The fire-signal sharing system installed nearly a generation ago in Takayama-sanmachi historic district is revisited to verify its effectiveness in mitigating fire hazard, causes for non-fire actuation of detectors and its acceptance and perception by the local residents. Impact of the change of the generation, residents and lifestyle in the district on the regional fire safety is also investigated. The study suggests general effectiveness of the system, yet ageing and change of residents have resulted in the reduction of the intimacy within the community, the essential basis for the effectiveness of the system.

In this study, the structure of flame of magnesium was experimentally examined by using ion probes and a Schlieren system. Using an ion probe with a long sensing part, the current of the entire flame of magnesium and filter paper were measured. It was found that the current of flame of magnesium was 10⁴ times larger than the current of flame of filter paper. Areas of inner and outer flame and oxidation were observed by a Schlieren system. Using a pair of ion probes with a short sensing part, to compare the ion generation in the bright inner flame and in the outer flame, where oxidation is take place. A small current was measured in the outer flame, and an extremely large current was measured in the inner flame. The current of the outer flame was extremely large compared to the flame of the filter paper.

An experimental study was conducted to statistically compare the ignition potential of Reduced Ignition Propensity (RIP) cigarettes with that of conventional cigarettes using Japanese style bedding, futon, in order to examine the effectiveness of RIP cigarettes in the context of Japanese fire scenarios. Number of ignitions of futon caused by two different types of cigarettes, namely, conventional cigarettes (Non-RIP) and RIP cigarettes were examined in a variety of testing conditions on compressibility of futon, wind velocity, temperature and humidity. Difference in the number of ignitions of futon observed in different test settings were statistically compared by Fisher's exact test to examine whether experimental parameters such as the cigarette types, materials of futon, and a variety of conditions contribute to the ignition. Additionally, logistic analysis was conducted to examine how the experimental parameters contribute to the ignition. Test results showed no significant difference between Non-RIP and RIP (as a result of Fisher's exact test; P < 0.05) in either test configuration. Filling materials of futon, compression ratio of futon, humidity and wind velocity are thought to be greater contributing factors to the ignition at least under the experimental conditions examined in this study.