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This paper presents frequency reconfigurability of a microstrip patch antenna using a nickel-titanium (Ni-Ti) shape memory alloy (SMA). It comprises a radiating patch made up of Ni-Ti SMA. It is characterized by differential scanning calorimetry, four-probe method and x-ray diffraction in order to evaluate transformation temperatures, electrical resistivity and different phases present in the material, respectively. Currently, a fire sprinkler system consists of a “wet alloy” which will expand when heated initially and then breaks allowing water to sprinkle onto the fire. The present work uses a two-way Ni-Ti SMA which is used to actuate the fire sprinkler system, triggers a sound alarm and is also able to send a message via SMS to the administrator. A microstrip patch antenna is designed, fabricated and measured for reflection coefficient, radiation pattern, and antenna gain at flat and bent configurations. The antenna operates at 2.4 GHz in the flat condition and 3.8 GHz in the bent configuration. This patch antenna can be used in fire alarms which actuate at 66°C and stop the fire without causing much damage. Unlike a conventional fire alarm system, proposed fire sprinkler designed with a Ni-Ti SMA can be reused several times.

A simulation on fire dynamic development is needed to see how fire hazard of a building compartment, particularly in a multistory building. The fire development is affected by fire load content, passive (geometry and building openings) and active (detection, alarm and fire sprinkler) system arrangements. This paper discusses fire hazard of a compartment in a multistory building Rusunami in Indonesia. CFD-Fire Dynamic Simulator (FDS) is used for simulation. Fire load content is modelled by using mattress and wardrobe materials. Room layout is based on the built Rusunami. The results show that continuity of fire is affected by air flow through building openings. With less oxygen, at 390 seconds fire develops to produce maximum temperature of 150 o C, at 408 seconds fractional effective dose (FED) of toxic gases reach incapacitate of 0.5 and accumulation such gases significantly increased. At rich oxygen condition, the time needed from ignited stage until critical temperature is around 486 seconds, and after that in 48 seconds flash over occurred suddenly. This data will then be used as available safe egress time (ASET) to check the fulfillment of performance based fire protection approach in a building compartment.

Accurate representation of the fire sprinkler spray enables quantitative engineering analysis of fire suppression performance. Increasingly, fire sprinkler systems are analyzed with computational fluid dynamics (CFD) fire models where the sprinkler spray is simulated with Lagrangian particles dispersed throughout the fire induced flow. However, there is limited guidance for representing the complex, spatio-stochastic characteristics of the initial sprinkler sprays in terms of these Lagrangian particles. The present work establishes a descriptive analytical framework for the initial sprinkler spray that is rigorously grounded in statistical theory, related to local spray properties, and capable of translating high-fidelity measurements into CFD inputs. This framework describes the initial sprinkler spray as a unified probability distribution function, varying over an initialization surface, and statistically representing measurements of near field local spray properties (volume flux, drop size distribution, and drop size–velocity correlation). Lagrangian particles accurately representing the sprinkler spray may be initialized by a stochastic sampling of this probability distribution function. This novel representation enables high-fidelity initialization of the sprinkler spray in CFD fire models, improving their utility in quantitative engineering analysis.

It is well understood from past earthquakes and experimental studies that non-structural systems suffer more damage and sustain greater losses when compared to structural members. Also, recent years have witnessed significant progress in analytical simulation of non-structural systems. Among these non-structural systems, acoustical lay-in suspended ceilings, fire sprinkler piping and light-gauge steel-frame gypsum partition walls were paid more attention as they contributed to the major construction effort inside a building and damage losses during past earthquakes. This state-of-the-art paper aims to make a comprehensive survey on the recent modelling techniques and sketches a vision for future analytical works that can help the community better assess and improve the seismic performance of acoustical lay-in suspended ceilings, fire sprinkler piping and non-structural light-gauge steel-frame gypsum partition walls.

The activation time of a sprinkler has a great impact on the fire growth inside a compartment. The longer time it takes for a sprinkler to activate, the higher the risk of fire to start to spread inside the compartment. In this study, the activation times of off-the-shelf half inch 68°C fire rated pendant sprinklers were assessed through experiments in laboratory settings and eventually best-fit probabilistic curve for the Response Time Index (RTI) were generated from the experimental results. The experiments were conducted in two sets; one set without smoke effect and the other set with smoke effect to determine the activation time and temperature of the sprinkler heads. The data recorded were then used to calculate the RTI and Palisade @ RISK statistical analysis software was used to analyze the best-fit probabilistic curve for the RTIs. It was observed that, average time required for sprinkler to activate was 60 seconds. It was also found that the calculated RTI were within the range of the international sprinkler design guideline. However, the calculated RTI were found to be inconsistent with specified RTI from manufacturer. Based on @ RISK software, the two best-fit RTI probabilistic curve for the two experiments were Gamma and BetaGeneral distribution curve. The probabilistic curves obtained from this work can be used as input for fire in enclosure simulations.

A fire sprinkler system is very important to extinguish fire in the building. The sprinkler system initiates sprinkler discharge if the detection system identifies a developing fire and opens the pre-action valve. However, pre-action fire sprinkler systems mainly installed in the underground parking lot at the apartment complex do not properly operate at fire if the connection type of fire sprinkler systems does not properly installed and operated. This study identified the relationship between fire dispersion & damage and the connection type of water supply in the sprinkler system from many fire cases at the apartment complex in South Korea. In addition, this study also identified the water supply differences and characteristics between South Korea and foreign countries. The main purpose of this study is also to improve the water connection types in the sprinkler system that can reduce the potential failures of pre-action valve operation through electrical signal system. The study also suggests the improvement plan for water connection types in pre-action fire sprinkler system that can minimize potential failure of pre-action fire sprinkler system. The suggestions for revising the fire safe standard in South Korea includes letting the water supply pipe of sprinkler system water inlet connect to the second side of pre-action valve and the water flow device that can minimize potential failure of sprinkler system.

[EN] Fire suppression modeling depends on accurate characterization of the atomization processes of fire sprinklers. Numerical modeling, particularly the volume of fluid (VOF) method, has been applied to understanding the atomization behavior of an idealized sprinkler geometry consisting of a 9.5 mm inner-diameter cylindrical nozzle and a flat, 25.4 mm diameter disk with a liquid flow rate of 0.87 L/s. The simulations have been performed with an OpenFOAM based VOF solver, using the isoAdvector scheme for interfacial reconstruction. The sheet breakup distance and film thickness were calculated and compared with measurements from a previous study. A mesh refinement study identified the sensitivities in the predicted quantities to mesh resolution. This study enables further application of the model to simulation of the fully atomized spray., This work was funded by FM Global as part of the Strategic Research Program for Fire and Suppression Modeling. Drs. Hrv Jasak and Vuko Vukčević of Wikki Ltd. are gratefully acknowledged for their guidance in using the isoAdvector and ghost-fluid-method schemes. For part of the simulations, this research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725

In the early days, hazards of fire were limited to its thermal hazards. With the advancement of civilization, science and industry, the lifestyles of people have changed, including their housing trends, i.e. space, insulation and ventilation, the hazards of other components of the fire has surfaced. Three family members and a niece were found dead inside their airtight, locked house, in a morning by the driver. The pantry area which opened into the living room had evidence of fire. At the autopsy, all four bodies were covered with black soot, but there were no burns in bodies or clothing. The cause of deaths was given as death due to smoke inhalation. The circumstance of the deaths was ascertained as accidental. Even though deaths due to smoke inhalation are rare, with air-conditioning and insulation of houses, the hazards of smoke have increased in Sri Lanka. Therefore, installations of smoke alarms or fire sprinkler systems are recommended to prevent such deaths in the future.

Safety is one of the major concerns of process safety engineers in most industrial facilities all over the world. To this scope, some events play an important role once the effect of their consequences can be assumed as totally undesirable. One of these events refers to the occurrence of a fire. Such event can result in catastrophic consequences for life, equipment, and continuity of activities or even leading to environmental damage. A fire protection equipment with low reliability means that this equipment are often unavailable and thus the risk of a fire increases. Maintenance of fire protection equipment is very important because this kind of systems is mostly in a dormant mode, which gives uncertainty about their operability when demanded in a real situation of fire. This article outlines the importance of tests, inspection, and maintenance operations in the context of a fire sprinkler system and proposes a methodology based on international standards and supported by test/inspection reports to correct the frequency of these actions according to the level of degradation of the components and regarding safety purposes. © 2015 American Institute of Chemical Engineers Process Saf Prog 35: 84–91, 2016

A comprehensive analytical model is developed for a pressurized fire sprinkler piping system of a hospital building. A suite of ninety-six artificial triaxial floor acceleration histories is used to generate seismic fragility parameters of the sprinkler piping system. The analytical model accounts for the inelastic behavior of braces, hangers, and wire restrainers. It incorporates an experimentally validated hysteresis model developed, as part of this study, for the moment-rotation relationship of grooved fitted joints. Component fragility parameters were obtained for lateral restrainers, hangers, and pipe joints. Three system-level damage states were defined based on the level of functionality of fire sprinkler systems and severity of leakage after a seismic event and a joint probabilistic model were utilized to obtain system-level fragility parameters. Finally, the seismic fragility of fire sprinkler systems with grooved fit joints is compared to that of a piping system with threaded joints.

Thousands of sprinkler heads, which have been sampled from in-service sprinkler systems, were tested by Fire Systems Group (FSG) of Industrial & Research Services (IRS) of CSIRO in accordance with the requirements of Australian Standard AS 1851: Part 3 (Maintenance of fire protection equipment - Automatic fire sprinkler systems) and SSL Test Specification FTS-123. During the course of this testing FSG investigated causes of test failures of the sprinkler head samples. The results of these investigations indicated that the main reasons for failure of used sprinkler heads were: adding sodium silicate (“waterglass” or “egg preserver”) to the system in order to overcome small leaks; “intergranular” corrosion of the lead-tin-bismuth “eutectic solder,” which fastens together the two halves of the fusible link; extensive deposit of paint on the deflector and the glass bulb or fusible link; heavy build-up of dirt and debris on the frame, heat-sensitive element and deflector; adhesion of the orifice disc to its seat, due to “glue-like” deposits of corrosion product; and deep deposits of hardened sediment or heavy build-up of water hardness salts above the orifice disc.

In 1996, as part of Waitakere Council’s Water Cycle Strategy, a pressure standardisation programme to permanently lower the average supply pressure citywide was implemented with the aim of reducing water loss and water use. The experience gained during the 1994/95 Auckland water shortage had confirmed that there was considerable scope to reduce pressures in many areas. Since 1996 water pressures have been reduced in over 60% of the reticulated area of the city, with the average pressure reduced from 710 kPa to 540 kPa. As a result of this programme water loss from the network has been reduced, there has been a reduction in the frequency of mains breaks and it is likely that the life of water pipeline assets has been extended. Furthermore both pressure and demand management initiatives have reduced per capita water use in the city by more than 10%. A network computer model was used as a design tool to check the network under various pressure regimes and cost benefit analyses were carried out for various design scenarios. Fire sprinkler systems were checked as part of the design process. Minimum service standards were not reduced and in some cases pressures were actually increased. This paper covers the various aspects of the design, the implementation and the results of the pressure standardisation programme.

This article describes the results of an 18-month collaborative investigation with 30 water purveyors that studied the effects of Class I and Class 2 wet-pipe fire sprinkler systems on drinking water in distribution mains. In water samples taken from a variety of commercial wet-pipe fire sprinkler systems, water quality exceeded the primary standard for lead and cadmium and the secondary standards for iron, manganese, sulfate, color, odor, and total dissolved solids. In field-scale backflow simulations of an average 3-min hydrant-flow test, about 100 gal (0.4 m 3 ) of water backflowed from a wet-pipe fire sprinkler system when the check valve was caused to fail in the open position. The estimated relative risk of being seriously injured in nonresidential fires is 33 times as great as the increased risk of contracting a waterborne illness after backflow has occurred. Retrofitting existing Class 1 and Class 2 wet-pipe fire sprinkler systems that do not currently have backflow prevention assemblies would cost about $4.4-6.0 billion nationwide and was deemed not cost-effective.

This paper considers an extension of the fire field modelling technique to include two-phase fire-sprinkler scenarios—namely the interaction between hot combustion gases and the sprinkler spray. The two techniques currently available to simulate a spray, namely the Lagrangian particle-tracking method and the Eulerian volume-fraction method, are discussed. The mathematical basis of a transient three dimensional computer model based on the latter type is described within this first part.

Editor,—The recent article by Lynne Warda et al did a generally excellent job of reviewing the literature on prevention of fire injuries.1 Perhaps because the keywords did not include “sprinkler”,2 the report completely neglected the tremendous value of automatic fire sprinkler systems in preventing deaths and injuries in house fires. The National Institute of Standards and Technology estimates that while smoke detectors alone can reduce the fire death rate by 52%, sprinklers alone could reduce deaths by 69% and the combination by 82%.3 Sprinklers protect people without requiring human …

A system and method to detect acoustic signals from fire sprinkler heads discharging water and to locate such devices in a public building, airport, sports stadium or other structure which can include a system to measure speech intelligibility. Time and frequency domain analysis are carried out to establish the presence of signals characteristic of water discharge from a fire sprinkler.

Several of the ten production Modules in Building 707 at the Department of Energy Rocky Flats Plant recently underwent an alteration which can adversely affect the performance of the installed automatic fire sprinkler systems. The Modules have an approximate floor to ceiling height of 17.5 ft. The alterations involved removing the drop ceilings in the Modules which had been at a height of 12 ft above the floor. The sprinkler systems were originally installed with the sprinkler heads located below the drop ceiling in accordance with the nationally recognized NFPA 13, Standard for the Installation of Automatic Sprinkler Systems. The ceiling removal affects the sprinkler`s response time and also violates NFPA 13. The scope of this study included evaluation of the feasibility of utilizing heat collectors to reduce the delays in sprinkler response created by the removal of the drop ceilings. The study also includes evaluation of substituting quick response sprinklers for the standard sprinklers currently in place, in combination with a heat collector.

The paper considers the mathematical modelling of compartment fires and the interaction with an activated sprinkler system. Various fire and fire sprinkler models are discussed. Two methods of modelling the spray, namely the Lagrange particle-tracking method and the volume fraction method, are highlighted. The mathematical basis of a computer model, currently under development, is described. The first results obtained with this model are discussed and appear encouraging.

Since the use of the digital computer has become widespread in the engineering profession, numerous papers3 7 9 12 have described computer programs written to solve pipe network problems. Yet despite the advantages of more sophisticated methods, many practicing engineers and recent graduates are still using the Hardy Cross methods introduced for manual computation over 40 years ago. Among the more promising alternatives is the nodal formulation of the matrix equation using the Newton-Raphson first-order approximations to the nonlinear equations that express rate of change of unbalanced flow at each node with respect to change of head at all connected nodes,9 including the node under consideration. Such a digital computer method is well within the intuitive grasp of practicing engineers and certainly within the mathematical comprehension of today's engineering graduates. It provides a more powerful tool than the Hardy Cross nodal method, which neglects the change in flow at each node caused by iterative head corrections at all connected nodes except for the node at which the flow is being calculated. Convergence to a satisfactory solution can be obtained even for very large (1000-node) networks that are poorly interconnected. The program outlined here, written in Fortran IV, G level language, uses this method to solve large-scale networks with supply pumps taking water from wells or reservoirs, booster pumps, pressure-actuated check valves, one-way check valves, pressure-regulating valves, reservoirs of any geometric shape, fire flows superposed on other nodal demands, and sprinkler heads at nodes for golf-course, agricultural, or building fire sprinkler applications. Computer reordering of node numbers minimizes the required matrix computations, and a sparse matrix technique requiring storage only of the off-diagonal non-zero partial derivative elements of the matrix dramatically reduces storage requirements of the matrix equation. The use of disc storage capabilities for all input data and for storage of most calculated variable arrays also greatly reduces central processing unit (cpu) memory storage requirements. Division of the program into three primary element files of subroutines, which may be overlayed in compiling the load module, further reduces memory storage so that large network systems may be solved on relatively small computer installations. A network with up to 1000 nodes, 1400 pipes, 35 supply pumps, 20 booster pumps, 5 regulating valves, 40 sprinkler heads, 10 reservoirs, and 10 fire flows is handled with 35K of cpu memory-about 10 per cent of the requirement for some programs in common use. Finally, by taking full advantage of the relatively large storage capacity provided by disc, which may be easily transferred to tape, the program provides slots for storing up to 25 network problems with their solutions, permitting rapid and easy retrieval of any problem desired, with subsequent deletion, addition, or modification of any network element to define a new problem for a solution starting where the retrieved problem as changed ended. Storing and retrieving data from disc trades off disc input-output (I-O) time against reduced cpu memory requirements. The time required for the disc I-O operations depends upon network size and the number of such special elements as supply pumps, booster pumps, check valves, regulating valves, and sprinkler heads. The time may vary widely among computer systems. On the computer system at Montana State Univ., where the program was developed, the estimated disc I-O times for input, problem solution, and output are 31 s for 35 iterations with a 300-node, 420-pipe network with no special elements and 52 s for a similar network of 500 nodes and 700 pipes. For the latter network with a check valve, a regulating valve, and a supply pump added the estimated time for 35 iterations is 71 s. For the same

The causes of two roof failures are presented, along with interpretations of related code requirements. One roof collapsed as fire sprinkler water accumulated on the ceiling. The second roof collapsed as rain water accumulated behind perimeter scuppers. Examples also are developed to illustrate design procedures for each case.

The subject of water rates and allocating fire protection costs has been a controversial issue for many years. A search of the literature supports this point. There probably is general agreement on the principle that each function of a water system should be charged for the cost of providing that function, but the problem is in determining how to distribute the charges equitably between the various functions. Water systems can be considered to have two primary functionsthe supply of water for general consumption and the supply of water for fire protection. Revenues to support these functions are generally received in the form of charges for readiness or ability to serve and in the form of charges for water actually consumed. Costs for items in a water system, such as meters and treatment facilities, are obviously directly attributable to general consumption costs and should be assigned to this function. Other costs for items, such as hydrants, are obviously directly attributable to fire protection costs and should be assigned to this function. Certain cost items, such as fire sprinkler service connections, are directly attributable to private fire-protection service costs and should be charged to the benefited property owner. Remaining cost items, such as distribution mains and distribution storage facilities, are used jointly for general consumption and fire protection. Determining the most reasonable and equitable method of distributing costs between these two functions is the main point of disagreement among water-utility people, general governments, and fire protection experts.

This petition was denied by the Commission because of the wellestablished fact that the automatic spinkler charge is nothing more nor less than a ready-to-serve charge which is included in the rate schedule of every public utility furnishing electric and water service in the State of Indiana. The principal averment of the petitioners was, that the charge for this water connection imposes an additional burden on the automatic sprinkler owners and is a discriminatory tax; and that it tends to destroy the interest of the average property owner in equipping his property for the reduction of fire peril. Petitioners introduced considerable evidence to show the unreasonableness of the automatic spinkler charge herein complained of, but also set forth the fact that the fire hazard in factories is greatly reduced by the automatic sprinkler system; that properties adjacent to factories having such automatic fire sprinkler systems receive the benefit of additional protection; and that such systems result in benefit to labor by making possible its continuous employment, because of the preservation of the factories so equipped. However, petitioners failed to make reference to the fact that no device has any merit or would be of any benefit whatever without an abundant water supply ready with sufficient pressure to force it wherever and whenever needed. Evidence was also introduced by petitioners to show that inasmuch as very little water is used in this service, no expense is attached to

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