The electrical molten marks (EMMs) are often found in the place where the fire started in. Therefore, when the fire causes are investigated, EMMs have the possibility that they become the big clue which makes the cause clear.
The following two cases were experimentally studied as a fundamental research which is necessary to establish the method of distinguishing the Primary Molten Marks (PMMs) from the Secondary Molten Marks (SMMs) ; (1)In order to research whether thermal histories affects the grain size of non-melted wire which is adjacent to EMMs or not, the grain size of copper wire exposed to various heating and cooling conditions is examined. (2)In addition, it was also researched that there were some differences of properties in external features, cavities and metallographic structures of the PMMs and SMMs made under the several different conditions.
As a result, following were obtained.
1) The grain size of the copper wire has no relationship with the cooling conditions and spontaneous heat of wires prior to the heating, but depends on the highest heating temperature only. Therefore, it is ineffective to use the grain size to distinguish PMM from SMM.
2) It is unreasonable to discriminate between the PMMs and SMMs by the external features and cavity distribution of the EMMs.
3) When the surface of the copper wire was oxidized after the exposition to the air, the oxidation structures, which reflect the effect of the oxidation before the production of EMMs, are observed from the EMMs. And oxidation structure is formed not only by oxidation of surface before short-circuit, but by oxidation during coagulation after short-circuit through absorption of ambient oxygen.
4) It is considered that the oxygen of the air is absorbed at the melting and coagulating process and then the oxidation structures could be found even when the oxygen concentration is low as in case of fire, since the oxidation structure was admitted by the ambient of oxygen concentration 2. 5%.

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The purpose of this paper is to propose a simple calculation method for the determination of air supply rates in pressurization smoke control system in fully developed stage of fire. The air supply rates are calculated under isothermal condition except for the considerations of the condition to prevent smoke flow through the opening and the stack effect between the vertical space and the outside. Further the effect of the outdoor wind and the prediction of the corridor temperature in fire floor are considered by a simple method in this paper.
The validity of the proposed simple method is examined by making comparison with more precise computational one zone model.
As a result the proposed simple method is in good agreement with the computational method in case study of a building. It is shown that the considerations of the stack effect, the air leakage through non-fire floors, the outdoor wind and the appropriate condition of temperature are important to predict the appropriate air supply rates by the simple method.

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To examine the mechanism of high-speed flame spreading phenomena across napped fabrics (surface flash), temperature profile was measured on a surface flash flame spreading downward by using fine wire thermocouples. The measured temperature profile was compared with that of normal flame spread. It was found that temperature gradient near a surface flash flame is much milder compared with that of normal flame spread, whereas temperature at a fixed position increases more quickly in the case of surface flash. Also the distance between the leading edge of flame and surface of fabric becomes larger in the case of surface flash. These results infer that the flame spreading mechanism of surface flash is different from that of normal flame spread, in which the flame spread strongly depends on the heat transfer into solid surface.

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The purpose of this experimental study was to depress the smoke in the fire room and the leaked smoke from the fire room by the use of spraying water-mist from the top of the smoke. To confirm the condition for sufficient water-mist spray, the diameter of water-mists and the distribution for the amount of sprayed water were measured preliminarily under the various conditions of the type of water-mist head and the spraying pressures after the selection of suitable water-mist nozzles. After the pretest, the performance for the smoke depression of the water-mist system was examined by the experiments of the spraying from the top to the smoke generated from the combustion of the lamp oil or the smoldering fire of the wood-chip and condensed into a certain enclosure space.

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The objective of this study is to evaluate available water resources for fire-fighting during the initial stage of an earthquake disaster. As a tool of evaluation, the Fire Information Management System (FIMaS) was utilized. FIMaS is a computer-based management system for fire-fighting through fire spreading simulation.
The calculation technique of required fire-extinguishing water resources in each 250 m grid in the case study area was developed for the research. Sufficiency rate was defined as an index for the evaluation of an object areas. The index is involved with "required water" / "existing water resource". Fire-fighting simulation was performed at the areas under a classification according to the rate of sufficiency. Based on the result of the study, fires were able to be extinguished in one or more grids for all the rates of sufficiency.

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