuttle hangars in Florida, the 80-storey Heron Tower in London and much more. The best part? He is an academic.Professor Jose L Torero delighted an academic audience at IISc during a lecture on Monday as part of the UK-IISc lecture series. He is the BRE/RAE chair in fire-safety engineering, head of the Institute for Infrastructure and Environment, and director of the BRE Centre for Fire Safety Engineering at the University of Edinburgh. Torero spoke on ‘Economics, fire safety and sustainability in the built environment: Are they compatible?'
"Fire safety is a complex problem that encompasses issues as diverse as structural behaviour, toxicology or water management. The specific problems involved require time and length-scale resolutions."
Urban development and accompanying infrastructure, he pointed out, should be designed and maintained in a sustainable way.
"Much effort has been made on understanding energy management, life cycles, environmental sustainability and the economic drivers and deterrents to these policies. In contrast, the role of safety (in specific, fire safety) as a threat to the sustainability of communities has been largely ignored," the professor explained.
MORE ABOUT HIM
Torero's research works were on fire dynamics, flame spread, microgravity research, smouldering combustion, suppression systems and contaminated land among others.
He was elected fellow of the Royal Society of Edinburgh and awarded the Arthur B Guise Medal by the Society of Fire Protection Engineers (USA) in 2008, for recognition of eminent achievement in advancing the science of fire protection.
He is also chair of the Fire & Safety Working Group at the Council on Tall Buildings and Urban Habitat (CTBUH) and vice-chair of the International Association for Fire Safety Science (IAFSS).
Tex from Timesofindia,com:
Tear down a building if you must. Wouldn’t you rather save lives?
Manasi Paresh KumarPosted On Tuesday, August 17, 2010 at 04:59:58 AM
Jose Torero, who was on the investigating team of the WTO collapse and is a consultant to many govts on fire safety, tells us how we can make the city more safe. Two other civil engineers give his global views a local spin
With fire safety now a raging topic, the visit of Jose Torero, professor of fire safety engineering at the University of Edinburgh, to the Indian Institute of Science is timely. Torero who was on the investigating team of World Trade Center collapse, has been a consultant to many governments on fire safety. We engage him in a tete-a-tete along with two other civil engineers from the Association of Consulting Civil Engineers – M S Sudharashan and M U Ashwath – who put his global views in an Indian perspective.
BM: How safe is Bangalore when it comes to fire safety?Jose Torero: Well, I haven’t been around Bangalore that much during this visit so it would be difficult to give a number. But let me put it this way – when technical growth exceeds the city’s ability to respond to it, it will create a problem. This certainly is the case in Bangalore which has a simple history and a very innovative future.
M S Sudharshan: For example, the two tallest buildings in Bangalore, Utility Building and Visvesvaraya Towers, did not have a decent fire exit plan till a few years ago and neither did the city have the expertise to deal with a fire in either of them. Now, with every building competing to be better technically, we are not really sure if we can respond to this demand for better safety facilities. How safe Bangalore really is is anybody’s guess.
Since prevention is better than a cure, how can we plug the loopholes during construction?JT: In an ideal situation, you have a fire safety expert on the panel of engineers when a building is being built. But since that is not possible, the only other way to do it is to ensure that the city administration has the expertise. You have experts to ensure that the building by-laws are followed and another set who do regular checks to ensure they are working. There is no other way.
Ashwath M U: A Carlton Tower could have been avoided if the administration checked repeatedly on safety measures. Now, after the fire department’s NOC (in the case of highrise buildings) you don’t go back to check if they are working after six months. You ask the BBMP or the BDA and they say, they don’t have the expertise to do these checks. The fire department says they don’t have the authority to do these checks. Who then is to be held responsible for the nine people who died in the Carlton fire?
So with no expertise, how do we address this situation? Can international consultants help?JT: First, the city cannot shrug off its responsibility. If you are giving permissions, you better have the ability to check. Second, I don’t think that foreign consultants are the answer because they cannot give you tailormade solutions to local problems. You would only make them richer. Have your inhouse experts to deal with the issue so you can rely on them during the administration’s periodic checks. Third, you currently have the fire department giving NOCs for fire safety. While they need to be involved, they are essentially trained to put out a fire. You need to have an engineering wing to deal with this issue.
AMU: Explain to me how a safety expert from the UK will be able to give you solutions for the cramped quarters of Avenue Road, where commercial activity of every kind takes place.
Talk of implementing the law is all very well but how practical is this solution in the Indian scenario where the builder lobby is so powerful?JT: Well, you need to have the will to change what is wrong. There was a fire in Peru, which killed 600. The situation was worse than what you tell me of your city. It was a disorganised city that had more powerful land mafia. Yet, the government drew up rules to take them on as safety was important.
MSS: If you want to keep your people safe, you need to make decisions. The rules allow the fire safety department to get involved if the building is over 15m tall. What about schools, hospitals or even smaller apartment blocks?
So, the occupancy intent should be the base of fire safety?JT: Absolutely. How can you not bring schools in the gambit? Understand this, everything can be made safer. If the building is old, you can modernise its structure, if the building is new, look into the future. If it absolutely cannot be changed, you have to tear it down. Weigh your options: Who would you rather save – human lives or bricks and mortar?
BM: How safe is Bangalore when it comes to fire safety?Jose Torero: Well, I haven’t been around Bangalore that much during this visit so it would be difficult to give a number. But let me put it this way – when technical growth exceeds the city’s ability to respond to it, it will create a problem. This certainly is the case in Bangalore which has a simple history and a very innovative future.
M S Sudharshan: For example, the two tallest buildings in Bangalore, Utility Building and Visvesvaraya Towers, did not have a decent fire exit plan till a few years ago and neither did the city have the expertise to deal with a fire in either of them. Now, with every building competing to be better technically, we are not really sure if we can respond to this demand for better safety facilities. How safe Bangalore really is is anybody’s guess.
Since prevention is better than a cure, how can we plug the loopholes during construction?JT: In an ideal situation, you have a fire safety expert on the panel of engineers when a building is being built. But since that is not possible, the only other way to do it is to ensure that the city administration has the expertise. You have experts to ensure that the building by-laws are followed and another set who do regular checks to ensure they are working. There is no other way.
Ashwath M U: A Carlton Tower could have been avoided if the administration checked repeatedly on safety measures. Now, after the fire department’s NOC (in the case of highrise buildings) you don’t go back to check if they are working after six months. You ask the BBMP or the BDA and they say, they don’t have the expertise to do these checks. The fire department says they don’t have the authority to do these checks. Who then is to be held responsible for the nine people who died in the Carlton fire?
So with no expertise, how do we address this situation? Can international consultants help?JT: First, the city cannot shrug off its responsibility. If you are giving permissions, you better have the ability to check. Second, I don’t think that foreign consultants are the answer because they cannot give you tailormade solutions to local problems. You would only make them richer. Have your inhouse experts to deal with the issue so you can rely on them during the administration’s periodic checks. Third, you currently have the fire department giving NOCs for fire safety. While they need to be involved, they are essentially trained to put out a fire. You need to have an engineering wing to deal with this issue.
AMU: Explain to me how a safety expert from the UK will be able to give you solutions for the cramped quarters of Avenue Road, where commercial activity of every kind takes place.
Talk of implementing the law is all very well but how practical is this solution in the Indian scenario where the builder lobby is so powerful?JT: Well, you need to have the will to change what is wrong. There was a fire in Peru, which killed 600. The situation was worse than what you tell me of your city. It was a disorganised city that had more powerful land mafia. Yet, the government drew up rules to take them on as safety was important.
MSS: If you want to keep your people safe, you need to make decisions. The rules allow the fire safety department to get involved if the building is over 15m tall. What about schools, hospitals or even smaller apartment blocks?
So, the occupancy intent should be the base of fire safety?JT: Absolutely. How can you not bring schools in the gambit? Understand this, everything can be made safer. If the building is old, you can modernise its structure, if the building is new, look into the future. If it absolutely cannot be changed, you have to tear it down. Weigh your options: Who would you rather save – human lives or bricks and mortar?
Tuesday, July 27, 2010
Starting early with fire experiments
As part of their science education programme the children at Chapter One childcare on Drum Street in Gilmerton spent the morning learning about fire and watching some fire experiments. Dr Stephen Welch from the fire group demonstrated key phenomena governing fire behaviour, i.e. effects of air and water, via the Fire Tornado experiment and an investigation of water suppression of a small pool fire. At the end of the demonstrations all of the children were aware of the possibilities of fire doing unexpected and dangerous things, and they all know that children should NEVER play with fire!
Sunday, July 11, 2010
Prof Torero elected Fellow of the Royal Academy of Engineering
Congratulations to Prof Jose Torero on being elected a Fellow of the Royal Academy of Engineering (FREng). FREngs are UK's leading engineers and a unique national resource.Prof Mike Forde said "This is an incredibly competitive award and reflects Jose's personal engineering achievements related to advances in structural behaviour in fire, material flammibility, tunnel fire safety, contaminant remediation technology and sensor driven emergency response. It also recognises Jose's engineering contributions as an advisor to industry and governments worldwide".
Official announcement can be read here: Academy elects 'unique national resource' to assist in economic recovery, RAEng News Release, 08 July 2010
Friday, June 18, 2010
AXA Fellowship and NFPA Scholarship go to Edinburgh fire researchers
Congratulations to Adam and Jamie!
Dr Adam Cowlard was awarded a 2010 Post-doctoral Fellowships from AXA Research Fund for a proposal to study the burning behaviour of wildland fuels and improve wildfire risk calculations. AXA grants are to "uphold the emergence of the world's scientific leaders".
and
Jamie Stern-Gottfried is the recipient of the 2010 David B. Gratz Scholarship from the National Fire Protection Association in USA. The funds ($5000 USD) are to travel to international conferences overseas and present his thesis work on the role of travelling fires in the structural design of large buildings. This is the fourth Gratz Scholarship that goes to Edinburgh since it was created in 1997.
This scholarship is named for David B. Gratz, the NFPA’s first executive director for international operations, a position he held for 22 years. The scholarship is awarded to recognize the growth of fire science and fire engineering programs. The award was covered by Security Info Watch News.
Dr Adam Cowlard was awarded a 2010 Post-doctoral Fellowships from AXA Research Fund for a proposal to study the burning behaviour of wildland fuels and improve wildfire risk calculations. AXA grants are to "uphold the emergence of the world's scientific leaders".
and
Jamie Stern-Gottfried is the recipient of the 2010 David B. Gratz Scholarship from the National Fire Protection Association in USA. The funds ($5000 USD) are to travel to international conferences overseas and present his thesis work on the role of travelling fires in the structural design of large buildings. This is the fourth Gratz Scholarship that goes to Edinburgh since it was created in 1997.
This scholarship is named for David B. Gratz, the NFPA’s first executive director for international operations, a position he held for 22 years. The scholarship is awarded to recognize the growth of fire science and fire engineering programs. The award was covered by Security Info Watch News.
Friday, April 16, 2010
Congratulations to Dr Abecassis Empis and Dr Jahn for their PhD thesis defenses
Congratulations to the two new Doctors of Philosophy from the fire group!
Cecilia Abecassis Empis successfully defended her PhD thesis on the 23rd of March 2010. The external examiner was Prof. Fred Mowrer from California Polytechnic State University, and the internal was Prof Dougal Drysdale. The thesis title is "Analysis of the Compartment Fire Parameters Influencing the Heat Flux Incident on the Structural Façade" and she was supervised by Prof Jose Torero.
Wolfram Jahn defended his PhD thesis on the 8th of April 2010. The external examiner was Prof Bart Merci from Ghent University, and the internal was Dr Stephen Welch. The thesis title is "Inverse Modelling to Forecast Enclosure Fire Dynamics", and he was supervised by Dr Guillermo Rein and Prof Jose Torero.
Cecilia Abecassis Empis successfully defended her PhD thesis on the 23rd of March 2010. The external examiner was Prof. Fred Mowrer from California Polytechnic State University, and the internal was Prof Dougal Drysdale. The thesis title is "Analysis of the Compartment Fire Parameters Influencing the Heat Flux Incident on the Structural Façade" and she was supervised by Prof Jose Torero.
Wolfram Jahn defended his PhD thesis on the 8th of April 2010. The external examiner was Prof Bart Merci from Ghent University, and the internal was Dr Stephen Welch. The thesis title is "Inverse Modelling to Forecast Enclosure Fire Dynamics", and he was supervised by Dr Guillermo Rein and Prof Jose Torero.
Tuesday, March 09, 2010
April 9, Combustion Phenomena in Fire Science
One-day meeting of the Combustion Institute British Section
Fri Apr 9, Edinburgh
Fri Apr 9, Edinburgh
The Spring meeting of the British Section of the Combustion Institute will be held at the University of Edinburgh, King's Buildings Campus, Daniel Rutherford Building on Friday 9th April 2010. You can find transport and accommodation information in the website.
The on-line registration and payment system is now activated. Fees are£90. Special fees for Students and Retired members £25, and Members of the Combustion Institute/IOP £50. Go to:
http://www.eng.ed.ac.uk/fire/combustion2010
If you are bringing a poster/s as well, send a title and author names to Rory Hadden
*Speakers* Prof Bart Merci, Ghent University, Enclosure fires modelling Prof Dougal Drysale, University of Edinburgh, 2005 Buncefield explosions Dr Savio Vianna, University of Cambridge, Accidental explosions modelling Prof Kai Luo, University of Southampton, Fire suppression modelling Dr Roger Harrison, University of Canterbury, Fire plumes experiments Prof Domingos Viegas, University of Coimbra, Forest fires research Prof John Griffiths, University of Leeds, Lagging fire
Thursday, February 11, 2010
International Master in Fire Safety Engineering still open for European candidates
The SFPE has published a blog reminding that European students can apply to the International Master of Science in Fire Safety Engineering until 15 April 2010.
Apply following this link http://www.imfse.ugent.be
IMFSE is a a two-year MSc program leading to a joint degree between the Universities of Edinburgh (UK), Ghent (Belgium) and Lund (Sweden). It starts in Sept 2010.
The classes in the first semester, covering basic topics in Fire Safety Engineering (FSE), can be attended in Ghent or Edinburgh. All students spend the second semester in Lund, where emphasis lies on enclosure fire dynamics, risk analysis and human behaviour. In the third semester, classes are again taught in Ghent (for general FSE) or Edinburgh (with focus on structural engineering in the context of FSE). The fourth semester is devoted to the Master’s thesis, hosted by one or more of the three institutes.
For questions, visit here or e-mail: IMFSE@UGent.be
Apply following this link http://www.imfse.ugent.be
IMFSE is a a two-year MSc program leading to a joint degree between the Universities of Edinburgh (UK), Ghent (Belgium) and Lund (Sweden). It starts in Sept 2010.
The classes in the first semester, covering basic topics in Fire Safety Engineering (FSE), can be attended in Ghent or Edinburgh. All students spend the second semester in Lund, where emphasis lies on enclosure fire dynamics, risk analysis and human behaviour. In the third semester, classes are again taught in Ghent (for general FSE) or Edinburgh (with focus on structural engineering in the context of FSE). The fourth semester is devoted to the Master’s thesis, hosted by one or more of the three institutes.
For questions, visit here or e-mail: IMFSE@UGent.be
Friday, January 15, 2010
Christmas Tree Fire Safety
This is a fire test of a Christmas tree carried out in our lab. The tree had been in the home of one of our research students for a few weeks over Christmas time. No accelerants were used, this is simply the burning of the tree, ignited by a single candle which was allowed to burn down. The candle burned for 18 uneventful minutes before the start of the video clip.
The peak heat release rate of the fire was about 2.5 MW!
Please be careful with candles on Christmas trees next year!
The peak heat release rate of the fire was about 2.5 MW!
Please be careful with candles on Christmas trees next year!
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