Authors and other members have been discussing and constructing a framework of risk-based fire evacuation safety design method in a working group of JAFSE. In the framework, it is necessary to determine a benchmark fire risk level to select design fire scenario and some other evaluation parameters appropriately. In this paper, authors are trying to develop the benchmark fire risk level by using 10-year statistical data in residential fire. Statistical analyses show that the fire risk level is different between type of dwelling and structure. And the authors consider the points that should be aware of when we apply the risk level to another usage of buildings.
In performance-based evacuation safety design method at present, consideration of fire risk has been insufficient. In order to develop the framework of performance-based evacuation safety verification, the authors have proposed a methodology for selecting both design fire scenarios and design fires based on fire risk in fire, which we call Risk-based Evacuation Safety Design Method. In the Risk-based Evacuation Safety Design Method fire growth factor α and its distribution f(α) is one of the key points. We analyze the data of fire growth time (t) and burned area (Af) in the national fire statistics in Japan to obtain distributions of fire growth factor in real fire situations in terms of burned area. Then we estimate a heat release rate per unit floor area using the existing fire load density survey and burn experiments. The distributions of fire growth factor f(α) are obtained by multiplying the burned area growth factor (Af /t2) and the heat release rate per unit floor area (q"). It is found that the distributions of fire growth factor f(α) follows Log-normal distribution and that the fire growth factors from the existing experiments are within a reasonable range of the distributions.
This paper describes the pioneering research, which implies the possibility and extension of the molecular biology approach in fire research. Metagenomics analysis, which is the state-of-the-art technology currently used for the elucidation of the human gut flora, is applied to fire research. Metagenomics analyzes all the DNA of bacteria in refuse-derived fuel, i. e. RDF, bypassing the need to isolate and culture individual microbial species. In order to elucidate the biological characteristic of RDF, whose silo explosion occurred at Mie prefecture in 2003, bacterial communities in two kinds of RDF, Kuwana's and Sakura's, are revealed for non-culture and 3-day anaerobic culture conditions. Hydrogen producing bacteria such as Bacillus sp. and Clostridium sp. were found in both samples. In the initial non-culture condition, hydrogen-producing bacteria are 30% of the entire community and then increased to about 60% in 3-day culture condition. Bacillus sp. became predominant microbial in Kuwana's RDF and Clostridium sp. in Sakura's RDF, respectively after 3-day culture condition.