Earticle

In Korea, all three sides are surrounded by the sea, so trade and fisheries using ships have been developed. However, regardless of safety, domestic ship fires occur frequently every year. Among them, fires on large cargo ships or ferries have been a social issue, but the actual number of ships registered with the Ministry of Oceans and Fisheries is only about 12%. Of the remaining 88 percent, 83 percent are small fishing boats, and many fires are also occurring in these boats. Among them, not only fishing boats under sail but also fishing boats under moorings cause fire due to short circuits and battery-related causes, causing great property damage, such as combustion expansion nearby. Therefore, this research focuses on the battery, which is one of the causes of fire in fishing boats, and analyzes the possibility of firing of the battery through fire investigation and Reproduction experiment and suggests ways to reduce damage, such as minimizing fire and preventing combustion.

In this study, NCM cathode materials were mainly analyzed to confirm the fire risk of LIB. NCM cathode materials have poor surface stability and poor structural stability at high temperatures, so gas is generated and the cell swells, causing swelling. To confirm this phenomenon, a pouch full cell was manufactured and electrochemical output characteristics were tested, and it was confirmed that the cell surface temperature risen to 60°C. As a result of ICP-MS analysis, it was confirmed that the higher the ratio of Ni in the NCM cathode and the higher the temperature environment, the higher the solubility of Ni. In fact, the pouch full cell was stored in a high-temperature oven for a total of 4 weeks, and the swelling behavior was measured at intervals of 1 week, and the amount of gas generation was quantitatively measured through the internal pressure cell. As a result, the higher the Ni ratio, the more gas generated. In order to determine the correlation between these gas emissions and fire, harsh conditions were applied via a DC power supply. As a result, it was confirmed that the higher the ratio of Ni and the greater the number of charging and discharging, the more the cell swelled, the faster it exploded, and the higher the temperature at the time of explosion.

On February, 21, 2021, In Imdong-myeon, Andong-si, Gyeongsangbuk-do, a forest fire broke out. The carelessness of the grave visitor was considered to be the cause of the forest fire. It was able to estimate what and who started the fire through the following: the statement of the person who reports the fire, combustion pattern in the scene, the debris of the incense and candle found at the scene, and others. However, It was hard to clearly determine what and who started the fire only with the above-mentioned clues because of insufficient scientific evidence. In this study, thus, a direction of forest fire investigation was presented by comparing and analyzing the possibility of fire caused by incense and candle, and the resulting combustion pattern. Also, risk that grave visitors can easily cause has been studied in this paper.

In modern society, many materials have been developed for various purposes such as building enlargement, convenience of architecture, and economy. The types of EPS and PUR used in large logistics warehouses are very vulnerable to fire, and it is difficult to know in advance the progress of combustion and the risk of rapid combustion expansion due to external materials. This paper confirmed the generation of flammable vapor due to external sequence of panel types installed in a sealed state, and analyzed the components of mixed gas using gas chromatography. In the mixed gas, gas components such as carbon monoxide, methane, and the like were identified, and it was found that the gas was mixed with oxygen in the air when the external material was deformed by external heat and rapid combustion was expanded. This is to measure the components of smoke generated during fire suppression in large logistics warehouses to identify the combustion status of internal cores and suggest the need to provide information to the safety management of field personnel.

The Airfryer is a tool developed to make frying food at home easier while saving cooking oil. Literally, it is an electric appliance that cooks food with radiant heat and hot air generated by a high-temperature heating element. When using the air fryer, the manufacturer recommends lightly oiling the food before cooking in the instruction manual to create a crispy texture unique to frying. Separately, to make the air fryer easier to clean after cooking, regular users often operate the air fryer by putting paper foil on the inside of the frying pan and putting ingredients greased with cooking oil. However, a fire presumed to be caused by this method of use occurred. It was estimated that the cause of the fire was that the hot air inside the product should be smoothly discharged to the outside by forced convection by the rotating fan inside the air fryer, but it was obstructed by the paper foil. As a combustible material, it was judged that the possibility of ignition was sufficient when the cooking oil was changed to a high-concentration oil vapor by the heat of the heating element inside the device and came into contact with the high-temperature heating element. Therefore, in the reproduction experiment, when paper foil was not used, the temperature inside the device only rose to 219°C, the smoke point temperature of general cooking oil, but reached 314°C when paper foil was laid. This is close to the ignition point of general cooking oil of 330°C.

Fires in the fire switchboard are constantly occurring and efforts are being made to improve them. Most of the causes of fire in switchboards are due to poor contact at terminals, dust and water inflow. Among them, we have checked the possibility of fire caused by water inflow through fire cases, installation status, and combustion experiments. We have also confirmed that there are no specific criteria regarding electrical equipment, although the technical standards of the Ministry of Trade stipulate that “the structure would not allow water to permeate into the distribution box.” Therefore, this study warns of fire hazard caused by water inflow switchboard through the results of fire reproducibility experiment, and it expects that the supplementation of laws to improve the environmental factors that bring moisture into switchboard. We hope that the fire investigation will develop from the center of ignition source and factor to the center of fire prevention measures and contribute to fire prevention.

It is intended to confirm the fire risk of cigarette fires by analyzing the fire statistics of cigarette fires, which are the main causes of fire, and setting the firing conditions for each condition. The purpose is to establish firing conditions based on recent cigarette fire statistics to prove the possibility of fire, and to secure reliability by scientific consideration and experience accumulation of representative cigarette fire in microfurnace. In addition, it is intended to derive objective results from joint re-realization experience with related agencies.