Fire Fighting Tactics And Practice - Essay Example

Firefighting Tactics Name Course Name and Code Instructor’s Name Date Executive Summary Firefighting is a critical process that demands for extensive understanding and knowledge of the fire service crews. First and foremost, they are always the first people that are tasked with suppressing the fire. Accordingly, their activities either will help in the determination of the cause of the fire or might result into the destruction of this vital evidence. They are called upon to be forensic aware; not to destroy the forensic evidence in the course of their operations. This report discusses how fire service crews are supposed to be forensic aware in their fire suppression activities. Introduction The techniques and tactics adopted in putting out a fire have potential impacts on the forensic evidence. The fire fighting methods employed by the fire fighting personnel in other words can substantially affect the amount of evidence acquired from the fire scene particularly if the fire was started by an arsonist. For this matter, it is important for fire to be forensic aware when putting out a fire, in essence they should be aware that an investigator will come after them to investigate the cause of the fire (Grimwood 57). Forensic awareness demands that the fire fighter must act in a manner that their fire fighting activities does not destroy the evidence, by not doing so, they can potentially destroy the evidence thus making it difficult for the fire investigator to determine the real cause of the fire. This report specifically discuses the potential impact of fire service suppression activities; the fire fighting methods and their effects on post fire scene. Accordingly, the paper will; analyze and critique fire investigation by discussing the conflicts between priorities of the operational environment and the fire investigation function. Fire Suppression Tactics and their Effects on Post Fire Scene Speed and weight of response: this refers to how many appliances, how quickly they will arrive at the fire scene and how many personnel will be on the provided appliances. This is a fundamental firefighting tactic together with rescue services. This tactic is driven by strategic policy (Ward 54). This firefighting method states that the faster the fire fighters get to the fire scene together with appliances as well as the larger the number of the firefighting crew the quicker and easier will the fire be put out (Hephaestus Books 66). In this regard, the forensic evidence will not be destroyed as the fire will be extinguished within its growth stage and before it develops to flashover. The compartment fire development is described as having four stages; the incipient, growth, fully developed and decay stages. The flashover is not a development stage but rather a rapid transition between the growth and fully developed stages (Bryant 17). Important to note, compartment fires does not always follow the idealized fire development stages as described above; the speed at which the fire develops, peak heat release rate and the duration of burning are dependent on the characteristics of the fuel involved and the amount of oxygen available / ventilation profile. The flashover has no concrete definition, however, for it to happen there are various conditions that must be met; it has been established that the flashover will occur when the burning rate exceeds a minimum value and the ventilation factor 0.8 (Vermon 88). Accordingly, the heat release must also exceed the critical value. The minimum temperature for the flashover is 6000 C below the ceiling; the radiant heat flux must be at 20kW/m2 at floor level; minimum ventilation factor; and during the flashover the flames will start emerging from the ventilation openings of the compartment (Rafilson 67). The rate of heat release needed for flashover is usually increased by an increase in the area of ventilation opening; this will increase the amount of oxygen availability thus increasing the rate of burning. An increase in compartment size and an increase in hk that controls the rate of heat loss through the compartment are other factors that will increase the heat release rate required for flashover. The amount of time for pre-flashover is extremely hard to determine or predict, however the following factors will automatically reduce the time to flashover: When the combustible items are tall If the first item ignited is locate in a corner If the fire spread over the items in the compartment is rapid. These three factors ensure that the duration taken for the fire to reach the ceiling of the compartment is substantially reduced. It has been established that when the tip of the flame is around 5500 C, the temperature under the ceiling will be quickly approaching 6000C; the onset of the flashover (Ridenour 89). The increase in temperature of the ceiling combined with upper wall significantly contributes to a radiant heat flux to the lower part of the compartment. Accordingly, flashover needs sufficient heat release rate for the temperature of fuel packages within the compartment to increase significantly thus influencing their ignition and for the fire to quickly transition to the fully developed stage (Murtagh 77). Nonetheless, during fire development within the compartment, the fire will become ventilation controlled whereby the fire growth and heat release rate determined and controlled by the available air. The sufficient heat release rate needed to cause a flashover can substantially be generated in a ventilation-controlled fire. Accordingly, in ventilation controlled state an increase in the ventilation profile will virtually result into an increase in HRR. For instance, this can be caused by fire fighters entering the building, tactical ventilation or failure of glazing. Fire growth together with steady burning in confined space is progressively influenced by the availability of the compartment boundaries (Coleman 73). The availability of sufficient fuel and air supply will cause the fire to develop rapidly to a stage where all combustible surfaces will quickly be involved and thus the fire will progress to maximum density achieving temperatures of up to 10000 C and above. At this point, the fire has the ability to cause structural damage spreading beyond the initial compartment thus destroying all forensic evidence. When the fire is contained during the pre-flashover stage, it is easier to determine the origin and cause of the fire; the forensic evidence has not yet been destroyed (Klinoff 112). Accordingly, containing the fire at this stage, pre-flashover fire patterns are easier to determine than in the post-flashover. As already established above the speed and weight of response is a key factor that will ensure that the fire is contained during its initial stages of growth thus giving the fire investigators an opportunity to investigate and determine the origin and cause of the fire (Ward 43). Use of water: water is one of the predominant media used by firefighting crew to contain fire. Water sprays is considered best under this circumstances as it is less likely to destroy forensic evidence with regard to the origin and cause of the fire (Venue 103). The use of excessive water will impact negatively on the forensic evidence; for instance, the use of too much water will destroy the evidence. In this essence, it is paramount for firefighting crews to avoid using excessive water on smouldering debris. They are advised to spray water gently on to the fire in order to suppress smoke production while at the same time allowing the investigator to carry out thorough investigation and establish the origin and cause of the fire. More water will destroy fire scene evidence. Use of foams including CAFS: this technique involves spraying compressed air foams to suppress the fire. Though it is an effective technique for putting out fire, the foam may contain some components that are likely to interfere with ignitable liquid analysis. For example, these components may have petroleum distillates including kerosene and/or diesel that may have a negative impact on chromatographic analysis. In this regard, if the fire crews used compressed air foams in containing the fire, samples of the compressed air forms should be submitted to the lab together with other evidence collected from the scene in order to determine correctly the cause and origin of the sire. Use of dry agents and chemical additives: these dry agents and chemical additives are also used for fire suppression. However, some of these dry agents and chemical additives might have derivatives of petroleum spirits (Terpak 115). If these dry agents are used, the fire service crews must be aware of the petroleum derivatives. Like in the case of foams, dry agents and chemical additives samples must be taken to the lab together with other evidence collected from the fire scene in order for the fire investigator to determine conclusively the origin and cause of the fire. Tactical ventilation: this is a common method or fire fighting tactic that is used by firefighting personnel to improve the firefighting environment, assists in casualty’s location as well as reducing the heat and smoke damage to the building. Ventilation can be achieved naturally or mechanically be using fans (Positive Pressure Ventilation). This technique can be used in post fire, defensive and offensive modes (Shapiro 64). If this method is not used properly, it can cause fire to develop and spread rapidly in the direction that is inconsistent with what the fire investigator would consider normal. Accordingly, forced ventilation and/or natural ventilation due to fire fighting operations may culminate into changing or altering the fire patterns thus making it hard for the fire investigator to determine and establish the origin and cause of the fire. Similarly, tactical ventilation may result into induced flashover hence causing the fire to develop into fully developed stage. In general, the manner in which the fire service crew ventilates the building will affect the growth of the fire thus interfering with the origin and the cause of the fire; interfere with the forensic evidence at the scene. Similarly, by using the PPV fan that use petrol; for instance the fuel tank of this fan is leaking and the petrol spills over the floor this might falsify the primary cause of the fire. For example, when the fire investigator may be derailed from the real cause of the fire and conclude that the fire was caused by petrol. General issues relating to fire fighting tactics: when the firefighters arrive on the scene of the fire and find broken windows and doors, he/she must relay this information to the fire investigator as this might indicate that the fire was caused by someone (Stowell, IFSTA, and Hieber 76). Similarly, the colour of the flame together with the smell of the smoke must be passed over to the fire investigator. Accordingly, if the fire fighters find a dead body at the fire scene they should not move this body or temper with it as they might interfere with the evidence (Faria 88). In the same line of thinking, if the fire fighter goes to isolate the electricity, he/she should remember to indicate if it was on or off, whether the electric fuse was intact or not as this information should be passed over to the fire investigator. The removal of furniture from the compartment will automatically impair with the forensic evidence at the fire scene (Norman 21). Most importantly, a small number of people should be allowed into the fire compartment during the fire suppression process. There should also be one way or route to be used for entering the fire compartment and coming out in order not to destroy the evidence. Analysis and Critique of Fire Service Operations As already discussed in the above section, mistakes by fire service crews can result into potential destruction of evidence; accordingly, poor organization and coordination of fire service operations at the fire scene often result into more harm than good. For instance, the conflict between the priorities of operational environment and fire investigation function. In such a situation, the fire service crews might compromise the firefighting process by being more forensically aware; not taking decisive actions for the fear of destroying the evidence. Conflicts between priorities of the fire service environment and the fire investigation function can culminate into more harm including death of the firefighting crews together with inhabitants of the building under fire. For example, the Cherry Road Incident, in 1999 two firefighters died while two others were severely injured in America due to being trapped by the rapidly growing fire. The main issues that influenced the death and injury of these firefighters can be traced back to the changes in ventilation profile. For example, the occupants opened windows on the second floor; similarly, they left the front door open when they exited the building, tactical ventilation of the first window together with opening of the sliding glass door in the basement resulted into a ventilation-influenced flashover. Due to this, the four firefighters were trapped in the burning building of which two died while two were severely injured. Conclusion The above discussion provides a clear explanation with regard to how fire service crews are supposed to conduct themselves when suppressing fire regardless of the method or tactic they use. For instance, they are called upon to be forensically aware; the fire investigator will come after them to determine and establish the origin and cause of the fire. The main fire suppression tactics include: the speed and weight of response, the use of water, the use of foams like CAFS, dry agents and chemical additives, tactical ventilation, and other general issues related to firefighti9ng tactics. Whenever the fire service crews use these methods they should be forensic conscious lest they destroy the evidence and make it hard for fire investigators to determine the real cause of the fire. Important to mention, the conflict between the priorities of the operational environment and the fire investigation function can result into incidences of death and extreme injuries to the fire service crews as well as the occupants of the building. Works Cited Bryant, Ginger. Orlando Firefighting. London: Arcadia Publishing, 2008. Print. Coleman, John. Incident Management for the Street-Smart Fire Officer. London: Fire Engineering Books, 2008. Print. DeHaan JD, and Icove DJ. Kirks Fire investigation, 7th Ed. Upper Saddle River, NJ: Pearson Education, 2011. Print. Faria, Toni. Burlington Firefighting. New York: Arcadia Publishing, 2008. Print. Grimwood, Paul. Euro Firefighter. New Jersey: Jeremy Mills Publishing, 2008. Print. Hephaestus Books. Articles on Fire Suppression, Including: Fire Sprinkler System, Standpipe (Firefighting), Fire Sprinkler, Gaseous Fire Suppression, Dry Riser, Fire Pu. London: Hephaestus Books, 2011. Print. Klinoff, Robert. Introduction to Fire Protection, 4th ed. London: Cengage Learning, 2011. Print. Murtagh, James. Barron's Firefighter Exams. London: Barron's Educational Series, 2009. Print. Norman, John. Fire Officer's Handbook of Tactics. London: Fire Engineering Books, 2012. Print. Rafilson, Fred. Master The Firefighter Exam: Targeting Test Prep to Jump-Start Your Career. London: Peterson's, 2008. Print. Ridenour, Marilyn. Leading Recommendations for Preventing Fire Fighter Fatalities, 1998-2005. London: DIANE Publishing, 2010. Print. Shapiro, Larry. Fighting Fire: Trucks, Tools and Tactics. Manchester: MotorBooks International, 2008. Print. Stowell Fred, IFSTA, and Hieber Libby. Structural Fire Fighting: Initial Response Strategy and Tactics. California: Pearson Education, Limited, 2011. Print. Terpak, Michael. Assessment Centre Strategy and Tactics. New York: Fire Engineering Books, 2008. Print. Venue, Catherine. A Guide to Wildland Firefighting Including Tactics, Equipment, Personnel, Wildfire Disasters, and More. New York: Webster's Digital Services, 2012. Print. Vermon, Laura. A Closer Look Into Wildland Firefighting. New York: Webster's Digital Services, 2012. Print. Ward, Leroy. Army Fire Fighting: A Historical Perspective. London: AuthorHouse, 2012. Print. Read More

An increase in compartment size and an increase in hk that controls the rate of heat loss through the compartment are other factors that will increase the heat release rate required for flashover. The amount of time for pre-flashover is extremely hard to determine or predict, however the following factors will automatically reduce the time to flashover: When the combustible items are tall If the first item ignited is locate in a corner If the fire spread over the items in the compartment is rapid.

These three factors ensure that the duration taken for the fire to reach the ceiling of the compartment is substantially reduced. It has been established that when the tip of the flame is around 5500 C, the temperature under the ceiling will be quickly approaching 6000C; the onset of the flashover (Ridenour 89). The increase in temperature of the ceiling combined with upper wall significantly contributes to a radiant heat flux to the lower part of the compartment. Accordingly, flashover needs sufficient heat release rate for the temperature of fuel packages within the compartment to increase significantly thus influencing their ignition and for the fire to quickly transition to the fully developed stage (Murtagh 77).

Nonetheless, during fire development within the compartment, the fire will become ventilation controlled whereby the fire growth and heat release rate determined and controlled by the available air. The sufficient heat release rate needed to cause a flashover can substantially be generated in a ventilation-controlled fire. Accordingly, in ventilation controlled state an increase in the ventilation profile will virtually result into an increase in HRR. For instance, this can be caused by fire fighters entering the building, tactical ventilation or failure of glazing.

Fire growth together with steady burning in confined space is progressively influenced by the availability of the compartment boundaries (Coleman 73). The availability of sufficient fuel and air supply will cause the fire to develop rapidly to a stage where all combustible surfaces will quickly be involved and thus the fire will progress to maximum density achieving temperatures of up to 10000 C and above. At this point, the fire has the ability to cause structural damage spreading beyond the initial compartment thus destroying all forensic evidence.

When the fire is contained during the pre-flashover stage, it is easier to determine the origin and cause of the fire; the forensic evidence has not yet been destroyed (Klinoff 112). Accordingly, containing the fire at this stage, pre-flashover fire patterns are easier to determine than in the post-flashover. As already established above the speed and weight of response is a key factor that will ensure that the fire is contained during its initial stages of growth thus giving the fire investigators an opportunity to investigate and determine the origin and cause of the fire (Ward 43).

Use of water: water is one of the predominant media used by firefighting crew to contain fire. Water sprays is considered best under this circumstances as it is less likely to destroy forensic evidence with regard to the origin and cause of the fire (Venue 103). The use of excessive water will impact negatively on the forensic evidence; for instance, the use of too much water will destroy the evidence. In this essence, it is paramount for firefighting crews to avoid using excessive water on smouldering debris.

They are advised to spray water gently on to the fire in order to suppress smoke production while at the same time allowing the investigator to carry out thorough investigation and establish the origin and cause of the fire. More water will destroy fire scene evidence. Use of foams including CAFS: this technique involves spraying compressed air foams to suppress the fire. Though it is an effective technique for putting out fire, the foam may contain some components that are likely to interfere with ignitable liquid analysis.

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