This study examined the growth characteristics and carbonization pattern when a fire occurs due to a flammable liquid sprinkled on a vinyl floor. When acetone was sprinkled on a floor, the flame reached its peak in approximately 0.2 s after it was ignited. The lower part of the flame showed a laminar pattern while the upper part showed a turbulent pattern. The pattern showed a turbulent pattern and generated white smoke. The combustion completed floor surface showed carbonization of a dim pore pattern. In the case of benzene, an intense flame was formed in approximately 0.6 s after ignition. The flame length was measured to be approximately 50 mm. When the flame became weak, a significant amount of black smoke was generated due to incomplete combustion. The combustion completed floor surface showed carbonization of a pour pattern and splash pattern. In the case of alcohol, an intense flame was formed in approximately 1.1 s after ignition. In addition, the depth of carbonization was significant where the flammable liquid was collected and a trace of carbonization was observed at the boundary of the flow path of the flammable liquid.

This study analyzed the flame characteristics when igniting 200 ml of flammable liquids containing equal parts gasoline and another flammable liquid. These mixtures were used to fill a divided space in a simulation. The length of one side of the divided space was 2,000 mm, and the length of the combustion device was 1,000 mm. The mixture with alcohol had the highest flame propagation speed (0.7 s), while the mixture with light oil showed the lowest (1.2 s). The gasoline and acetone mixture reached peak flame in 25.5 s, at the highest speed, while the mixture with light oil reached peak flame in 163.7 s at the lowest speed. The gasoline and light oil showed the longest continuous combustion time (332.7 s), while the gasoline and paint thinner showed the shortest (121.5 s). A fire inspector who is examining the scene of a fire needs to analyze both the statements of the first eyewitness and the flame characteristics collectively.

The purpose of this study is to analyze the flame propagation speed, radiation range, diffusion pattern and combustion completion time of a fire by filling a divided space with single combustible substance. It was found that the flame propagation speed was the fastest (0.2 s) for kerosene and the lowest (82.1 s) for alcohol. In the case of paint thinner, it took 19.0 s for the flame to reach its peak at the fastest speed after ignition while in the case of alcohol, it took 138.6 s for the flame to reach its peak at the lowest speed. In the case of the combustion of 200 ml of flammable liquids, the combustion completion time was 79.9 s for paint thinner, which is the shortest, 135 s for gasoline, 170 s for kerosene, 231.4 s for diesel and 337.0 s for alcohol. In addition, when flammable liquids are combusted, the lower part of the flame is governed by laminar flow pattern and the upper part of the flame showed turbulence pattern. In the case of a test performed for bean oil, it could be seen that if the fire source was removed, the flame was automatically extinguished without further combustion and that white smoke was generated due to incomplete combustion.

The purpose of this paper is to analyze the carbonization pattern and operation characteristics of an MCCB. The MCCB is consisted of the actuator lever, actuator mechanism, bimetallic strip, contacts, up and down operator, arc divider or extinguisher, metal operation pin, terminal part, etc. When the actuator lever of the MCCB is at the top or the internal metal operation pin is in contact with the front part, the MCCB is turned on or off. It means trip state if the actuator lever or the internal metal operation pin moves to back side. In the UL 94 vertical combustion test, white smoke occurred from the MCCB when an average of 17~24 seconds elapsed after the MCCB was ignited and black smoke occurred when an average of 45~50 seconds elapsed. It took 5~6 minutes for the MCCB surface to be half burnt and took an average of 8~9 minutes for the MCCB surface to be entirely burnt. In the UL 94 test, the MCCB trip device operated when an average 7~8 minutes elapsed. If the MCCB trip has occurred, it may have been caused by an electrical problem such as a short-circuit, overcurrent, etc., as well as fire heat. From the entire part combustion test according to KS C 3004, it was found that the metal operation pin could be moved to the MCCB trip position without any electrical problems.

The purpose of this study is to analyze combustion patterns by filling a specific container with a flammable liquid and performing combustion tests in a divided space. The container used for the test is made of plastic, 20 mm in depth and 150 mm in width. After the liquid was ignited, its combustion process was photographed using a digital camera and video camera. It was found that in the case of benzene, the flame reached its peak at the fastest speed about 60 s while in the case of alcohol, the flame reached its peak at the lowest speed about 360 s, which is approximately six times slower than the benzene. In most cases, when the flame reached its peak, smoke generated was dark as the plastic container and flammable liquid were combusted simultaneously. After completion of the combustion, it was possible to sample oil vapor from all flammable liquids excluding soybean oil as a result of the examination of oil vapor using a crime investigation tube. That is, it can be seen that there is significant difference in flame propagation speed, pattern, etc., depending on the combustible substances.