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Fire Sprinker Systems Essay Research Paper Fire

Fire Sprinker Systems Essay, Research Paper

Fire sprinklers are widely recognized as the single most effective method for fighting the spread of fire in their early stages, before they can cause severe injury to people and damage property. Fire sprinkler systems have had a dramatic influence in the designing of new buildings. Fire sprinkler systems prevent fires from spreading, and contain it to a small area. This has allowed arkatecks the flexibility to design floor plans and not have to worry as much about codes relating to fire safety. A building with a fire sprinkler system is considered to be safer and also more valuable. Insurance premiums are almost cut it half if a sprinkler system is present thus making it an investment that will pay itself off, plus some. The pro totally out way the cons of the decision to install fire sprinklers in a build and it is also starting to become mandatory. The concept of an automatic sprinkler system originated in the 19th century but perfection of it did not come until the 20th century. An automatic sprinkler system is defined as followed: “For fire protection purposes, an integrated system of underground and overhead piping designed in accordance with fire protection engineering standards. The installation include one or more automatic water supplies. The portion of the sprinkler system aboveground is a network of specially sized or hydraulically designed piping installed in a building, structure, or area, generally overhead, and to which sprinklers are attached in a systematic pattern. The valve controlling each system riser is located in the system riser or its supply piping. Each sprinkler riser includes a device for actuating an alarm when the system is in operation. The system is usually activated by heat from a fire and discharges water over the area” (NFPA, 13-6). That definition is taken from Installation of Sprinkler System, which is considered the constitution of sprinkler systems.A chemist by the name of Ambrose Godrey is the first recognized person to patent a sprinkler system in 1723. Godfrey s system consisted of a cask of fire extinguishing liquid, usually water, containing a pewter chamber of gunpowder. The chamber of gunpowder was connected to a system of fuses which ignited the gunpowder, thus exploding the gunpowder and scattering the extinguishing liquid. In 1874 Henry S. Parmelee of New Haven, Connecticut, patented the first practical automatic sprinkler head which consisted of a perforated head containing a valve which was held closed against the water pressure by a heavy spring. The spring was held together by two metal eyes made from a low-fusing material. Parmelee was a pioneer is the field of sprinkler systems and some of his principles are still being used today. The Parmelee automatic sprinkler system was installed with a single riser to feed all floors, with the right size pipe, large enough to supply the greatest number of heads on any floor. Another principle still used today is the use of an alarm bell to tell when the sprinkler system is discharging. The alarm valve consisted of a check valve installed in the main riser with a lever connected to the hinged end of the check valve clapper. When water would flow through the check valve, the clapper would move the lever and set off the alarm. A building with a fire sprinkler system has many benefits and that is why sprinkler systems are so widely accepted. The biggest benefit of all is money. The cost for a sprinkler system in many office and institutional occupancies is about equal to what is spent on carpet and floor coverings. That averages out to between “$1.00 to $1.20 per square foot” (Shepardson). With the investment of a sprinkler system into a newly constructed building, you will gain many benefits. The first, and probably the most important, is the savings on insurance premiums. The International Organization of Standards says that a sprinkled high-rise would pay 47% less for building insurance premiums, and 43% less of insurance on it s contents. In addition to savings on insurance premiums, some sprinkler systems are tax deductible. In a world that revolves around money, you can see how a small investment a sprinkler system could be to attractive. There are plenty of reasons behind the reduces rates. The first and most important fact of all, sprinkler systems save lives. A Boston-based safety group cannot site an instance where more that 2 deaths occurred due to fire in a building with fire sprinklers. That fact alone should be reason enough to put a sprinkler system in because there is nothing more valuable than human life. Another fact is that in the early 1990 s, the average cost of a fire in a building without a sprinkler system was $76,250. On the other hand, a building with a sprinkler system could average out to $29,880 a fire. In 98.6 % of all fire in buildings equipped with sprinkler systems, the sprinklers extinguished or controlled the fire. If a fire is extinguished or controlled to a small area, then less assets will be destroyed, thus making a sprinkler system a “safeguard business income and prevent the loss of customer who might go to another source of supply after a fire” (Bryan, 68). Sprinkler systems also prevent costly downtime and assure continuity of business operation; therefore, making a building more attractive to a possible tenant. Most people believe that a smoke detector provides enough protection but all they are is a warning system. Smoke detectors do nothing to extinguish a growing fire or protect those physically unable to escape on their own, such as the elderly, small children, and the disabled.

There are many misconceptions about sprinkler systems. The first, and most common, the reasoning that is one sprinkler head discharges, they all do. This is totally false because of the way sprinkler heads are designed. In order for a sprinkler head to discharge, the sprinkler head must reach the melting point of the “trigger.” Once the melting point it a achieved, the water is then discharge out of the head and off of the defector, thus spraying water only in that area. In order for every sprinkler head to discharge, every head must reach the melting point. There is a one in sixteen million chance that a head will accidentally discharge, thus making it next to impossible that it will happen. Residential fire are usually controlled with one sprinkler head. “90% of all fire are controlled with six or fewer heads and a study conducted in Australia and New Zealand covering 82 years of automatic sprinkler use found that 82% of the fires which occurred were controlled by two or fewer sprinkler” (*********internet). When a sprinkler system is present in a building, the tactics that the fire department will use, differ than if there was no sprinkler system present. Another unknown fact is that a sprinkler system actually conserves water. A sprinkler system efficiently spreads water over the area of a fire unlike a fireman s hose. When the fire department goes to a fire to extinguish it, they usually try to flood the fire out, thus wasting a majority of the water they use. Quick response sprinklers release 7-24 gallons of water per minute compared to 50-125 galllons per minute by a firehouse. Upon arrival to a fire, a fire fighter should immediately locate, and go to the proper control valve to make sure that: “1. All valves are fully open unless they are tagged for repair. 2. Remain there so that if a valve needs to be shut off, then it can. 3. Remain at the riser until it is sure that there will be no rekindling or any detected extension of fire” (Bryan, 46). The fire departments main role is to make sure that the sprinkler system has ample water supply and pressure. To provide that, a riser must always have a fire department connection which would consist of a 2 +” or 3″ hose line. In situations where water pressure is low, a large fire may put a strain on the supply. If there is not enough pressure coming from the supply, then the sprinkler heads will not achieve their designed spray pattern. Sprinkler systems are becoming more popular in residential houses. 78.3% of the total fire deaths are in residential home fires. The cost of a sprinkler system in a residential house is a lot less then in a commercial building because of the type of pipe that is used. Most residential house are piped with a special type of plastic pipe call chlorinated polyvinyl chloride (CPVC), or copper tubing. Copper is more expensive but lasts longer than any other type of pipe, even black iron which is the most common in commercial buildings. The total cost of a sprinkler system in new residential construction is estimated to be around 1% of the total building cost or about equal to the cost of new carpet. Property losses are 85% less in residences with fire sprinklers compared to those without sprinklers. The combination of automatic sprinklers and early warning systems could reduce over injuries, loss of life, and property damage by at least 50%. Over 200 U.S. communities have residential sprinkler laws. Roughly 100 of these communities are in California. In downtown Fresno or example, there has been fire damage of only $42,000 during a 10-year period in which it s sprinklering law has been in affect. Fire sprinkler systems are starting to get more widely accepted in all types of new construction. Laws are starting to be passed making it mandatory to put sprinkler systems in newly constructed buildings. There has been many large fires that have taken the lives of many people that could have been prevented had there been a sprinkler systems present. As years go on, the cost of installing a sprinkler system will continue to go down because of the development of lost cost pipe and other sprinkler materials. Before the year 2000, sprinkler systems will be standard in a newly constructed buildings and residential homes and will have saved more lives than is actually realized.




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