We have investigated behavior in a poorly ventilated compartment using a methyl alchol pool of 30cmφ as a source in a box of 2m(W) ×3m(L) ×0.6m(H). Temperatures, gas concentrations of CO, CO₂, O₂, and methyl alcohol vapor, fuel consumption rate, and air exchange rate were measured simultaneously. The level of the fuel surface was kept constant during the tests by means of automatic fuel supply system. The flame began to detach from the fuel surface as the oxygen concentration decreased to about 6 vol. %, it color then bocoming pale blue. The flame later detached from the fuel surface and a "ghosting flame" was observed for 20-40min. In the poorly ventilated burning conditions, it was revealed that the air exchange rate was about 5 litters/sec, oxygen concentration was about 13-14 vol. %, and the burning rate was about 0.3-0.33 g/sec which was almost 1/5 of the normal burning rate. Based on the O₂, and CO₂ concentrations and air exchange rate, the fuel comsumption rate was estimated and which corresponded to the consumption rate measured. It was found that three times of the stoichiometrically required ventilation was occurred in the ghosting period and it ensured complete combustion of methyl alcohol.

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This paper illustrates the use on an infrared image processor as a new temperature measurement and display method of the heat flow formed by an extended flame from an opening using a reduced model. In order to visualize the temperature distribution of the hot air, a stainless steel net and a ceramic sheet were set in the path or the heat flow as subject for the infrared image processor during separate experiments. The visualized temperatures were compared with the corresponding temperatures obtained by using chromelalumel thermocouples. Temperatures obtained by the infrared image processor were lower than the ones indicated by the thermocouples. The upper part of the thermal trajectory line (i.e. maximum temperature line along the flow) obtained by the visualized temperatures was located further from the vertical wall than the ones indicated by the thermocouples and Yokoi's data. This newly developed method gave a clear and wide enough temperature contour map for the experimental study of the flame extention.

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The purpose of this study is to propose a method to estimate the quantitative life risk of patients in case of hospital fires. In this method, life risk is defined for each room of the hospital as the expected times per unit time for a patient to be trapped by smoke. This method has been applied to some existing hospitals, and the results have proven to be useful in judging safety design of a hospital.

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Theoretical and experimental numerical analysis shows the capabilities of finite difference calculations of fine induced natural convective heat flow in a compartment. The viscous, heat conductive, compressible fluid is represented using a K-ε model. Because a two-point upwind difference scheme gives numerical viscosity, the computational results are suspect at large velocities. The practical stability limits and truncation errors for finite difference equations approximating flows have been analyzed. The sensitivities of numerical solutions have been evaluated by the theoretical and experimental numerical analysis. Based on results of numerical experiments we propose a reasonable time interval and space mesh size criteria which also considers CPU time. Furthermore, we have introduced the effective maximum cell Reynolds number (Re∗) for the equation of motion, or the effective maximum cell Peclet number (Pe∗) for the equation of energy. We propose that the values of Re∗ and Pe∗ indicate the trust which may be placed on the approximate solutions.

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The characterization of the smoke generation and reduction was pursued on the basis of the size distribution of smoke particles from wood and several retarded wood materials. Furnace temperatures were adopted of 300, 400, and 500°C due to the peak temperatures which were obtained from thermogaravimetry. The sizing instrument for smoke particles used a He-Ne laser as the light source, and the particle size range extended from 0.1 to 10 μm in by nine steps. For low smoldering state, the combination of molybdenum, bromine, and phosphate compounds as retardant agents gave the most desirable reduction of smoke particle generation in the experiments. And for higher temperature region, the combination of molybdenum and bromine compounds gave remarkable reduction of smoke generation.

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Four full-scale tests were conducted in a compartment designed to simulate two adjacent residential spaces protected by quick-response sidewall sprinklers connected to a limited water supply. A living room furniture arrangement, consisting of a recliner, drapes, table, sofa end and carpet, was placed in one space and served as the source. Although two sprinkler placement achemes and a lintel in the opening between the spaces were tried, sprinklers installed in both spaces of the compartment actuated during each of the four tests conducted in this study. In all tests, sidewall sprinklers (a) controlled the and prevented flashover of the compartment, (b) confined the to the recliner (primary ignition item), and (c) allowed a survivable life safety environment to be maintained throughout the test period, thereby meeting the designed purpose of a residential sprinkler system. However, the inherent delay in response time associated with the use of sidewall sprinklers resulted in high ceiling surface temperature over the source location which indicated a property damage potential for combustible ceilings.

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Six sprinklered office tests were performed to determine the feasibility of using quick-response sprinklers to protect office occupancies. Tests were conducted in a furnished 4.6 m × 9.1 m × 2.4 m high compartment with a horizontal smooth ceiling designed to simulate an executive-type office suite. The suppression effectiveness of quick-response, slow-response, and concealed sprinklers was examined. Conditions for the six tests were selected to provide evaluation of the effects of sprinkler response, one compartment ventilation condition and sprinkler water discharge rate upon overall sprinkler performance. In all six tests, sprinklers controlled fires and prevented flashover of the compartment regardless of initial test conditions. However, different levels of protection were provided when sprinkler link sensitivity, water discharge rate and the ventilation condition were altered. The slow-response sprinkler and the concealed sprinkler tested did not respond quickly enough to achieve the same level of life safety or property protection afforded by the quick-response sprinkler used in this series of tests. Test results also indicate that a reduction in sprinkler water discharge rate for quick-response sprinklers and changes in ventilation significantly affected sprinkler system effectiveness.

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Heat flux out of a burning wooden house was studied. In a full scale experiment of a three story wooden house, which was recently executed in Tokyo, Temperature of heat source was examined using a thermal camera. Data was converted to heat emission rate and for the validation of the conversion method, the data was compared to radiation data measured by conventional flux gauges. In another experiment and heat emission from different portions of building facade was studied. This paper is a revised version of ref. ^[1]

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A field equation model was developed for the interaction analysis of turbulent natural convection and radiation in the 'pre-flashover' compartment . Radiation in non-gray gases and soot mixtures was analyzed by a differential approximation method. A κ - ε model for turbulent flow was considered. The Favre (mass) averaged governing equation system was solved by an efficient iterative method incorporating a multi-dimensional simultaneous finite difference equations solver. Computations were performed on a two-dimensional room-corridor system with a localized source in the room. Effects of radiation on the flow and temperature fields have been identified. Soot radiation significantly altered local characteristics of the temperature field.

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A past investigation of the flow of hot gases in roof venting led to the development of a simple zone model which for many years has formed the basis for the design of practical roof venting systems. Although calculations of equilibrium depths of the layer of hot gases agree with the results of large-scale experiments, there were no large-scale experiments against which calculations of increase in depth with time could be validated. Recent experiments of Yamana and Tanaka have provided such data and in this paper their results are compared with the predictions of the original model. Calculations have also been made for situations where Yamana and Tanaka did not calculate the increase in depth with time. The correlation is at least as good as that provided by the more recent model of Tanaka and Yamana. There is some evidence that when the layer of hot gases had fallen to within 3 m of the floor of the unvented compartment smoke-logging followed rapidly. This is not predicted by simple models.

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Software-controlled detecting installations are of increasingly gowing importance and attraction. The paper discusses the advantages as the main reasons for this fact. In addition it gives an indication of the problems to be solved and the inherent failure sourcses. The main applicable design rules are derived from the principle that failure sources have to be avoided and where they are unavoidable their effects have to be minimized. The basic design approaches are discussed in this context. It is mentioned that in practice a combination of several aspects has to be applied for several reasons. Testing is necessary on the different levels of the design, development and application process. The contribution discusses the possible test philosophies for type testing in some detail and mentions a special test procedure for software-controlled detection systems which has been discussed in the European community and which is a compromize between a rigorous functional (dynamic) testing and a documentation check. It is likely to give suitable over-all indication of the system quality, it checks several key specifications and it keeps the testing expenses at an acceptable level.
It is shown that black-box testing is not possible.

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The design method of building structures has been trending from allowable stress design method to ultimate state design method. The ultimate state design method is based on the assumption that load bearing and deformation capacity of plastic hinges are ensured sufficiently. Using the ultimate state design method in engineering desing, it is necessary to investigate load bearing and deformation capacity at elevated temperature. In this study, the load bearing and deformation capacity of H shaped steel members are obtained experimentally under three stress conditions at elevated temperature.

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Methodologies on systems approach might be useful for the synthetic estimation of building safety. However, the meaning of their formula often seems obscure or irrational. This paper has a discussion on the characteristics of systems-structures applied to each method. For example, Gretener's method is basically composed by a divisional formula, which belongs to an emphatic expression with the ratio of hazard potential to safety countermeasures. The other discussions are on the point-making methods determining an effectiveness of facilities, with a tentative result of double effectiveness of sprinkler systems to heat detector equipments.

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General geometry and height of diffusion flames and the height-dependence of centerline temperature above propane burners of relatively low heat release rate for the fuel size are described. The flame behavior is classified into 3 regimes according to the difference in the height-dependence of centerline temperature and in the general behavior of the flame. Flame height is represented as a function of Q∗ = Q/ρ₀C_pT₀g^1/2D^5/2. The criterion for the adequacy of the concept of "virtual source" for the prediction of centerline temperature from the point-source turbulent plume theory is discussed.

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The heat generation values for the typical smoldering sources which have been proposed as the ISO Standard on Detector Test were estimated experimentally based on oxygen consumption and weight loss rates. Heat generation values of smoldering wood and cotton wick showed 1/10 - 1/3 of those of flaming phase. The heat generation rate which was proposed as the Standard of ISO Source was 1.5 kW and gave excess temperature of 2 - 2.5°C under the ceiling of the proposed ISO test room. It was found experimentally using the test room and proposed smoldering sources that the hot layer under the ceiling of which excess temperature of 2 - 3°C stopped the penetration of updraft smoke from the smoldering source through the thermal interface. It should be necessary that the exact definition on vertical thermal condition for the proposed ISO Test method to get repeatability, reliability, and sensitivity of the detector tests.

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A mathematical model for estimating structural performance of reinforced concrete beams exposed to has been set up by combining two mathematical submodels for calculation of temperature and structural performance. And the validity of the model has been verified by experiments on two dimensions of full scale beams. For listing the damage of 720 types of beams with different specifications such as dimensions, total amount and compressive/tensile cross-sectional area ratio of reinforcing steel bars to be included in the beams, the mathematical model has been applied. Some of the results are presented as examples in this paper.

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The pseudo stationary state of silicone oil has been defined from the analysis of the pyrolysis of silicone oil in nitrogen by means of the high radiative heat flux furnance method. The model of this state has been established by considering it as the vaporizing process of the pyrolysis products of silicone oil. From the modeling, the pyrolysis difference between the low radiative heat flux and high radiative heat flux have been observed and these mechanism have been clarified by the IR spectra and the viscosity-average molecular weight.

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A simple one zone and transient model of compartment fires was proposed to predict behaviors and flashover. The calculated results obtained from this model were compared with the experimental results, and further with the HARVARD CODE V with some discussion. The model presented here could make prediction of flashover time, though it's quite simple. Provided some properties of wall and burning materials, room size and opening conditions are input, behavior and flashover time are obtained. Calculated results were in good agreement with the experimental results obtained from the reduced scale model compartment. Based on these results, flashover time became minimum at a certain value of A√H. Similar results were obtained from calculation of HARVARD V for the full scale situation.

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