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Considering the age and longer service time of firefighters who have a substantial amount of field activities, they are exposed to chemical and biological risk factors, physical and mental stress, diverse and complex work environments, and repetitive motions, which may increase the rates of gastrointestinal disorders, musculoskeletal diseases, cancers, and cardiovascular diseases. Therefore, based on the regular specific health examination results for 215 firefighters who were working in the N fire department located in B metropolitan city, an analysis of occupational diseases was performed, which showed that the most common chronic disease was diabetes mellitus (28.8%), followed by hyperlipidemia (27.9%) and thoracic diseases (19.5%). This trend appears to be consistent with the incidence rates reported in a representative study of adult diseases in Korea. In addition, it was found that 82 officers maintained healthy states, while those who needed further medical inspection and those with clinical symptoms were more frequently exposed to disease when they were older and had longer service time; moreover, the fire captain and lieutenant had higher rates of disease.

With the recent enlargement and complication of buildings, damage caused by the incidents of fires breaking out are escalating. Consequently, the use of sprinkler facilities is increasing among water-based fire extinguishing systems. Piping materials used in fire prevention systems include carbon steel (for general or pressure pipeline), CPVC, copper, and stainless-steel. Among these, the steel and CPVC pipes, which are commonly employed in fire prevention, were considered for testing the reliability of the water-based systems. This analysis was performed using the PIPENET software to perform hydraulic calculations in order to examine the flow and pressure at the terminal head when the corrosion coefficient was applied; this coefficient was applied considering the aging of pipes. Assuming a uniform pipe diameter in the steel pipes, the rated flow in the pump installed on the first floor of the basement was reduced by over 10% after 20 years had passed (C value of 90); moreover, the reduction in pressure and flow at its terminal head exceeded 30% and 16.5%, respectively. The results indicate that it is difficult to ensure the reliability of these fire prevention facilities. Furthermore, according to our estimation, considering 30 years had passed (C value of 80), the rated flow of the pump was reduced by over 15%, and the corresponding reduction in pressure and flow at its terminal head exceeded 42% and 24%, respectively.

This study aims to maintain the safety of an outdoor storage tank through the fundamental case analysis of explosion and fire accidents in the storage tank. We consider an accident caused by the explosion of fire inside the tank, as a result of the gradual spreading of the residual fire generated by wind lamps flying off a workplace in the storage tank yard. To determine the cause of the accident, atmospheric diffusion conditions were derived through CCTV image analysis, and the wind direction was analyzed using computational fluid dynamics. Additionally, the amount of oil vapor inside the tank when the floating roof was at the lowest position, and the behavior of the vapor inside the tank when the floating roof was at the highest position were investigated. If the cause of the explosion in the storage tank is identified and the level of the storage tank is maintained below the internal floating roof, dangerous liquid fills the storage tank, and the vapor in the space may stagnate on the internal floating roof. We intend to improve the operation procedure such that the level of the storage tank is not under the Pontoon support, as well as provide measures to prevent flames from entering the storage tank by installing a flame arrester in the open vent of the tank.

Autoignition characteristic is an important factor of all combustible substances, and a critical determinant in assessing the effectiveness of fire hazard prevention. This study investigated the autoignition characteristic of mixtures of Ethylene Glycol and water using an ASTM D2155 type ignition temperature measuring apparatus. It was possible to get the minimum temperature as 434 C from 100% Ethylene Glycol within range of 75~160 µl. A volume of 100~125 µl of a mixed sample of Ethylene Glycol and water (80 : 20) was ignited at the same temperature (434 C). Also it was possible to get the auto ignition temperature as 437 C from a mixed sample of Ethylene Glycol and water (60 : 40) within range of 120~ 160 µl. The instantaneous ignition temperatures determined for 125 µl of each of the three samples were 579 C, 595 C and 611 C, respectively. Both auto ignition temperatures and instantaneous ignition temperatures were increased through the addition of water to the samples.

In order to examine the explosion risk of 2-ethylhexanoic acid, we experimentally studied the explosion limit, explosion pressure, and rate of increase of the explosion pressure at different oxygen concentrations. The lower explosion limit was 3.2% at a temperature of 100 C, and the oxygen concentration was 40 to 70%. The upper explosion limit was 4.5% and the lower explosion limit was 4.0% at an oxygen concentration of 21%.The maximum explosion pressure of 2-ethylhexanoic acid was 1.4161 MPa at an oxygen concentration of 70%, and the rate of increase of the explosion pressure was 62.692 MPa/s at this concentration.