Fires in Buildings - Assignment Example

Fires in buildings: Case studies of four different scenarios Fires occur in almost all kind of buildings, which could happen to be high-rise buildings, commercial premises such as retail shops and factories, and homes, or any building irrespective of the design or material of construction. Whichever the case, all fires fall under four main category namely class A fires, class B fires, class C fires, class D fires. Class A fires are caused by solid organic materials such as paper, cloth, wood, plastics or rubber. On the other hand, class B fires are as a result of flammable liquids which are mostly petroleum products while class C fires are related with electricity. Fires resulting form flammable metals like sodium, aluminum, titanium and magnesium are grouped as class D fires. Fires are a menace and throughout history they have been responsible for the loss of many lives and destruction of properties. Therefore, fire occurrences are important in any part of the world and safety measures should be designed to curb outbreak of fires. This discourse will entail an analysis of the 2005 Windsor Tower fire in Spain, the fire that gutted the World Trade Center during the 9/11 terrorist attack, the Manezh Hall fire in Russia and the 2002 Cowgate fire in Scotland. The Madrid’s Windsor Tower fire of 2005 The Windsor Tower also known as the Torre Windsor or Edificio Windsor was a concrete 32-floor building that collapsed after a fire broke out on the 12th of February 2005 in Madrid, Spain. A heavily concrete reinforced building, the Edificio Windsor failed to withstand an apparently class C fire. However, it is worth to note that the actual cause of the fire has not yet been established due to the fact that the “break-out floor” collapsed (University of Manchester). The fire begun at about 23:00 hours at the 21st floor, and spread upwards to all the other floors within a period of one hour then begun spreading gradually downwards up to the third floor. It lasted about eighteen to twenty hours before it was put under control. The entire building was burnt to the extent that it could not be repaired. Fig. 1: South-west view showing the situation of the collapsing Windsor towers (University of Manchester) There are several factors that led to the rapid spread of the fire in building floors. Besides the use of ineffective measures for fire fighting, the floors design contributed a great deal; they were open with an area of about one thousand square meters. In addition, effective measures for vertical sectioning in floor openings and the façade system measures were lacking. According to National Institute for Land and Infrastructure Management (2005), the corroding effects of the fire coupled with the crumpling of the bare steel perimeter in numerous floors allowed for the floors slabs on top of the seventeenth floor to collapse. It is worth to note that floors below the seventeenth floor were protected with fire proof material and after the fire they did not collapse. However, the ninth and fifteenth floor, which had not been protected buckled, but did not result to structural collapse of the floors. The concrete reinforced columns, central core, transfer constructions and waffle slabs stood this severe fire. Furthermore, the structural integrity the building gave it the general stability. World Trade Center September 9/11 fire On September 11, 2001, the World Trade Centre (WTC) twin towers collapsed suddenly after an airplane attack by terrorists that also initiated a fierce fire. It is widely believed that the 9/11 World Trade Center collapse was caused by the melting of the steel by the severe fire (Bazant and Zhou, 2001). The fire was largely composed of the jet fuel and some reports (Clifton, 2001) indicate that aluminum combustion may have accelerated and increased the temperature of the fire. Aluminum can be ignited in special circumstances but this hydrocarbon-based fire may not been a suitable condition for aluminum ignition. Moreover, hydrocarbon combustion in open air can hardly produce a temperature sufficient to melt steel (Eagar and Musso, 2001). Even though the fire did not melt the steel it is substantial to indicate that the fire contributed largely to the collapse of the twin towers. The fire obviously softened the steel structures of the World Trade Center towers. The black smoke that engulfed the building implies that the fire was rich in fuel, a mainly class B fire. It is possible, therefore, that it produced a temperature sufficient to soften the steel in the twin tower; steel starts to soften at 425 ºC (Drysdale, 1985) and factors such as the volume of the flame and the soot quantity highlight that the fire might have attained a temperature as high as 1000 ºC. The fire temperature together with the unequal distribution of the fire played a major role in collapse of the building. Fig. 2: Black smoke from the fuel-rich fire from the World Trade Center (Eagar and Musso, 2001) The fire further contributed to the collapse by distorting the steel making up the building. The fire temperature was non-uniformly distributed with the outside temperature being lower than that facing the fire. Since steel undergoes thermal expansion, the temperature resulted to stresses that culminated into deformations in the slim steel and the eventual buckling. Therefore, the failure of the steel structures was a result of strength loss due to high fire temperatures and reduced structural integrity caused by the steel distortion. The Manezh Hall fire On Sunday March 14, 2004, an enormous fire broke out in the Moscow’s historic hall, Manezh Hall. The fire was rated five, a significantly serious fire category. It is believed that the fire was caused by an electrical short circuit (Flynn, 2004), with some sources indicating that an arsonist action might have been the cause of the fire. All in all, the fire resulted to death of two fire brigadier and the collapse of the halls roofing. The Manezh Hall fire spread rapidly throughout the building. The quick burning of the fire was mainly due to the flammable material that comprised the building. The roof and the attic were made up of wood, which in principle, explains the situation of the fire. For instance, attic floor was built of wooden board of forty millimeters thick. Although, the attic was fire-protected, the fire-resistant materials were three-year old (Flynn, 2004) meaning that they could not be relied upon. Fig. 3: The Manezh Hall fire (msnbc, 2004). The Cowgate fire In December 7, 2002 a fire started at Cowgate, an Edinburg street in Scotland. The fire, which emanated from the La Belle Angele nightclub along the street, spread to neighboring buildings, blazing the sky and producing an acrid smoke that engulfed the city. Although the fire did not cause any casualty, it damaged several properties as it spread uncontrollably through the vaults under the South Bridge. The fire resulted to the collapse of several floors of the nightclub. Moreover, the fire blew out the glass windows of the Leisureland complex as it burnt the neighboring buildings. The fire that was substantially large lasted for almost a whole day after proving difficult to extinguish. The fire spread swiftly though the floors of the seven-storey club and across to other buildings. It burnt part of the University of Edinburg as well as the Gilded Balloon and the La Belle Angelle nightclub. The fire was difficult to put out due to the nature of the streets and premises. The streets were narrow while the premises were characterized by a complicated network for the fire fighters to tackle the fire. Fire safety engineering issues Fire safety engineering refers to the use of principle of engineering and science to guard both the environment and the people from the damaging effects of fire. Therefore, issues concerning fire safety engineering address active and passive fire protection, smoke control, building layout and design, fire dynamics, human behavior, and risk analysis as well as the economics. The Windsor Tower’s structural design met the legal requirements as stipulated under the building codes of the Spanish law. In this regard, therefore, when the tower was being constructed, there was no obligation to fire-protect the steelwork nor was sprinkler system necessitated by the law. Consequently, the Windsor Tower designers failed to include these vital fire protection elements, considering the kind of building and the level of occupancy of the tower. In addition, the breach between the floor tabs and the initial cladding was not fire blocked. It is at the time of the fire occurrence that these vulnerabilities were being sealed. Elsewhere, the open design of the floor meant that only floor-to-floor fire compartmentation was possible. Nonetheless, this compartmentation could not be viable due to the fact that fire-stopping was not done. The fire that burnt the La Belle Angelle nightclub on Cowgate Street and that of at Windsor Tower called for building to install sprinkler systems. The International Building Code (2004) stipulates that clubs and restaurants that accommodate more than one hundred people should have a sprinkler system. Moreover, further recommendation points to the avoidance of using materials which are easily flammable. National Institute of Standards and Technology (2004) advices against the use of non-fire-retarded polyurethane foam as well as any material that catch fire easily and cause fire to spread swiftly. Also the use of pyrotechnics effects inside the building are discouraged. The Windsor Tower fire further emphasized on the need to protect steel with passive fire-resisting materials especially in buildings that employ internal mechanism for fighting and responding to fire. Additionally, the World Trade Center scenario approves the significance of structural integrity, sufficient fire-proofing in high-rise buildings as well as the improvements of the existing measures for fire resistance in these buildings. Note that buildings that are taller than 420 feet are required to have fireproofing with greater adhesive forces (IBC, 2007). The occurrences of the Madrid and Cowgate fire raised the concern on accessibility of building in the event of fire. In fire protection engineering, accessibility to the building is very vital. In the Cowgate scenario, accessing the nightclub as well as other building was very difficult due to the narrow street and the arrangement of the building. In addition, the Windsor Tower fire burnt extensively due to lack of access to the fire by the fire fighters. Technology, equipment and manpower are other aspects that are important in fire safety engineering. As noted in the Madrid fire, use of non-effective equipments and lack of technology to access the fire gave the fire leeway to spread with counter. Moreover, enough fire fighters are required for fire fighting. Opinion Fire is very dangerous and can result to both loss of life and damage of properties. The causes of fire are usually difficult to establish especially if it ends up burning completely the entire building. All in all, fires have an origin and measures can be taken to prevent occurrences of fires. It is essential that fire protection measures are put in place in all buildings, more so buildings that are serve the general public. Different building require different fire protection approaches but the following are essential in building designs: use of less flammable materials, use of fire-protection materials to cover steels and other construction material that do not resist fire, and use of sprinkler systems. Use of highly flammable materials such as polyurethane foam should be avoided, especially in buildings that accommodate a lot of people. The emphasis on the number of people is due to the fact that crowded places are difficult to evacuate in the incidence of fire. Also, accessibility of a building and access to the fire are significant in fire fighting. Therefore, fire protection designers should put into consideration these aspects. The fire scenarios also indicate that fighting fire helps in reducing the losses. Although a fire fighting attempt may not prevent a building from being burnt completely, possible spread of the fire to surrounding premises is mitigated. For example, the Cowgate scenario involved several buildings and is attributed to the inaccessibility of the site. Government and law makers ought to formulate policies and laws that address the requirements as outlined by the incidences of fires in various parts of the world. The number people that a building accommodates on a regular basis, the level of occupancy, and the type of building should form the guidelines under which these policies are enforced. It is worth to note that it is better to prevent the occurrence of fire than to deal with an incidence of fire. This is because although fires are put off after a spirited effort, they all end up causing a lot of losses in terms of time, economic and financial resources, and may end up causing death. Recommendations Certain measures can be taken to prevent the occurrences of fire and to reduce the effect of fire. Occurrences of fire can be mitigated by the following approach: avoiding materials that ignite or spread fire easily on the interior design, using fire-resistive material to cover steel on high-rise buildings, and installing fire-protected sprinkler systems in buildings. Elsewhere, fire-stopping is essential between floors as is vertical compartmentation. This is useful in reducing the spread of fire to the surrounding floors. Accessibility, and techniques and technology for fire fighting are other aspects that are of importance in protection from building fires. These factors should not only be adhered to by building designers and constructors but law formulators and enforcers should make sure these factors are addressed by any builder. Conclusion Fire incidences are never anticipated and therefore it is necessary for the people responsible in guarding buildings to put fire as a priority. With reliable fire protection measures in place, it remains for the fire fighter to respond in case of such incidences. There are several causes of fire, of which voluntary ignition is an option. Building that are built within the accepted standards for fire safety engineering References Applied Science, Fire types, viewed on October 6, 2008, Bazant , Z. P. and Zhou, Y 2001, Why Did the World Trade Center Collapse?—Simple Analysis, Journal of Engineering Mechanics ASCE, viewed on November 4, 2008, Clifton, G. C , 2001, Collapse of the World Trade Centers, viewed on November 4, 2008, . Cook County Board 2004, Report of the Cook County Commission on the 17 October 2003 69 West Washington Building Fire. Drysdale, D 1985, An Introduction to Fire Dynamics, Wiley Interscience, New York, Pp. 134 -140. Eagar, T. W. and Musso, C 2001, Why Did the World Trade Center Collapse? Science, Engineering, and Speculation, Jom, Vol 53, No. 2, Pp 8-11. International Building Code 2004, International Code Council, Washington DC. National Institute for Land and Infrastructure Management 2005, Report on the Windsor Building Fire in Madrid, Spain. NFPA 101 2005, Life Safety Code, National Fire Protection Association, Quincy, MA. University of Manchester, The Windsor Tower Fire, Madrid, Viewed on November 4, 2008, Read More