Sprinkler protection of manufactured homes with sloped ceilings using prototype limited water supply sprinklers

Three full-scale fire tests were conducted in a commercial manufactured home 4.3 m wide by 18.3 m long with 10° sloped ceilings. The purpose of the tests was to determine the performance of limited water supply (LWS) sprinklers under a sloped ceiling and to determine whether the minimum distance allowed between sprinklers could be reduced from 2.4 m to 1.8 m. Six prototype LWS sprinklers were installed at a spacing of 1.8 m by 2.4 m in the living room/kitchen area, which measured 4.0 m by 7.2 m. The ceiling and walls were combustible in all three tests, and the room was ventilated by three open windows. The fuel package for all three tests consisted of a vinyl-covered chair with polyurethane padding, double-layered curtains (100% polyester and 50% cotton/50% polyester), and a wooden end table. In the first test, the fuel package was placed in a corner; in the second test, along the wall under the apex of the ceiling between two sprinklers; and in the third test, along the longitudinal wall between two sprinklers. In all tests, no more than two sprinklers actuated. The flow rate with one and two sprinklers operating was 38 pm and 49 pm, respectively. Flow after the first sprinkler actuation was maintained for 10 minutes when one sprinkler actuated and for 7 minutes 40 seconds when two sprinklers actuated. The total flow in each of the three tests was 380. In all three tests, the sprinklers prevented the curtains and wall paneling from becoming involved in the fire during sprinkler operation. Tenability based on carbon monoxide concentration and gas temperature at the 1.5 m level was maintained in all three tests.     

Effect of underreaming on bearing capacity of bored pile

Conclusions 1. From the data for the full-scale static tests of piles 6–22 m long, it was found that as the ratio /d increases, the load transmitted through a pile underreaming having the same size decreases proportionally.2. The limit strength at the foot of piles over 10 m long cannot be determined by means of analytical strengths depending only on the depth h and the liquidity index I_L but which do not depend on the ratio /d.Scientific-Research Institute of Bases and Underground Structures. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 12–14, November–December, 1986.     

Running hot and cold in the urban home-ownership market: The experience of Japan’s major cities

Urban home-ownership in Japan was destabilised when the bubble economy collapsed at the beginning of the 1990s. This paper looks beyond the social and economic changes in Japanese housing in the post-bubble recession to focus on the ups and downs in current home-ownership markets in Japans major cities. Since the mid-1990s, social fragmentation has created a novel environment for urban home-ownership. The combination of a prolonged recession and a policy to promote housing construction and urban redevelopment has split urban space into hot spots, where the housing market is increasingly active, and cold spots, where the market is persistently inactive.     

A strategy for the fire testing of reduced scale structural models

A strategy for the fire testing of reduced scale structural models is developed which takes into consideration all significant thermostructural responses. An investigation of the thermal distributions within a structural element allows fire curve, thermal input and structural displacement output to be linked as cause and effect. Dimensional analysis permits the definition of the conditions necessary for dynamic similarity between model and prototype. An equivalent model fire curve is derived which can be mapped by a simple time scale factor on to a standard fire curve, though distortions due to film effects are noted. Errors due to temperature dependent properties are removed due to the nature of model and prototype temperature distributions. The principles are sensibly validated by low temperature experiments on perspex models of different scales. Finally, it is noted that a model test method would be advantageous for the provision of statistically meaningful amounts of indicative test data, with particular reference to parametric investigations. However, it is recognized that one-off full-scale tests must be conducted to provide the best final assessment of fire resistance.Nomenclature d structural element depth or thickness - d _m ;d _p thickness of model and prototype elements - E elastic modulus - F force on a small element slice - h _f film coefficient - k thermal conductivity - L significant longitudinal dimension or span - L _m ;L _p lengths in model and prototype - q heat flux - s scale factor - t generalized time interval - t _m ;t _p model and prototype test time scales - T generalized temperature - T _e equivalent linear temperature distribution - T _f furnace temperature - T _o average temperature through the thickness - T _x curvelinear temperature distribution - T _w element surface temperature - T ₁ –T ₅ thermocouple temperatures through the thickness - u lateral extension - y lateral displacement or bow - coefficient of linear thermal expansion - thermal diffusivity - T temperature difference over the thickness - slenderness ratio - ₁... _n dimensionless groupings - stress in element - _y material yield stress - () _m reference to model test variables - () _p reference to prototype test variables     

Effects of insulation on postflashover room fire

The effects of insulation on postflashover room fires were studied in a series of full scale room burn tests. Results show that the severity of the fire is not influenced by the presence of insulation in the walls. Reference: K. K. Choi, Effects of Insulation on Postflashover Room Fire,Fire Technology, Vol. 23, No. 1, February 1987, p. 19.K. K. Choi is a fellow of the Society of the Plastics Industry of Canada.     

Postflashover fires — an overview of the research at the national research council of Canada (NRCC), 1970–1985

The NRCC model of fully developed compartment fires is discussed. Although the mathematics involved is quite simple, it allows a rather comprehensive simulation of the fire process. The model offers an explanation for the findings that ventilation control is related to the pyrolysis mechanism and is not a result of scarcity of air in the fire compartment, and that thermal feedback is of secondary importance in the burning (pyrolysis) of cellulosic fuels. Another feature of the model is the introduction of the normalized heat load concept. The normalized heat load is a scalar quantity that depends on the total heat absorbed by the compartment boundaries during the fire incident, and is practically independent of the temperature history of the fire. A simple explicit formula has been proposed and proved experimentally to describe the normalized heat load for real-world fires with fair accuracy. The normalized heat load concept offers a simple means for converting fire severities into fire resistance requirements, and makes it possible to design buildings for prescribed levels of structural fire safety. The potential of fires to spread by convection and the expected characteristics of fires of noncharring plastics are also discussed. Reference: T. Z. Harmathy, Postflashover Fires—An Overview of the Research at the National Research Council of Canada (NRCC), 1970–1985,Fire Technology, Vol. 22, No. 3, August 1986, p. 210.     

Protecting fire fighters exposed in room fires,part 2: Performance of turnout coat materials under actual fire conditions

Seven experimental fires varying in fire load were conducted in a simulated townhouse. Specimens of various current fire fighters turnout coat materials were exposed in the room of fire origin. The time at which conditions would become untenable for the fire fighter due to pain, as well as the time to second degree burn, were calculated. These times ranked the coat specimens in roughly the same order as the Thermal Protection Performance measured according to NFPA 1971–1986, especially if the heat in the room developed rapidly.This paper is a contribution of the National Institute of Standards and Technology (formerly National Bureau of Standards) and is not subject to copyright.     

How alcohol-related crashes of different severity interrelate and respond to local spatial characteristics:An evaluation of a common site sales ban on alcohol and gasoline

Highway safety is an important issue in both urban and rural areas. Based upon a unique panel of incorporated cities over a 96-month period from January 1982 to December 1989, this paper evaluates the effects of the State of Californias ban on common site sales of gasoline and alcohol to curb drunk driving. Geographic information systems (GIS) contribute spatial variables to an analysis of the impact of the ban on several categories of alcohol related crashes: fatalities, serious injuries, and property damage. By considering the types of alcohol-related crashes for the five-county Los Angeles area as interrelated, a seemingly unrelated regression (SUR) model locates more precise impacts. Overall the ban appears to reduce fatalities, serious injuries, and property damage crashes; but in relatively less population dense cities, the ban increases property damage and may increase more serious crashes in some urban neighborhoods. This suggests that the ban discourages highly impaired drivers but may motivate less impaired drivers to travel to an alternate alcohol purchase site. Diverse experiences in adjacent municipalities warn large regional or nation-wide evaluations of highway safety to take care when adopting large region or state fixed effect adjusters in analyses that presume sub-region homogeneity.Received: October 2003/Accepted: February 2004All correspondence to: Clifford A. Lipscomb. The authors would like to express their appreciation to Subrahmanyam Muthukumar for his assistance in preparing the GIS spatial variables. The views expressed in this paper are solely the authors and do not necessarily reflect the views of either the Bureau of Economic Analysis or the U.S. Department of Commerce.     

Smoke Control in Hospitals

Full scale fire tests have been carried out in order to study the influence of different ventilating principles on the time point of fire detection and the smoke filling of a four-bed room. Using conventional mechanical ventilating systems as smoke exhaust systems the time difference left for evacuation of the fire room can be positively influenced. With the conventional ventilating system operating there is a significant difference between time points of detection of the ionization and optical smoke detectors, for both flaming and smoldering fire. Using the low momentum displacement ventilation this difference is reduced, resulting in possibilities for the ionization smoke detector to be optimized for both flaming and smoldering fires. Reference: Øystein Meland and Eimund Skåret, Smoke Control in Hospitals,Fire Technology, Vol. 22, No. 1, February 1986, p. 33.     

Thermal radiative protection of fire fighters' protective clothing

A method for measuring the thermal radiative protection of actual fire fighters' garments to an incident radiative heat flux of 8.4 kW/m² is described. Typical results obtained with several conventional and prototype garments are presented. These results indicate the time to pain, and second degree burn as well as the pain alarm time. The thermal inertia of the garments is also measured based upon burn exposure time. Differences in physical properties such as garment thickness, total weight and number of layers are examined in order to establish the existence of any correlations.Issued as NRCC 26171. Reference: M. Day and P. Z. Sturgeon, Thermal Radiative Protection of Fire Fighters' Protective Clothing,Fire Technology, Vol. 23, No. 1, February 1987, p. 49.     

Full Scale Burn Tests of Television Sets and Electronic Appliances

Ten full-scale burn tests of television sets and electronic appliances were performed to: (1) demonstrate the ignition propensity and fire performance characteristics of materials used in the construction of television sets marketed in the United States and to compare these to the fire performance of television sets marketed in Europe; (2) document the damage to television sets when exposed to nearby burning materials; (3) evaluate and compare the damage to television sets when subjected to different size, duration and types of fires; (4) evaluate fire damage to television sets and electronic appliances when exposed to post flashover conditions; and (5) evaluate electrical damage caused to components of electronic appliances while they are powered and subjected to exposure fires.Ignitability tests showed that television sets constructed with cabinets made of V-0 rated plastics (for the U.S. market) will not ignite and propagate a flame under the test conditions. Television sets made of HB rated plastics (for the European market) will ignite and propagate a flame under the same test conditions and the television set will be consumed in the ensuing fire. The UL 94 tests do not provide rate of heat release data; however, calorimetry test data showed that the rate of heat release and the burning of the electronic appliances and television sets were in part dependent on the size of the exposure fire.Examination of the television sets and electronic appliances after the burn tests showed that the severity of damage and type of damage varied significantly. Electrical fault activity was noted to have occurred both exterior and interior to the powered television sets as well as other powered electronic appliances. In all cases, the fire source was external to the appliance.Post fire examination after the flashover fires showed that fire pattern analysis and burn damage are not necessarily indicative of the area of origin or cause and can be misleading to even experienced fire investigators.     

The Development of a Fire Safety Evaluation Procedure for the Property Protection of Parish Churches

Incidences of fires in churches are currently exceeding those in all other historic building types. This trend is destroying irreplaceable national treasures as England and Wales contains one of the greatest collections, in terms of number and antiquity, of ancient parish churches in the world. This paper describes the development of a decision making tool to aid the custodians of parish churches in evaluating the existing fire safety provision and in gauging the cost of upgrading fire safety for property protection exclusively. The principles behind the evaluation procedure are detailed and the mechanics of assessment demonstrated. The tool, referred to as Fire(SEPC) [Fire Safety Evaluation Procedure for the Property Protection of Parish Churches] is unique in its evaluation configuration in that an acceptable level of fire safety is dependent on the vulnerability of the fabric and contents of individual churches.     

Development of Regulations in the 1990 National Fire Code of Canada on storage of Dangerous Goods

The 1990 edition of the National Fire Code (NFC) of Canada contains new requirements to regulate storage of dangerous goods in buildings. In Canada, dangerous goods are defined by the Transportation of Dangerous Goods Regulations as explosives, compressed gases, flammable liquids, flammable solids, oxidizing substances, poisonous and infectious substances, radioactive materials, corrosive substances, and miscellaneous environmentally dangerous substances. The new Fire Code regulations will apply to storage and handling of these products when they are kept in buildings, where they are no longer under the control of transportation legislation.This paper describes the process by which the Canadian National Fire Code was recently revised to address problems created when fires occur in buildings storing dangerous goods. Problems include the increased hazard to the surrounding community because of toxic smoke, runoff of contaminated fire-fighting water, and delays to normal fire-fighting operations. Key ideas that evolved as part of committee deliberations, such as the rationale for regulating products that were not previously considered to be a fire hazard, are described.     

Investigating the unexposed surface temperature criteria of standard ASTM E119

Information and data were obtained to evaluate the unexposed surface temperature criteria of standard ASTM E119. The investigation consisted of: (1) reviewing literature to obtain information on the development of ASTM E119 and the unexposed surface temperature rise criteria, (2) conducting fire tests to obtain temperature data on slabs with various materials placed on the unexposed surface and (3) conducting ignition tests on these materials to obtain their approximate temperature at ignition. The information and data increased the knowledge concerning the relationship between the unexposed surface temperature rise criteria of ASTM E119 and the ignition temperature of common combustible materials.Winner of the 1985 Harry C. Bigglestone Award for Excellence in Written Communication of Fire Protection Concepts. Reference: Kenneth J. Schwartz and T. T. Lie, Investigating the Unexposed Surface Temperature Criteria of Standard ASTM E119,Fire Technology, Vol. 21, No. 3, August 1985, p. 169.     

Vertical separation of windows using spandrel walls and horizontal projections

Actual fires and full-scale tests demonstrate the hazard of the leap frog spread of fire from a window to the one above. A spandrel wall or a horizontal projection (such as a canopy or a balcony), installed above an exposing window, protects storeys above from flames issuing from the opening. The described tests show that a horizontal projection is very effective; however, for a spandrel wall to be equally effective, an impractical height of spandrel is required.     

Fire resistance tests and differentiated design procedures — The Building Code: Aims and means

Every building should be executed and arranged in such a way or by the use of such materials that, taking into consideration its purpose and location, it will give reasonable fire safety for persons staying in the building, including proper facilities for saving the occupants and for fire extinguishment to be carried out, and also to give reasonable safety against spread of fire to adjoining buildings and activities on adjoining sites. — Danish Building Code, Chapter 6.1.1 Note: The material properties of the compartments are defined in References 3 and 4. A black furnace refers to a furnace in which the incident flux is equal toT _gas ⁴.     

A first approximation method for smoke detector placement based on design fire size,critical velocity,and detector aerosol entry lag time

An analog light-scattering-type smoke detector was tested in a wind tunnel at various low velocities. The air flow in the wind tunnel contained an aerosol concentration that resulted in a high ambient optical density, simulating smoke well above threshold optical detector density. The objective of this research was to determine the lag time to alarm, t, associated with difficulty of smoke entry into a detector. A critical velocity was identified for the smoke detector, below which the lag time increased exponentially with decreasing velocity. Increased lag time results in the detector responding unacceptably late—or not at all—even when ambient obscuration is well above limits defined in UL standard tests.A preliminary method for placing smoke detectors has been developed, based on a user-defined design fire size and the detector aerosol-entry lag time. The preliminary method applies only to flaming fires producing smoke, with the detector far from a wall and mounted on smooth ceilings. The critical velocity value used in the examples in this paper applies only to the smoke detector configuration tested in this work, at the evaluated sensitivity setting, with the optical densities reached using the generated artificial smoke. Any variation in detector housing, design, operation principle, or application with different aerosols requires specific tests to determine a different critical velocity.This paper provides the basis for further development of a smoke detector placement method based on a design fire size and the proposed detector critical velocity concept. It does not presume to report a unique critical velocity for all smoke detectors, but suggests that such a value may indeed exist, but with differing values among different smoke detectors.     

Engineering geological and geophysical investigations of a slope failure at Edinburgh Castle, Scotland

Edinburgh Castle is one of Scotlands most important heritage sites. It was built on a classic crag and tail structure where the crag consists of columnar jointed basalt and the tail of sediments protected from glacial erosion by the crag.In 1997 apparent instability was observed on the southern side of the tail. A shallow slope failure was proved to have taken place within saturated, layered, cohesive to non-cohesive, loose to dense heterogeneous fill on a slope of 44°. The date of the initial failure is not known, but is likely to have taken place over a period of many years, since at least the 1950s.Remediation works were subsequently undertaken to stabilise the slope, consisting mainly of the installation of soil nails, a bi-axial geo-grid and minor filling to mitigate the effects of the ground movements and to facilitate repair of the retaining wall.     

Development and Application of the Fire Brigade Intervention Model

A performance based building code [1] was introduced in Australia in 1996. In order that fire brigades could ensure that their functional role was maintained in the building code, a method of quantifying fire brigade roles was required. In response to this issue, the Australasian Fire Authorities Council (AFAC) formed a Performance Based Fire Engineering Committee. This committee developed a model that determines the time taken by a fire brigade to undertake its activities at a fire scene.The Fire Brigade Intervention Model [2] is an event-based methodology, which quantifies fire brigade responses employed during a structure fire from time of notification through to control and extinguishment. It has been primarily developed for use in fire engineering design in a performance based regulatory environment so that the functional role of a fire brigade can be effectively incorporated into the building design process. It establishes a structured framework necessary to both determine and measure fire brigade activities on a time-line basis. It interacts with the output of other sub-systems, which model such events as fire growth, smoke spread, fire spread, detection and suppression as well as occupant avoidance.This paper describes the Fire Brigade Intervention Model, now available for use by fire brigades and fire engineers. The model has been developed for specific case and site analysis and is applicable to most structural fire scenarios. As the expertise of the local fire brigade will be incorporated inthe input parameters, it is valid for most brigade types, crew sizes and resource limitations.This paper also describes ongoing developments including a training package and computer program.The terms fire brigade and fire department are synonymous.     

Sublethal Effects of Fire Smoke

Fire smoke toxicity has been a recurring theme for fire safety professionals for over four decades. There especially continue to be difficulty and controversy in assessing and addressing the contribution of the sublethal effects of smoke in hazard and risk analyses. The Fire Protection Research Foundation (FPRF), the National Institute of Standards and Technology (NIST), and NFPA have begun a private/public fire research initiative, the International Study of the Sublethal Effects of Fire Smoke on Survival and Health (SEFS) to provide scientific information on these effects for public policy makers. The papers in this issue of Fire Technology present results from the first phase of the project: estimates of the magnitude and impact of sublethal exposures to fire smoke on the U.S. population, the best available lethal and incapacitating toxic potency values for the smoke from commercial products, the potential for various sizes of fires to produce smoke yields that could result in sublethal health effects, and state-of-the-art information on the production of the condensed components of smoke from fires and their evolutionary changes during transport from the fire.