Fire Fighting Tactics and Forensic Awareness - Essay Example

Title: Fire fighting tactics and forensic awareness Student Name Tutor Course Institution Date Fire fighting tactics and forensic awareness Introduction Fire fighting has become a very significant profession as the years go by. Countries have put up organizations and departments which help in fire fighting. These organizations employ individuals with fire fighting skills. The fire departments and organization also include experts in forensic analysis. Over the past years, different countries have been faced with the major challenge where their fire fighting crew members lose their lives while working. This unfortunate situation poses a major challenge when getting new employees. Individuals do not want to join the fire fighting departments or organizations in fear of losing their lives. This essay will discuss the fire fighting methods, how they are applied, causes of fire and the fire investigating process. Fire and the Causes of Fire Fire occurs and behaves in different ways but there are three main ways through which this happens. These are flashover, back draught and smoke explosions or fire-gas-ignitions. Flashovers is usually characterized by very high temperatures, flames in the overhead and roll over, smoke layer banks down while back draft is characterized by blue flames in the overhead, high room temperature, pulsating smoke, blackened windows with oily deposits, smoke-layer which constantly rising and falling. Fire is normally classified according to the elements of combustion involved (Grimwood, 2005). Before fire occurs, several factors have to be present. Fire is equal to combustion. Fuel and oxygen are key ingredients in combustion. Fuel varies from home furniture to exteriors like forest, crude oil to gasoline. Types of fuels include liquids, gases and solids which can support combustion. When combustion is taking place, the oxygen that is used can be generated from two sources. First, it can originate from the surrounding air. The percentage of the oxygen will vary up to 20%. When the oxygen concentration is lowered, the combustion will be reduced and ultimately stops. When the oxygen concentration increases, combustion will also increase tremendously. When oxygen saturation occurs on an object, the object will instantly ignite. These sorts of situations usually occur in hospitals and other places where oxygen is used at a greater percentage (Grimwood, Gesmat, 2003). Secondly, another source of oxygen is oxygen that is contained in molecules. In both organic and inorganic peroxides, the oxygen that is found in the molecule can fully sustain the combustion. This situation normally occurs in the effect of gunpowder and fireworks. Fire defined in scientific terms can be explained as exotherm reaction that occurs between fuel and oxygen. The reaction which occurs produces energy and this energy is heat (Lentini, 2012). Other than heat, fire also produces light, soot and other combustion gases like carbon monoxide, carbon and hydrogen. Classes of Fire The main four classes of fire that are mostly known are classes A, B, C, and D. There are additional classes, classes E and F. Class A are fires which occur in ordinary solid combustible materials like paper, mattresses, wood and even bedding. These types of fire are taken care of through cooling the fire through its ignition temperature. Class B is classified as fires which involve flammable liquids like oils, kerosene, tar, gasoline and paints. This class of fires is dealt with through putting a barrier between the burning substance and oxygen. Class C fires include natural gases, butane and propane. When dealing with this kind of fire, the source of the gas must be completely shut down. While putting out the flames, the valves should be reached or else a spark can further cause an explosion. Class D fires include burning metals. These kinds of fires are not very common. The metals include potassium, magnesium, sodium, aluminum, lithium, zirconium and potassium. It is not advisable to extinguish this kind of fire with water because it can end up generating hydrogen gas which is an element for combustion and causes explosion. The best way to extinguish this kind of fire is through using a special extinguishing powder that is based on sodium chloride. Extinguishment can also be done with the use of sand. Class E fires have always been met with a lot of controversy. Experts do not consider it as a class of fire because electric items do not really burn. When dealing with this kind of fire, carbon dioxide or a powder extinguisher is appropriate. Using water in extinguishing the fire is not advised especially when the apparatus is still live. The use of mist or water spray can however be used but with extra caution and care. Class F fires are mostly added and defined for educational reasons. They are also called fat fires. This class of fires should never be extinguished with water. The water sinks, heats up and vaporizes and expanding enormously. Fire fighting tactics The main fire fighting tactics are direct attack, 3D offensive gas cooling, indirect attack and the use of Compressed Air Force (CAFs). Direct Attack In direct attack, the fire fighters enter the building on fire and prepare to attack the fire in an offensive mode where the nozzle man directs the stream at the base of the fire. Direct attack uses a theory which dictates that water is put directly on the base of the fire without disturbing the thermal layer at the ceiling. A straight up nozzle or straight stream are the most appropriate. When the fire has not vented, and water is applied to the base of the fire, the fire will be put off rapidly. This will reduce the steam hence reducing the chances of the fire fighters and victims of experiencing steam burns. Direct attack, prevents the thermal layer from dropping down and harming any trapped individuals this is so because when direct attack is used, the thermal layer will cool slowly and not drop down. Sometimes, the use of direct attack can be quite challenging especially when you are in the room of origin and the fire cannot be seen, a fire fighter should be very careful (Grimwood, 2005). The best tactic to be used is to open the nozzle and aim it high from the floor and sweep the room. This should be done while the nozzle man is kneeling on the floor. This will enable the fire fighter to reach the base of the fire. Indirect Attack In indirect attack, the fire fighters enter the building while preparing to attack the fire in an offensive mode but here the nozzle man directs the stream at the ceiling. This allows the water to rain down on the fire and extinguishing it. When this is done, two situations are most likely to occur. First, the water will cool the ceiling and the thermal layer will be upset which will cause some of the water to vaporize into steam. Secondly, the remaining water will fall like rain to the main body of the fire wall and the fire will be extinguished. Indirect attack should only be used in situations where, the fire office has carefully analyzed the situation and given a go ahead. It should not be used in situations where there are trapped victims because steam can cause severe body burns and even death. Indirect attack should only be used in situations where fire is seen to be venting in the room of origin. This is because the fire fighter will be able to push the heat, smoke and steam out the vent hole which in return will reduce the risk of bun to the fire fighters and the occupants (Grimwood, 2005). Indirect attack will also work when you are preventing a flashover. This is done through controlling a roll over or cooling the area a head of you. This will not extinguish the fire but will prevent other gases from igniting behind you. Compressed Air Force (CAFs) Compressed air force is the new method in extinguishing fire. It is quicker and more efficient. It is mostly used in extinguishing wild land fire. It is also more effective in extinguishing interior fires as compared to water. CAFS is a mixture of three components which are used together in fire extinguishing. The components are water, foam and compressed air. Water is the main component because of its ability to absorb large quantities of heat. The second component is foam solution. Foam used has different types and different mixing ratios. The foam solution is normally added in order to decrease surface tension of water which allows the form structure to be created when combined with compressed air (Grimwood, 2005). This brings us to the third component which is compressed air. Air when combined with the foam solution and water helps in creating the bubble structure which in turn increases the surface area. The main advantages of CAFS which makes it more appropriate in extinguishing fire than water are; quicker and fast break down of fire, lighter hoses that are less tedious and are easier to maneuver. Another advantage is that of the decreased surface tension and increased surface area which allows a blanket of foam which can cover the fuel from oxygen and absorb heat at the same time. This will remove all the three elements that support combustion (heat, oxygen, fuel) and will extinguish the fire immediately. The foam solution can also penetrate in the large piles of fuel which will prevent ignition or re-ignition of fire. 3D offensive gas cooling This new fire fighting tactic was developed by Swedish fire fighters. It is the most recent and innovative approach in fire fighting. This technique uses water fog or fine sprays in extinguishing fires. It is most appropriate in extinguishing all sorts of fire gas ignitions like backdrafts, flashovers and even smoke-gas explosions. It also helps in making a safe approach in fire gas ignited zones. This technique is mostly applied in structural fires (Grimwood, 2005). This technique is not designed to replace the traditional forms of fire fighting tactics like direct and indirect attack but to complement the traditional forms as a way of increasing safety and effectiveness in fire fighting. Before fire fighters employ any tactics, they are supposed to observe other detailed tactical like to deploy resources effectively, briefing the fire crew before getting to the accident scene, confining the fire until a charged hose-line is in place, providing a back-up support hose-line, providing adequate flow-rate at the primary attack nozzle, implementing tactical venting actions in the right place at the right time, undertaking effective search patterns and deviation from documented operating procedure with no good reason (International Maritime Organization, 2001). Before fire fighters get into a burning building or take care of anything on fire, they have to make sure that they are wearing protective gears. These protective gears are called fire-fighting gear. These gears include gloves, outer and under layers, hood, helmet, boots and also breathing apparatus. No firefighter should access a fire building or even training fire. The fire investigation process Fire investigation is the analysis of fire caused or related incidents and accidents. It is also called origin investigation. After the fire has been extinguished by the fire fighters, a fire investigation is launched. This investigation’s main aim is to determine the origin and cause of the fire or explosion. During investigations, fire fighters are supposed to apply their forensic knowledge so that they can easily determine the causes of the fire or explosion (Fraser, Williams, 2013) Before an investigator conducts an investigation, he/she will first receive the assignment, plan for the investigation and gather tools, equipment and people involved, visits the scene in order for him/her to gather evidence and collect data, he then tests, evaluates, analyzes and documents the collected data and finally he applies scientific methods like forensics in analyzing the information gathered (Daeid, 2004). Fire fighters must be comprehensively trained on classes of fire, techniques used in putting out fires and explosions and ways in which they will conduct themselves in a fire or explosion incident. Fire fighters should also know the procedures and ways in which fire and explosive incidents should be followed to the later with no alterations. Safety agencies have been established in many countries all over the world (International Association of Arson Investigators, 2011). In countries like Australia, Sweden and also here in United Kingdom for example, the leading safety agency is Compartment Fire Behavior Training (CFBT). This is a program which has been very effective in reducing life losses and serious burn injuries which most fire fighters suffer during fire and explosion incidents. Fire fighters should always follow the CFBT principles. The principles are currently being adapted into existing training structures together with smoke scrubbers in a mode of purifying the smoke. This helps in purifying the air and lessens the smoke’s effect on the local environment. Conclusion Every fire fighter should have both ordinary and scientific knowledge of fire fighting. They should undergo immense training on what to do and how to do it. They should know all the fire fighting tactics both traditional and the new ones. Fire fighters should have forensic knowledge which can help them in fire investigations. The knowledge and skills will help them in evaluating and analyzing data and evidence that is gathered from fire scenes. While doing their duty on the scene, fire fighters should remember it is not only the safety of the occupants or the victims of the fire or explosion that is important but also their own safety. List of References Daeid, N, N, 2004, Fire Investigation, International Forensic Science and Investigation, Taylor & Francis, London. Fraser, J, Williams, R, 2013, Handbook of Forensic Science, London: Routledge Grimwood, P, Gesmat, K, 2003, Tactical firefighting, Retrieved December 3, 2013, from www.firetactics.com. Grimwood, P, 2005, 3D Fire Fighting: Training, Techniques, and Tactics First Edition, Fire Protection Publications, Oklahoma State University, Oklahoma International Association of Arson Investigators, 2011, Fire Investigator: Principles and Practice to NFPA 921 and 1033, Jones & Bartlett Publishers, Baltimore International Maritime Organization, 2001, Advanced Training in Fire Fighting, IMO Publishing, New York Lentini, J, J, 2012, Scientific Protocols for Fire Investigation, Second Edition, Protocols in Forensic Science, CRC Press, London Read More

Extinguishment can also be done with the use of sand. Class E fires have always been met with a lot of controversy. Experts do not consider it as a class of fire because electric items do not really burn. When dealing with this kind of fire, carbon dioxide or a powder extinguisher is appropriate. Using water in extinguishing the fire is not advised especially when the apparatus is still live. The use of mist or water spray can however be used but with extra caution and care. Class F fires are mostly added and defined for educational reasons.

They are also called fat fires. This class of fires should never be extinguished with water. The water sinks, heats up and vaporizes and expanding enormously. Fire fighting tactics The main fire fighting tactics are direct attack, 3D offensive gas cooling, indirect attack and the use of Compressed Air Force (CAFs). Direct Attack In direct attack, the fire fighters enter the building on fire and prepare to attack the fire in an offensive mode where the nozzle man directs the stream at the base of the fire.

Direct attack uses a theory which dictates that water is put directly on the base of the fire without disturbing the thermal layer at the ceiling. A straight up nozzle or straight stream are the most appropriate. When the fire has not vented, and water is applied to the base of the fire, the fire will be put off rapidly. This will reduce the steam hence reducing the chances of the fire fighters and victims of experiencing steam burns. Direct attack, prevents the thermal layer from dropping down and harming any trapped individuals this is so because when direct attack is used, the thermal layer will cool slowly and not drop down.

Sometimes, the use of direct attack can be quite challenging especially when you are in the room of origin and the fire cannot be seen, a fire fighter should be very careful (Grimwood, 2005). The best tactic to be used is to open the nozzle and aim it high from the floor and sweep the room. This should be done while the nozzle man is kneeling on the floor. This will enable the fire fighter to reach the base of the fire. Indirect Attack In indirect attack, the fire fighters enter the building while preparing to attack the fire in an offensive mode but here the nozzle man directs the stream at the ceiling.

This allows the water to rain down on the fire and extinguishing it. When this is done, two situations are most likely to occur. First, the water will cool the ceiling and the thermal layer will be upset which will cause some of the water to vaporize into steam. Secondly, the remaining water will fall like rain to the main body of the fire wall and the fire will be extinguished. Indirect attack should only be used in situations where, the fire office has carefully analyzed the situation and given a go ahead.

It should not be used in situations where there are trapped victims because steam can cause severe body burns and even death. Indirect attack should only be used in situations where fire is seen to be venting in the room of origin. This is because the fire fighter will be able to push the heat, smoke and steam out the vent hole which in return will reduce the risk of bun to the fire fighters and the occupants (Grimwood, 2005). Indirect attack will also work when you are preventing a flashover.

This is done through controlling a roll over or cooling the area a head of you. This will not extinguish the fire but will prevent other gases from igniting behind you. Compressed Air Force (CAFs) Compressed air force is the new method in extinguishing fire. It is quicker and more efficient. It is mostly used in extinguishing wild land fire. It is also more effective in extinguishing interior fires as compared to water. CAFS is a mixture of three components which are used together in fire extinguishing.

The components are water, foam and compressed air. Water is the main component because of its ability to absorb large quantities of heat. The second component is foam solution.

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