• Smart Structures and Systems
• /
• 제30권5호
• /
• pp.433-446
• /
• 2022

Despite efforts to reduce unexpected accidents at confined construction sites, choking accidents continue to occur. Because of the poorly ventilated atmosphere, particularly in long, confined underground spaces, workers are subject to dangerous working conditions despite the use of artificial ventilation. Moreover, the traditional monitoring methods of using portable gas detectors place safety inspectors in direct contact with hazardous conditions. In this study, a long-range (LoRa)-based wireless safety monitoring system that features the network organization, fault-tolerant, power management, and a graphical user interface (GUI) was developed for underground construction sites. The LoRa wireless data communication system was adopted to detect hazardous gases and oxygen deficiency within a confined underground space with adjustable communication range and low power consumption. Fault tolerance based on the mapping information of the entire wireless sensor network was particularly implemented to ensure the reliable operation of the monitoring system. Moreover, a sleep mode was implemented for the efficient power management. The GUI was also developed to control the entire safety-monitoring system and to manage the measured data. The developed safety-monitoring system was validated in an indoor testing and at two full-scale water pipeline construction sites.

• 터널과지하공간
• /
• 제29권1호
• /
• pp.30-37
• /
• 2019

해외의 일부 광업 선도국에서는 정량적인 설계지침을 제시하거나 별도의 광산 갱도 설계지침을 개발하여 배포함으로써 지하광산 운영 시 대규모 인적 물적 피해로 이어질 가능성이 높은 낙반 및 붕락 재해의 발생을 최소화하기 위해 노력하고 있다. 국내의 경우에는 광산안전기술기준 등 광산개발 관련 지침을 통해 근로자 사고 방지를 위한 안전수칙과 작업지침을 제공하고 있으나, 갱도설계에 대한 부분에서는 정성적이고 불명확한 시공 지침만을 제공하는 데에 그치고 있다. 최근 국내 환경규제 및 천부 자원 고갈로 인해 광산이 점차 심부화되고 있는 추세이며, 갱도의 안정성을 확보하기 위해 정량적인 설계 규격을 제공할 수 있는 전문적이고 체계적인 광산 갱도설계 지침에 대한 수요가 증가하고 있다. 이에 따라 본 원고에서는 국내외 광산 갱도설계 실태와 연구동향 및 현행 설계지침에 대한 현황 조사를 통해 국내 갱도 설계지침 개발을 위한 사전연구를 수행하였다.

• Safety and Health at Work
• /
• 제9권2호
• /
• pp.149-158
• /
• 2018

Background: Work comfort studies have been extensively conducted, especially in the underground and meteorological fields resulting in an avalanche of recommendations for their evaluation. Nevertheless, no known or universally accepted model for comprehensively assessing the thermal work condition of the underground mine environment is currently available. Current literature presents several methods and techniques, but none of these can expansively assess the underground mine environment since most methods consider only one or a few defined factors and neglect others. Some are specifically formulated for the built and meteorological climates, thus making them unsuitable to accurately assess the climatic conditions in underground development and production workings. Methods: This paper presents a series of sensitivity analyses to assess the impact of environmental parameters and metabolic rate on the thermal comfort for underground mining applications. An approach was developed in the form of a "comfort model" which applied comfort parameters to extensively assess the climatic conditions in the deep, hot, and humid underground mines. Results: Simulation analysis predicted comfort limits in the form of required sweat rate and maximum skin wettedness. Tolerable worker exposure times to minimize thermal strain due to dehydration are predicted. Conclusion: The analysis determined the optimal air velocity for thermal comfort to be 1.5 m/s. The results also identified humidity to contribute more to deviations from thermal comfort than other comfort parameters. It is expected that this new approach will significantly help in managing heat stress issues in underground mines and thus improve productivity, safety, and health.

• Radiation Oncology Journal
• /
• 제23권4호
• /
• pp.243-252
• /
• 2005

목적: 지하에 위치한 방사선치료 관련시설 내의 실내공기 질은 근무자뿐만 아니라 장기간 치료받는 환자들의 건강에도 중요하다. 저자들은 근무자들의 빌딩증후군 증상유무의 확인과 함께 실내공기 질과 관련된 여러 인자들을 측정, 분석하여 그 원인을 찾고 해결책을 제시하고자 하였다. 대상 및 방법: 근무자들을 대상으로 자각증상 및 근무환경 인식과 관련된 설문조사를 하였고, 예비조사를 바탕으로 실내공기 질과 관련된 항목들(온 습도, 미세먼지, 이산화탄소, 일산화탄소, 포름알데히드, 총휘발성유기화합물, 라돈)에 대해 근무자들이 주로 머무르는 지역들을 중심으로 일정기간 측정하였다. 아울러 환기(공조) 시스템의 효율 및 주변 환경에 대한 평가를 동시에 진행하였으며, 실외공기와의 비교평가를 위해 1층(실외)에서도 같은 항목들을 측정하였고, 측정 자료들은 국내외 환경관련 기관들의 권고 수치를 기준으로 각각 평가하였다. 결과: 설문조사에서 근무자들은 악취, 습도, 먼지 등에 대해 불만족을 보였으며, 근골격계 증상, 신경계 증상, 점막 자극 증상 등을 주로 호소하였다. 대부분의 실내공기 질 관련 항목들은 기준치를 넘지 않았으나 총휘발성유기화합물 수치가 기존 미국 사무실 측정 수치에 비해 $3{\sim}4$배 높게 나왔다. 환기 횟수나 환기량에서는 문제가 없었으나 실외공기 유입구와 실내공기 배출구의 위치 문제로 인해 오염된 공기의 유입 가능성이 있었다. 총휘발성유기화합물을 배출할 수 있는 현상액과 같은 화학물질의 관리에 주의가 필요했으며, 오염된 공기의 재유입 문제를 해결하기 위해 환기 시스템의 위치조정이 시급한 상황이었다. 결론: 저자들은 실내공기 질에 대한 평가에서 일부 화학물질 및 부적절한 환기 시스템으로 인해 근무자들이 주관적인 증상을 호소할 수 있음을 확인하였다. 지하 공간에서 장시간 거주하는 근무자들의 근무여건 개선과 함께 면역저하를 동반한 환자들의 건강관리를 위해 실내공기 질에 대한 평가는 반드시 필요하며, 그 자료를 바탕으로 향후 방사선종양학과의 설계나 기존 시설의 환경개선 등에 적극적으로 이용해야 하겠다.

• 한국지리정보학회지
• /
• 제20권4호
• /
• pp.39-54
• /
• 2017

본 연구는 1998년부터 2010년까지 84개 시군에 대한 지하시설물 전산화가 완료되고 2011년부터 신규로 배관공사가 이루어지거나 기존관로 유지보수 갱신 배관공사에 대하여 2010년 개정된 국토지리정보원 고시 공공측량작업규정 제134호의 지하시설물도 작성시기에서 정확도 확보를 위하여 되메우기 전 노출관로에 대한 위치 및 심도측량으로 지하시설물도를 작성하게 되어있다. 실시간으로 작성하게 되어 있는 지하시설물도의 작성기법에 대하여 기존 방식과 대비 더욱 효율적이면서 부가가치가 높은 방식으로써 예산절감효과를 도출하여 현업에 적용 할 수 있는 응용기술을 모색하는데 그 목적이 있다. 최적화 된 드론영상자료를 기본으로 지상기준점 배치가 최대한 균등하게 분포되도록 이미지 프로세싱을 수행하여 오차범위에서 벗어난 지상기준점을 소거하고 재프로세싱 하여 양질의 성과를 도출함으로써 드론방식의 지하시설물도를 작성, 허용오차 범위 내에서 수용되는 검증결과를 수립하고, 프로세싱방법의 표준화가 될 수 있는 새로운 작업방법을 제시하고자 한다.

• 한국안전학회지
• /
• 제10권3호
• /
• pp.96-105
• /
• 1995

The better industry develops, the more spaces need but in the limited area. Most building become larger and more complicated if the more spaces need in the constant area. And this leads to do underground work in long period generally six(6) months for 6 basement stories due to the selection of TOP DOWN technique. Working environment in this underground area can be problems and should not be overlooked, because air quality in underground spaces become quickly worse. Recently, department name to control construction safety has been changed to ENVIRONMENT & SAFETY TEAM from SAFETY TEAM. This means that it is very important to control against environmental condition at site so much. Overall construction work as well as underground work should conform to the requirement of working environment, particularly against inhabitants around the construction area. Strut protection, one of earth protection method, in case to 40m long strut may become weaker due to thermal stress or its longitudinally compressive strain and the another one, earth anchor protection may not be applied to the site In case of encroaching on vertical underground borderline because of regulation to prohibit it. It is necessary that TOP DOWN technique should be introduced in order to solve the external and internal problem of the site such as difficulty level of the work, potential danger with excavating depth, and shortening workperiod. It is needed that improving way of working condition should be shown and simplified computer simulation program should be also provided for checking pollution level & ventilation, excluding of lighting problem here. Results measured with conformance to the Regulation for Working Environment Measurement, enforced by Ministry of Labor have been applied to the computer program developed here. Sample air taken at unit workplace which was considered as exposing condition of pollutant at breathing point and within a range of behavior of the workers, Identified exposing group in underground work, using Moded Flow Life Finally, three types of ventilation system, type I with blower & ventilator, type II natural supply with mechanical ventilation system, and type I mechanical ventilation with Drivent Fan Unit System are selected for this study.

• Safety and Health at Work
• /
• 제10권4호
• /
• pp.461-469
• /
• 2019

Background: Collisions involving workers and mobile machines continue to be a major concern in underground coal mines. Over the last 30 years, these collisions have resulted in numerous injuries and fatalities. Recently, the Mine Safety and Health Administration (MSHA) proposed a rule that would require mines to equip mobile machines with proximity detection systems (PDSs) (systems designed for automated collision avoidance). Even though this regulation has not been enacted, some mines have installed PDSs on their scoops and hauling machines. However, early implementation of PDSs has introduced a variety of safety concerns. Past findings show that workers' trust can affect technology integration and influence unsafe use of automated technologies. Methods: Using a mixed-methods approach, the present study explores the effect that factors such as mine of employment, age, experience, and system type have on workers' trust in PDSs for mobile machines. The study also explores how workers are trained on PDSs and how this training influences trust. Results: The study resulted in three major findings. First, the mine of employment had a significant influence on workers' trust in mobile PDSs. Second, hands-on and classroom training was the most common types of training. Finally, over 70% of workers are trained on the system by the mine compared with 36% trained by the system manufacturer. Conclusion: The influence of workers' mine of employment on trust in PDSs may indicate that practitioners and researchers may need to give the organizational and physical characteristics of each mine careful consideration to ensure safe integration of automated systems.

• 한국안전학회지
• /
• 제37권4호
• /
• pp.58-62
• /
• 2022

Metro subway construction is a field that requires a great deal of professional manpower. The aging of professionals has a negative impact on both productivity and health, owing to poor working environments, heavy lifting, underground work, and other factors. To address this issue, the government is progressively revising and enforcing health management law and regulation in the construction industry. Thus, the job stress and work ability of many professional subway construction workers, who are rapidly aging, are being analyzed to ensure their safety and improve their health. In this study, the Macpa stress index of Busan Metro Subway construction workers from Sasang to Hadan line was measured by using a Macpa measurement machine, and a work ability survey was conducted by using the questionnaire that was developed by the FIOH. The independent variables were age, years of service, job position, employment type, and occupation. While, the dependent variables were the Macpa stress index and work ability. The Kruskal-Wallis test was used because it was difficult to assume that the statistics of this study represented a normal distribution. The results showed that age, job position, and employment type affected Macpa stress index and revealed that as the age of the workers increased, their stress levels increased as well. Additionally, job position and employment type affected the work ability of the metro subway construction workers. In terms of job position, the technical engineers were under a lot of stress, and whereas the managers had the best work ability. The technical engineers were more stressed than the other workers because of a poor working environment. In terms of employment type, daily workers were under more stress and lower work ability than others.

• 한국환경보건학회지
• /
• 제17권1호
• /
• pp.32-38
• /
• 1991

Airborne suspended particulate concentration in drilling sites of underground coal mines in Taebaek area was evaluated. And respirable coal dust exposure level was evaluated. Airborne suspended particulate mass include total suspended particle(TSP) and thoracic particle(TPM). TSP (by open-face filter holder) and TPM(by elutriator) concentration were determined by low volume air samplers. Personal air samplers were attached to the coal workers including drillers, coal cutters, and their assistants. Normality and log-normality of TSP, TPM, and respirable dust(RPM) concentration were tested by Kolmogorov-Smirnov one-sample test. Differences of means of TSP, TPM, and RPM concentration were tested by paired t-test. Relation between TSP, TPM, and RPM with pairs were tested by regression test and Pearson's correlation.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 C
• /
• pp.1159-1162
• /
• 1998

The induced voltage of underground pipelines caused by the stray current not only do harm to workers and instruments. but also cause big accident such as gas explosion. The AC stray current is mainly produced by the grounding system of the 22.9kV distribution power system and the DC stray current is mainly produced by the subway system. The mechanism of AC and DC induction, stray current failure examples of domestic and foreign countries and the countermeasure of the AC and DC induction are described.