Sprinkler system

Automatic sprinklers have been proven to be the most reliable form of fixed fire protection since their inception 100 years ago. This favorable record allows employers the opportunity to purchase fire insurance at reduced rates if they install sprinklers. Automatic sprinklers are needed anywhere there is a combustible occupancy and where combustible building materials are used. 

The effectiveness of warehouse sprinklers was demonstrated during a February 1998 fire in Lilburn, Georgia. The original warehouse was constructed of brick in 1960 and was fully protected by a sprinkler system. At a later date, a second section was added to the building and was constructed of brick and concrete block. The new section of the warehouse, some 45,000 feet, was not sprinkler equipped. 

A fire started in the new section of the warehouse, apparently by a forklift battery charger. The product stored in the building were rolls of plastic material used to stripe streets and parking lots. The fire devastated the building, warping structural steel and collapsing brick and concrete walls, until it reached the sprinklered portion. 

When the concrete-block fire wall between the two building sections collapsed, the sprinkler system, now nearly forty years old, was triggered. Fifteen sprinkler heads created a water curtain that protected the structure until firefighters arrived. The loss to the unprotected part of the warehouse totaled 1.2 million. 

Sprinkler systems consist of integrated underground and overhead piping systems designed in accordance with fire protection engineering standards. The following are part of the water supply that would feed water through a system to a fire  

Among these active technologies, two measures have been identified for the conception of fire-safe FRP buildings sprinkler systems and internal Hquid coohng systems. In the following sections, each of these methods is described and their potential for imparting fire safety is discussed. 

The functioning of these sprinklers can be initiated by an electronic detection system, or by heat-sensitive valves at each sprinkler head. When a fire is detected, a spray (or more recently, a mist) of water is emitted. The water absorbs the heat of the fire through a phase change to steam and thus arrests the combustion cycle. In certain appHcations where oil fires are expected, such as in restaurant kitchens, a special foam or gel replaces the water in the system. 

The mass transfer coefficient is computed using Equation 3-18 with M0, and K0 for water, that is, 18 and 0.83 cm/s, respectively  

The nonideal mixing factor k ranges between 0.1 and 0.5. Because no information is given about the ventilation, k is used as a parameter. Substituting into Equation 3-14, we obtain 

These concentrations are considerably below the LFL of 1.4% by volume, which illustrates that the specified ventilation rate for Class I liquids is satisfactory for handling relatively large spills of flammable materials. The concentrations do, however, exceed the TLV for this substance. 

Sprinkler systems are an effective way to contain fires. The system consists of an array of sprinkler heads connected to a water supply. The heads are mounted in a high location (usually near ceilings) and disperse a fine spray of water over an area when activated. The heads are activated by a variety of methods. A common approach activates the heads individually by the melting of a fusible link holding a plug in the head assembly. Once activated, the sprinklers cannot be turned off unless the main water supply is stopped. This approach is called a wet pipe system. These systems are used for storage areas, laboratories, control rooms, and small pilot areas. Another approach activates the entire sprinkler array from a common control point. The control point is connected to an array of heat and/or smoke detectors that start the sprinklers when an abnormal condition is detected. If a fire is detected, the entire sprinkler array within an area 

Antifreeze sprinkler system a wet pipe system that contains an antifreeze solution and that is connected to a water supply. 

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The next step is to apply a number of loss control credit factors such as process control (emergency power, cooling, explosion control, emergency shutdown, computer control, inert gas, operating procedures, reactive chemical reviews), material isolation (remote control valves, blowdown, drainage, interlocks) and fire protection (leak detection, buried tanks, fire water supply, sprinkler systems, water curtains, foam, cable protection). The credit factors are combined and appHed to the fire and explosion index value to result in a net index. 

These ahoys are used as fuses, sprinkler system ahoys, foundry pattern ahoys, molds, dies, punches, cores, and mandrels where the low melting ahoy is often melted out of a mold. The ahoys are also used as solders, for the repHcation of human body parts (see Prosthetic devices), and as filler for tube bending. Lead—iadium ahoys are often used to joia metals to glass. 

Chlorinated PVC (CPVC) is used in higher temperature apphcations such as hot-water piping. Because of its superior creep resistance, CPVC is also used in automated fire-safety sprinkler systems. 

The fire death rate in the United States is decreasing, dropping from a rate of 76 per million in the 1940s, when most constmction and decorative products were made of natural materials, to 29 per million in the 1980s, by which time, PVC had replaced natural materials in numerous appHcations (189). This downward trend can be attributed in large part to improved building codes and the broader use of sprinkler systems and smoke detectors. However, the increased use of more fire-resistant materials, such as PVC, deserves part of the credit for this improvement. 

In addition, the copper industry s market development activities have resulted in appHcations such as clad ship hulls, sheathing for offshore platforms, automotive electrical systems including electric vehicles, improved automobde radiators, solar energy, fire sprinkler systems, parts for fusion reactors, semiconductor lead frames, shape memory alloys, and superconducting ceramics (qv) containing copper oxides. 

Started to rise from the reaction, causing the vessel bottom head to fail at the weld seam. The force from the escaping gases propelled the tank into the ceiling and overhead structural steel. A small fire erupted which was quickly brought under control by the automatic sprinkler system. Even though the chemists had reviewed the chemistry and did not anticipate any problems, use testing could have identified this problem in the laboratory rather than the plant. 

Design ventilation system to keep flammable concentration below lower flammable limit Provide on-line flammable gas detection and activation of inerting system Install automatic sprinkler system Install deflagration vents... 

Provide automatic sprinkler system/inerting gas Provide deflagration vents Provide deflagration suppression system Monitor flammable atmosphere/fire Provide nitrogen blocks (nitrogen injection to stop flame propagation) or other explosion isolation measures... 

Provide automatic sprinkler system Use deflagration vents... 

NFPA 13 Installation of Sprinkler Systems, 1996 edition. National Fire Protection Association, Quincy, MA. 

PPO forms one of a group of rigid, heat-resistant, more-or-less selfextinguishing polymers with a good electrical and chemical resistance, low water absorption and very good dimensional stability. This has led to a number of applications in television such as tuner strips, microwave insulation components and transformer housings. The excellent hydrolytic stability has also led to applications in water distribution and water treatment applications such as in pumps, water meters, sprinkler systems and hot water tanks. It is also used in valves of drink vending machines. 

Sprinklers Maintain sprinkler systems Institute alterations if building is modified, use changes etc. Observe use specifications, e.g. for stack heights, fire loading... 

Provide eovered storage, off the ground, away from sprinkler systems, safety showers, overhead water lines or eondensate lines. 

The isolation of certain mechanical equipment, e.g. conveyors, work on lifts, excavations, entry and positioning of cranes, isolation of various safety services , e.g. water or inert gas, stand-by power generation, water supply to sprinkler systems, compressed air for breathing apparatus. 

Termination Have Firefighting Equipment and Procedures, Relief and Sprinkler Systems. 

Siamese connection Sprinkler systems Collecting breeching... 

Sprinkler and water spray installations-Many process and storage area buildings should be protected by automatic sprinkler systems. The size and arrangement for water supply are dependent upon the nature of the hazard and the degree of protection desired. Water spray installations are particularly adapted for cooling uninsulated steel structures, elevated pipe lines, vessels, spheres, and similar plant installations. 

Define areas and buildings to use wet and dry sprinkler systems, foam systems, location of hand and hose fire extinguishers, fire carts, fire engines. 

Coupolet- fittiiigs are uesigned mr us r protection sprinkler systems and other low pressure piping applications. 

An uninsulated 12-ft X 36-ft horizontal storage tank containing CCI4 is to be protected from overpressure due to external fire by means of a rupture disk. The tank does not have a sprinkler system. Storage pressure is 5 psig and should not exceed 10 psig. Tank is assumed to be full, k =... 

Automatic sprinkler systems have the great advantage that they are comparatively simple in concept and operate automatically, whether or not there are people present on the premises. Water is supplied from the public mains or tanks and pumps into a network of distribution pipes at ceiling level, which covers the whole premises. Water is discharged through nozzles or heads sited at regular intervals in the pipework, which are normally sealed with a he at-sensitive device. 

Calculate the relative number of atoms of each element contained in each of the following alloys (a) Wood s metal, which is a low-melting-point alloy used to trigger automatic sprinkler systems and is 12.5% tin, 12.5% cadmium, and 24% lead by mass in bismuth (b) a steel that is 1.75% by mass carbon in iron. 

Arsenic and antimony are metalloids. They have been known in the pure state since ancient times because they are easily obtained from their ores (Fig. 15.3). In the elemental state, they are used primarily in the semiconductor industry and in the lead alloys used as electrodes in storage batteries. Gallium arsenide is used in lasers, including the lasers used in CD players. Metallic bismuth, with its large, weakly bonded atoms, has a low melting point and is used in alloys that serve as fire detectors in sprinkler systems the alloy melts when a fire breaks out nearby, and the sprinkler system is activated. Like ice, solid bismuth is less dense than the liquid. As a result, molten bismuth does not shrink when it solidifies in molds, and so it is used to make low-temperature castings. 

If sprinklers are required, or if the sprinkler system is to be modified, such work should only be performed by a company certified to do it. Fire extinguishers are almost always required. The number of them, their placement, and the types needed are matters to be discussed with fiire officials. Extinguishers should be regularly serviced by qualified specialists. 

The building s sprinkler system, already in place, was extended to the laboratory area by a properly certified contractor. 

The term engineered safety covers the provision in the design of control systems, alarms, trips, pressure-relief devices, automatic shut-down systems, duplication of key equipment services and fire-fighting equipment, sprinkler systems and blast walls, to contain any fire or explosion. 

Sprinkler system Ventilating systems Construction equipment... 

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