Earticle

The external factors of latex products cause a fire. Peoples are interested in a deep sleep and related latex products are widely used. But fire accidents have been increased since their preference for latex mattress got higher. Fire risk of latex products is analysed and the plan for efficient protection methods are suggested. Three kinds of latex mattresses are used and three major data is collected for the experiments. Firstly, they observe a temperature change in thermal heat build-up. Secondly, they check a flaming fire under smoldering combustion by thermal heat build-up. Lastly, they analyze heat release rate and detection density by the outbreak of toxic gases after the experiments from the above.

Improved technique to estimate heat release rate from combustion in a large-scale con-calorimeter is studied. It takes a mixing effect within a large space into account, and adds a model, based on a constant stirred tank reactor equation, that readily predicts oxygen concentration at a measuring station into the conventional HRR measurement system based on Thornton’s rule. The developed technique is then validated with a series of n-heptane pool fire tests with combustions of 68 L of n-heptane. When the combustion efficiency was assumed 100% at an open space experiment, it is 28.9 MW and natural convection is dominant for mass transport of species. As a result, HRR is 32 MW at its maximum, which is much higher than it was expected. This is caused by a vigorous forced convection near the heptane flame due to the make-up air (around 4,000 cu. m/min), which makes it be evaporated more faster.

To prevent the fire due to the overheating of coolant and the insulation deterioration, pre-heater parts are installed to improve indoor heating of winter diesel vehicles. The preheater operation method is divided into two types: a heating plug type that generates heat by electric energy and a combustion type that heats with fuel combustion heat. The experiment was focused on the heating plug method that is currently widely used. As a result of analyzing national fire statistics for the past five years, it was found that 235 (54.3%) occurred in winter (November to March) out of 432 vehicle fires in SantaFe. It is judged that this is not irrelevant to the seasonal effect of the heater rod operating under the preheater cooling water temperature of 75℃ or less, and through reproducibility experiments ➀part corrosion due to cooling water oxidation, ➁coolant overheating due to ECU defect (150℃), ➂insulation of distribution lines It was concluded that it could be ignited by deterioration. In addition, the actual vehicle fire in the preheater area was conducted to describe the combustion pattern and fire detection method of the vehicle.

With the steady increase in electricity use, electric fires account for more than 20% of the total number of fires each year. Electrical fires are caused by electrical arcs or sparks inside the cover of wires, but they are also caused by external flames melting the cover of wires into contact with each other. In electric fires, melting of wires is usually found, which is commonly referred to as short circuit. The molten marks are divided into the primary one that occurs inside the wire and causes the fire directly, the secondary one caused by external fire, and the heat melt found in the unenergized state. Scientific criteria for the distinction between primary and secondary molten mark is presented by using qualitative and quantitative analysis, through analytical chemistry such as SEM and EDS, XRD and EA.

VOCs generated from epoxy operations may be exploded by concentration above the lower explosion limit(LEL), which results in a fire hazard. The epoxy operating standards for the fire prevention and the basic data on fire identification are presented. The conditions that the VOCs exceed the LEL were evaluated as following. (1) Operating time of thinner within 5 hours, (2) Operating time of epoxy within 45 hours, (3) Ambient temperature above 12℃, (4) Not installed ventilating opening(or ventilator) or installed at 25cm or more, (5) More than 200℃ of temperature by ignition sources.

The brake fluid plays an important role in braking device. It increases the water content and lowers the boiling point and the flash point, as the travel distance is increased. The possibility of vapor lock and the risk of fire is also increased. The brake fluid leakage due to the solenoid failure in the ABS module, which is a main component of the brake system, can be ignited by the circuit board terminal trekking short circuit. It has been confirmed that the leaked brake fluid caused by overheating of the drum and the disc due to repetition of braking can be ignited even in the case of short-circuit spark and high-temperature metal contact. Also, the leakage and the injected brake fluid due to the cylinder failure of the disc and the drum brake are ignited by overheating due to braking repetition.

In the last three years, 19 life-threatening spray fires and safety accidents have occurred. The most common type of damage was burns with seven cases, followed by six electric shocks, four fires and explosions, and two others. In May 2019, there was a home fire in our port fire station where two smoke inhalers were taken to the hospital for the same type of home fire. Most consumers are aware of this explosion damage only by being aware of the cautions and following the safety rules, and by fully aware of the precautions or the fact that an explosion can be caused by the use of household spray pesticides and electric mosquito nets. It was chosen as the theme of the 2020 conference in the mind that it can be reduced.