• Title/Summary/Keyword: Gas safety

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A Study on Flammability Risk of Flammable Liquid Mixture (가연성 액체 혼합물의 인화 위험성에 관한 연구)

  • Kim, Ju Suk;Koh, Jae Sun
    • Journal of the Society of Disaster Information
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    • v.16 no.4
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    • pp.701-711
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    • 2020
  • Purpose: In this study, the risk of flammability of a liquid mixture was experimentally confirmed because the purpose of this study was to confirm the increase or decrease of the flammability risk in a mixture of two substances (combustible+combustible) and to present the risk of the mixture. Method: Flash point test method and result processing were tested based on KS M 2010-2008, a tag sealing test method used as a flash point test method for crude oil and petroleum products. The manufacturer of the equipment used in this experiment was Japan's TANAKA. The flash point was measured with a test equipment that satisfies the test standards of KS M 2010 with equipment produced by the company, and LP gas was used as the ignition source and water as the cooling water. In addition, when measuring the flash point, the temperature of the cooling water was tested using cooling water of about 2℃. Results: First of all, in the case of flammable + combustible mixtures, there was little change in flash point if the flash point difference between the two substances was not large, and if the flash point difference between the two substances was low, the flash point tended to increase as the number of substances with high flash point increased. However, in the case of toluene and methanol, the flash point of the mixture was lower than that of the material with a lower flash point. Also, in the case of a paint thinner, it was not easy to predict the flash point of the material because it was composed of a mixture, but as a result of experimental measurement, it was measured between -24℃ and 7℃. Conclusion: The results of this study are to determine the risk of mixtures through experimental studies on flammable mixtures for the purpose of securing the effectiveness of the details of the criteria for determining dangerous goods in the existing dangerous goods safety management method and securing the reliability and reproducibility of the determination of dangerous goods Criteria have been presented, and reference data on experimental criteria for flammable liquids that are regulated in firefighting sites can be provided. In addition, if this study accumulates know-how on differences in test methods, it is expected that it can be used as a basis for research on risk assessment of dangerous goods and as a basis for research on dangerous goods determination.

Analysis of Ventilation Characteristics in Ship Fuel-Preparation Rooms During Ammonia Leakage (암모니아 누출 시 선박 연료 준비실의 환기 특성 분석)

  • Jin-Woo Bae;Bo Rim Ryu;Kweon-Ha Park
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.30 no.5
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    • pp.490-498
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    • 2024
  • Ammonia is an eco-friendly marine fuel that does not emit carbon dioxide and is a primary contributor to global warming. Despite its benefits, ammonia poses significant risks owing to its toxicity, explosiveness, and corrosiveness, thus necessitating robust safety measures to manage its potential leaks on ships. This study investigates the characteristics of ammonia leaks and ventilation dynamics in a ship fuel-preparation room, with emphasis on the ef ect of varying the positions of air supply and exhaust outlets. The leakage rate is set at 0.1 kg/s, with a ventilation rate of 30 ACH (air changes per hour). The scenario with air supply at Aft - Top - Stbd and exhaust at Fwd - Top - Stbd (Case 1) results in the highest average ammonia concentration after 100 s. Conversely, the scenario with air supply at Aft - Bottom - Stbd and exhaust at Fwd - Bottom - Port (Case 14) results in the lowest concentration. After 50 s, Case 1 indicate ammonia concentrations exceeding 1500 ppm toward Aft, whereas Case 14 indicate a consistent stagnation zone along the Fwd wall. The distribution of ammonia concentration and velocity varies by height owing to the positioning of the air supply and exhaust outlets as well as the equipment configuration, thus resulting in higher concentrations in areas with slower airflow. When a small amount of ammonia leaked at 0.1 kg/s for 10 s, explosive gas formed near the leak point at a height of approximately 1 m, thus indicating an extremely low risk of explosion from slight ammonia leaks. This study confirms that the optimal combination of air supply and exhaust-duct positions can effectively control ammonia concentration. This finding is expected to contribute to the establishment of design standards and ensure safety when using ammonia as marine fuel.

Determination of Residue Levels of Ethyl Carbamate in Alcoholic Beverages by Gas Chromatography/Tandem Mass Spectrometry (GC/MS/MS) (가스크로마토그래피/질량분석기(GC/MS/MS)를 이용한 주류 중 에틸카바메이트 잔류량 조사)

  • Kim, Dong-Ho;Jang, Han-Sub;Choi, Gu-Il;Kim, Hyun-Jung;Kim, Ho-Jin;Kim, Hyo-Lin;Kim, Keun-Sung
    • Journal of Food Hygiene and Safety
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    • v.28 no.1
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    • pp.63-68
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    • 2013
  • Ethyl carbamate (EC) is a contaminant generated in the fermentation processes of various fermented foods. In this study, residue levels of EC in 95 alcoholic beverage samples were determined by using Gas Chromatography/Tandem Mass Spectrometry (GC/MS/MS). All the samples were purified by a liquid-liquid extraction (LLE) method using dichloromethane. The LLE method enables an improvement in time and cost to detection and specificity over the conventional extraction methods. The limits of detection and quantification (LOD and LOQ) to analyze EC were 1.3 and 4.0 ng/mL, respectively. The recovery rates of EC were ranged from 90.0 to 97.5% at the levels of 50, 100, and 500 ug/L. Among traditional grain-based alcoholic beverage samples (n = 34), the average residue levels of EC in takju, yakju, and cheongju were 0.63, 7.01, and 14.11 ug/L, respectively. Among fruit-based alcoholic beverage samples (n = 48), those of EC in japanese apricot spirits, bokbunjaju, grape wines, and other fruit wines were 79.18, 1.66, 2.64, and 2.39 ug/L, respectively. Among distilled or diluted alcoholic beverage samples (n = 13), those of EC in soju (distilled or diluted), general distillates, liquors, and brandies were 0, 3.30, 8.20, and 8.52 ug/L, respectively. Therefore, this study reports that the residue levels of EC in the alcoholic beverages, distributed in the current domestic markets, did not reach its maximum allowed levels of 30 and 400 ug/L established for grape and fruit wines in Canada, respectively.

Combustion Characteristics of Useful Imported Woods (국내 유용 해외 목재 수종의 연소특성 평가)

  • Seo, Hyun Jeong;Kang, Mee Ran;Park, Jung-Eun;Son, Dong Won
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.1
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    • pp.19-29
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    • 2016
  • The purpose of this study is to analyze the combustion and thermal properties in order to establish baseline data for the fire safety evaluation of imported wood. The combustion properties such as heat release rate, total heat release, gas yield, and mass loss were analyzed by the method of cone calorimeter test according to KS F ISO 5660-1 and thermogravimetric analysis (TGA). Analyzed species are five kinds of species as Merbau, Mempening, Garo Garo, Malas, and Dillenia. The heat released rate values showed the highest value of Malas as $375.52kW/m^2$, and Dillenia showed the lowest value as $133.30kW/m^2$. The data values were confirmed in the following order: Malas > Mempening > Garo Garo > Merbau > Dillenia. In case of the total heat release, it was measured in the following order: Mempening > Malas > Garo Garo > Merbau > Dillenia. The gas analysis results were that Dillenia showed the highest value of 0.034. Also, Mempening and Malas showed the lowest at 0.020 in the $CO/CO_2$. Min of mass reduction was shown as 74.79% Sargent cherry, on the other hand, Malas had a 83.52%. It showed a correlation between and of the CO and $CO_2$ generation and combustion characteristics of wood. The thermal decomposition temperature of the wood in the TGA were as follow that Merbau $348.07^{\circ}C$, Mempening $367.57^{\circ}C$, Garo Garo $350.59^{\circ}C$, Malas $352.41^{\circ}C$, Dillenia $364.33^{\circ}C$. The aim of this study is to determine the combustion properties of imported wood according to ISO 5660-1. And, based on the results of this study, we would proceed with further research for improving the fire safety of wood for construction.

Wearable Computers

  • Cho, Gil-Soo;Barfield, Woodrow;Baird, Kevin
    • Fiber Technology and Industry
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    • v.2 no.4
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    • pp.490-508
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    • 1998
  • One of the latest fields of research in the area of output devices is tactual display devices [13,31]. These tactual or haptic devices allow the user to receive haptic feedback output from a variety of sources. This allows the user to actually feel virtual objects and manipulate them by touch. This is an emerging technology and will be instrumental in enhancing the realism of wearable augmented environments for certain applications. Tactual displays have previously been used for scientific visualization in virtual environments by chemists and engineers to improve perception and understanding of force fields and of world models populated with the impenetrable. In addition to tactual displays, the use of wearable audio displays that allow sound to be spatialized are being developed. With wearable computers, designers will soon be able to pair spatialized sound to virtual representations of objects when appropriate to make the wearable computer experience even more realistic to the user. Furthermore, as the number and complexity of wearable computing applications continues to grow, there will be increasing needs for systems that are faster, lighter, and have higher resolution displays. Better networking technology will also need to be developed to allow all users of wearable computers to have high bandwidth connections for real time information gathering and collaboration. In addition to the technology advances that make users need to wear computers in everyday life, there is also the desire to have users want to wear their computers. In order to do this, wearable computing needs to be unobtrusive and socially acceptable. By making wearables smaller and lighter, or actually embedding them in clothing, users can conceal them easily and wear them comfortably. The military is currently working on the development of the Personal Information Carrier (PIC) or digital dog tag. The PIC is a small electronic storage device containing medical information about the wearer. While old military dog tags contained only 5 lines of information, the digital tags may contain volumes of multi-media information including medical history, X-rays, and cardiograms. Using hand held devices in the field, medics would be able to call this information up in real time for better treatment. A fully functional transmittable device is still years off, but this technology once developed in the military, could be adapted tp civilian users and provide ant information, medical or otherwise, in a portable, not obstructive, and fashionable way. Another future device that could increase safety and well being of its users is the nose on-a-chip developed by the Oak Ridge National Lab in Tennessee. This tiny digital silicon chip about the size of a dime, is capable of 'smelling' natural gas leaks in stoves, heaters, and other appliances. It can also detect dangerous levels of carbon monoxide. This device can also be configured to notify the fire department when a leak is detected. This nose chip should be commercially available within 2 years, and is inexpensive, requires low power, and is very sensitive. Along with gas detection capabilities, this device may someday also be configured to detect smoke and other harmful gases. By embedding this chip into workers uniforms, name tags, etc., this could be a lifesaving computational accessory. In addition to the future safety technology soon to be available as accessories are devices that are for entertainment and security. The LCI computer group is developing a Smartpen, that electronically verifies a user's signature. With the increase in credit card use and the rise in forgeries, is the need for commercial industries to constantly verify signatures. This Smartpen writes like a normal pen but uses sensors to detect the motion of the pen as the user signs their name to authenticate the signature. This computational accessory should be available in 1999, and would bring increased peace of mind to consumers and vendors alike. In the entertainment domain, Panasonic is creating the first portable hand-held DVD player. This device weight less than 3 pounds and has a screen about 6' across. The color LCD has the same 16:9 aspect ratio of a cinema screen and supports a high resolution of 280,000 pixels and stereo sound. The player can play standard DVD movies and has a hour battery life for mobile use. To summarize, in this paper we presented concepts related to the design and use of wearable computers with extensions to smart spaces. For some time, researchers in telerobotics have used computer graphics to enhance remote scenes. Recent advances in augmented reality displays make it possible to enhance the user's local environment with 'information'. As shown in this paper, there are many application areas for this technology such as medicine, manufacturing, training, and recreation. Wearable computers allow a much closer association of information with the user. By embedding sensors in the wearable to allow it to see what the user sees, hear what the user hears, sense the user's physical state, and analyze what the user is typing, an intelligent agent may be able to analyze what the user is doing and try to predict the resources he will need next or in the near future. Using this information, the agent may download files, reserve communications bandwidth, post reminders, or automatically send updates to colleagues to help facilitate the user's daily interactions. This intelligent wearable computer would be able to act as a personal assistant, who is always around, knows the user's personal preferences and tastes, and tries to streamline interactions with the rest of the world.

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Two Cases of Corneal Edema Due to Vaporized Amine (기화된 아민에 의한 각막부종 2예)

  • Hwang, Yousook;Cho, Yang Kyung
    • Journal of The Korean Ophthalmological Society
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    • v.59 no.11
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    • pp.1077-1081
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    • 2018
  • Purpose: We report two cases of corneal edema in patients who presented with bilateral blurry vision due to vaporized amines while working in a polyurethane processing plant. Case summary: A 28-year-old male presented with bilateral blurred vision. His work involved solidifying polyurethane liquid and he often found himself exposed to polyurethane heat and gas. Purpose: We report two cases of corneal edema in patients who presented with bilateral blurry vision due to vaporized amines while working in a polyurethane processing plant. Case summary: A 28-year-old male presented with bilateral blurred vision. His work involved solidifying polyurethane liquid and he often found himself exposed to polyurethane heat and gas. On examination, the patient's uncorrected visual acuity (UCVA) was 20/40 (right) and 30/50 (left). A slit lamp examination revealed subepithelial microbullae in both eyes. The central corneal thickness (CCT) was also increased in both eyes, measuring $698{\mu}m$ (right) and $672{\mu}m$ (left). After prescribing 0.5% moxifloxacin and, 1% fluorometholone eye drops for 3 days in both eyes, the UCVA recovered to 20/40 (right) and 20/20 (left). The CCT decreased to $644{\mu}m$ (right) and $651{\mu}m$ (left), and the microbullae improved significantly in the left eye. The second patient was a 34-year-old female who presented with bilateral decreased visual acuity while at work. She worked in a factory that produced car seat filling. Her UCVA was 20/25 (right) and 20/20 (left). The CCT by specular microscopy was $537{\mu}m$ (right) and $541{\mu}m$ (left). On slit lamp examination, both eyes demonstrated bilateral central subepithelial edema. The patient did not attend any follow-up outpatient appointments after the initial presentation. Conclusions: Exposure to vaporized amines such as polyurethane may causereversible corneal toxicityeven without direct contact. Further consideration should be given to ocular safety and protection from amine compounds in the industrial field.On examination, the patient's uncorrected visual acuity (UCVA) was 20/40 (right) and 30/50 (left). A slit lamp examination revealed subepithelial microbullae in both eyes. The central corneal thickness (CCT) was also increased in both eyes, measuring $698{\mu}m$ (right) and $672{\mu}m$ (left). After prescribing 0.5% moxifloxacin and, 1% fluorometholone eye drops for 3 days in both eyes, the UCVA recovered to 20/40 (right) and 20/20 (left). The CCT decreased to $644{\mu}m$ (right) and $651{\mu}m$ (left), and the microbullae improved significantly in the left eye. The second patient was a 34-year-old female who presented with bilateral decreased visual acuity while at work. She worked in a factory that produced car seat filling. Her UCVA was 20/25 (right) and 20/20 (left). The CCT by specular microscopy was $537{\mu}m$ (right) and $541{\mu}m$ (left). On slit lamp examination, both eyes demonstrated bilateral central subepithelial edema. The patient did not attend any follow-up outpatient appointments after the initial presentation. Conclusions: Exposure to vaporized amines such as polyurethane may causereversible corneal toxicityeven without direct contact. Further consideration should be given to ocular safety and protection from amine compounds in the industrial field.

Shelf Life Extension of Wasabi Paste Products by Addition of Citric Acid (구연산 첨가에 의한 와사비 페이스트 제품의 저장성 향상)

  • Jeong, Eun-Jeong;Lee, Hyo-Kyung;Kim, Yong-Suk
    • Journal of Food Hygiene and Safety
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    • v.34 no.4
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    • pp.354-360
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    • 2019
  • In order to extend the shelf life of Wasabi paste, the effects of citric acid were confirmed at $35^{\circ}C$ for 28 days. Citric acid-treated groups contained citric acid in amounts of 0.05, 0.10, 0.17, 0.30, and 0.40%, respectively. Quality characteristics of Wasabi pastes were determined in pH, titratable acidity, soluble solid content, color values, microbial analysis (aerobic bacteria, yeast), gas production, and content of allyl isothiocyanate. The pH and titratable acidities of Wasabi pastes added with citric acid were indicated as 4.03-5.19 and 4.23-4.82%, respectively. Soluble solid content was significantly different according to concentrations of citric acid. L values showed the highest at $50.05{\pm}0.46$. a and b values were increased during the storage period. Total aerobic bacteria and yeast counts of Wasabi pastes were decreased in a dose-dependent manner. Gas production from Wasabi pastes showed at 19.55-19.80 mL/tube after 28 days of storage. The addition of citric acid (0.3% or more) to the Wasabi paste resulted in increased storage stability.

A Study on Global Initiatives on Greenhouse Gas Reduction in the International Aviation (항공분야 기후변화 대응 현황 - 최근 ICAO 고위급회의 논의를 중심으로 -)

  • Maeng, Sung-Gyu;Hwang, Ho-Won
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.2
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    • pp.47-67
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    • 2009
  • In recent years, greenhouse gas (GHG) reduction has become high priority issue in international aviation. GHG emissions from the aviation sector only accounts for approximately 2 percent of total GHG emissions in the world. However, as with GHG gases in other sectors, it has been pointed out as a contributing factor to global warming and there is an ongoing conversation in the aviation community to establish international framework for emissions reductions. In the case of international aviation, effects of aviation activities of a State go beyond the airports and airspace of that State. This makes compiling of GHG emissions data very difficult. There are also other legal and technical issues, namely the principle of “Common but Differentiated Responsibility (CBDR)” under the United Nations Framework Convention on Climate Change (UNFCCC) and “Fair Opportunity” principle of the Chicago Convention. For all these reason, it is expected that it will not be an easy job to establish an internationally agreed mechanism for reducing emissions in spite of continuing collaboration among States. UN adopted the UNFCCC in 1990 and the Kyoto Protocol in 1997 to impose common but differentiated responsibility on emissions reductions. In international aviation, ICAO has been taking the lead in measures for the aviation sector. In this role, ICAO held the High-level Meeting on International Aviation and Climate Change on 7 to 9 October 2009 at its Headquarters in Montreal and endorsed recommendations on reducing GHG from international aviation which will also be reported to the 15th Meeting of the Conference of the Parties (COP15). Key items include basic principle in global aviation emissions reduction: aspirational goals and implementation options: strategies and measures to achieve goals: means to measure and monitor the implementation; and financial and human resources. It is very likely that the Republic of Korea will be included among the Parties subject to mandatory limitation or reduction of GHG emissions after 2013. Therefore, it is necessary for Korea to thoroughly analyze ICAO measures to develop comprehensive measures for reducing aviation emissions and to take proactive actions to prepare for future discussions on critical issues after COP15.

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Study on Fire Hazard Analysis along with Heater Use in the Public Use Facility Traditional Market in Winter (겨울철 다중이용시설인 전통재래시장 난방기구 사용에 따른 화재 위험성 분석에 관한 연구)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
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    • v.10 no.4
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    • pp.583-597
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    • 2014
  • Fire caused by heater has various causes as many as the types of heater. also, lots of damage of human life and property loss are caused, since annually continuous fire accident by heater in traditional market is frequently occurring. There are not many cases of fire due to heater in most of residential facilities such as general house, apartments, etc., because they are supplied with heating boiler, however the restaurant, store and office of the market, sports center, factory, workplace, etc. still use heater, e.g. oilstove, electric heater, etc., so that they are exposed to fire hazard. Also, when investigating the number of fire due to heater, it was analyzed to occur in order of home boiler, charcoal stove, oilstove, gas heater/stove, electric stove/heater, the number of fire per human life damage was analyzed in order of gas heater/stove, oil heater/stove, electric heater/stove, briquette/coal heater. Also, gas and oil related heater were analyzed to have low frequency, however, with high fire intensity. Therefore, this research aimed at considering more scientific fire inspection and identification approach by reenacting and reviewing fire outbreak possibility caused by combustibles' contact and conductivity under the normal condition and abnormal condition in respect of ignition hazard, i.e. minimum ignition temperature, carbonization degree and heat flux along with it, due to oilstove and electric stove, which are still frequently used in public use facility, traditional market, and, of which actual fire occurrence is the most frequent. As the result of reenact test, ignition hazard appeared very small, as long as enough heat storage condition is not made in both test objects(oilstove/electric stove), however carbonization condition was analyzed to be proceeded per each part respectively. Eventually, transition to fire is the ignition due to heat storage, so that it was analyzed to ignite when minimum heat storage temperature condition of fire place is over $500^{\circ}C$. Particularly, in case of quartz pipe, the heating element of electric stove, it is rapidly heated over the temperature of $600^{\circ}C$ within the shortest time(10sec), so that the heat flux of this appears 6.26kW/m2, which was analyzed to result in damage of thermal PVC cable and second-degree burn in human body. Also, the researcher recognized that the temperature change along with Geometric View Factor and Fire Load, which display decrease of heat, are also important variables to be considered, along with distance change besides temperature condition. Therefore, the researcher considers that a manual of careful fire inspection and identification on this is necessary, also, expects that scientific and rational efforts of this research can contribute to establish manual composition and theoretical basis on henceforth fire inspection and identification.

Risk Ranking Analysis for the City-Gas Pipelines in the Underground Laying Facilities (지하매설물 중 도시가스 지하배관에 대한 위험성 서열화 분석)

  • Ko, Jae-Sun;Kim, Hyo
    • Fire Science and Engineering
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    • v.18 no.1
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    • pp.54-66
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    • 2004
  • In this article, we are to suggest the hazard-assessing method for the underground pipelines, and find out the pipeline-maintenance schemes of high efficiency in cost. Three kinds of methods are applied in order to refer to the approaching methods of listing the hazards for the underground pipelines: the first is RBI(Risk Based Inspection), which firstly assess the effect of the neighboring population, the dimension, thickness of pipe, and working time. It enables us to estimate quantitatively the risk exposure. The second is the scoring system which is based on the environmental factors of the buried pipelines. Last we quantify the frequency of the releases using the present THOMAS' theory. In this work, as a result of assessing the hazard of it using SPC scheme, the hazard score related to how the gas pipelines erodes indicate the numbers from 30 to 70, which means that the assessing criteria define well the relative hazards of actual pipelines. Therefore. even if one pipeline region is relatively low score, it can have the high frequency of leakage due to its longer length. The acceptable limit of the release frequency of pipeline shows 2.50E-2 to 1.00E-l/yr, from which we must take the appropriate actions to have the consequence to be less than the acceptable region. The prediction of total frequency using regression analysis shows the limit operating time of pipeline is the range of 11 to 13 years, which is well consistent with that of the actual pipeline. Concludingly, the hazard-listing scheme suggested in this research will be very effectively applied to maintaining the underground pipelines.