A new simple methodology for evaluation of explosion risk in underground coal mines

The key objective of this paper is the presentation of a new risk assessment tool for underground coal mines based on a simplified semi-quantitative estimation and assessment method.In order to determine the risk of explosion of any work process or activity in underground coal mines it is necessary to assess the risk. The proposed method is based on a Risk Index obtained as a product of three factors: frequency of each individual scenario P_ucm, associated severity consequences C_ucm and exposure time to explosive atmospheres E_ucm. The influence of exposure time is usually not taken into account up to now. Moreover, the exposure to explosive atmospheres may affect factors of hazardous event probability as much as its consequences. There are many definitions of exposure to explosive atmospheres but in the case of underground coal mines the exposure is defined as frequency risk of firedamp and coal dust. The risk estimation and risk assessment are based on the developed of a risk matrix.The proposed methodology allows not only the estimation of the explosion risk but also gives an approach to decide if the proposal investment is well-justified or not in order to improve safety.     

Noise variability in underground room and pillar coal mines

Noise in an underground coal mine has dominant components generated mainly from 3 sources: (a) continuous mining machines, (b) roof bolters, and (c) cars/vehicles used to transport personnel and/or coal. Each of these 3 noise sources also has a number of well-defined sub-sources with their own noise characteristics. Sound level meters were used to collect noise data in the form of instantaneous readings and also to check calibration of other sound measuring instruments. The most useful information was obtained from a spectrum analysis of continuous digital recordings of noise over time. This paper discusses the variability or dynamics of generated noise in both frequency and time domains in relation to several independent variables related to coal extraction and transportation processes.     

Development of a relative risk model for roof and side fall fatal accidents in underground coal mines in India

A relative risk model for roof and side fall fatal accidents was developed using loglinear analysis of two-way contingency table. A few statistics such as potential fatalities (PF), relative risk of fatalities (RRF) and safety measure effectiveness (SME) were derived which can be used as key safety performance indicators of roof and side fall accidents in underground mines. The model was applied to large roof and side fall fatal accident data for a period of 6-years occurred in six companies involving 292 underground coal mines. The application reveals that effectiveness of safety measures across different locations in underground mines varies and focus is mainly concentrated in highly populated workplaces such as face. The model and the statistics developed in this study are generic and can be applied to any industrial setting.     

Collecting representative dust samples: A comparison of various sampling methods in underground coal mines

Former methods used in the U.S. to assess hazardous and explosible coal dust date back to the 1950s. As mining technologies advanced, so too have the hazards. Given the results of the recent coal dust particle size survey and full-scale experimental mine explosion tests, the National Institute for Occupational Safety and Health (NIOSH) recommended a new minimum standard, in the absence of background methane, of 80% total incombustible content (TIC) be required in the intake airways of bituminous coal mines, replacing the previous 65% TIC requirement. Most important to monitoring and maintaining the 80% TIC is the ability to effectively collect and analyze representative dust samples that would likely disperse and participate in dust explosion propagation. Research has shown that dust suspended on elevated surfaces is usually finer, more reactive, and more readily dispersible while floor deposits of dust are generally coarser and more difficult to disperse given the same blast of air. The roof, rib, and floor portions of the dust samples were collected and analyzed for incombustible content separately and the results were compared to a band sample of the roof, rib, and floor components. Results indicate that the roof and rib dust samples should be kept separate from floor dust samples and considered individually for analyses. The various experimental collection methods are detailed along with preferred sampling approaches that improve the detectability of potentially hazardous accumulations of explosible dust.     

Computer simulations help determine safe vertical boom speeds for roof bolting in underground coal mines

PROBLEM: Incident investigation reports do not usually contain enough information to aid in studying boom arm vertical speed for roof bolting machines to determine the impact that appendage speed had on an operator's risk of experiencing a contact. Laboratory experiments with human subjects are also not feasible because of safety and ethical issues. METHOD: Researchers successfully developed a three-dimensional computer model that uses virtual human simulation software as the primary means to gather contact data when the boom arm touches the operator's hand, arm, head, or leg. RESULTS: Data analysis of roof bolter simulations shows that the speed of the boom arm is the most important factor in determining the risk of an operator making contact. Regardless of other variables, contact incidents were always greater when the bolter arm was moving up, greater on the hand, and greater for the boom arm part of the machine. The reason why the subject experiences more contacts when the boom arm is moving up rather than down is that more risky behaviors occur during drilling and bolting when the boom arm is ascending. Based on the data collected, boom speeds greater than 13 in/sec result in a substantial increase in risk to the roof bolter operator of making contact. Speeds less than or equal to 13 in/sec are associated with a more modest relative risk of making contact, which represents a decrease in potential hazard. IMPACT ON INDUSTRY: The use of such information can be quite helpful in making recommendations to machine design and task procedures to reduce the likelihood that roof bolter operators will experience injury due to contact with a moving roof bolting machine's boom arm.     

地下矿山安全监测与信息化技术

论述了金属非金属矿山的安全生产现状,矿山地质灾害种类和矿山安全信息化技术,指出信息化技术的应用是解决矿山安全问题的一个重要途径.     

A risk assessment methodology for high pressure CO2 pipelines using integral consequence modelling

This paper presents a risk assessment methodology for high pressure CO₂ pipelines developed at the Health and Safety Laboratory (HSL) as part of the EU FP7 CO2Pipehaz project. Until recently, risk assessment of dense phase and supercritical CO₂ pipelines has been problematic because of the lack of suitable source term and integral consequence models that handle the complex behaviour of CO₂ appropriately. The risk assessment presented uses Phast, a commercially available source term and dispersion model that has been recently updated to handle the effects of solid CO₂. A test case pipeline was input to Phast and dispersion footprints to different levels of harm (dangerous toxic load and probit values) were obtained for a set of pipeline specific scenarios. HSL's risk assessment tool QuickRisk was then used to calculate the individual and societal risk surrounding the pipeline. Knowledge gaps that were encountered such as: harm criteria, failure rates and release scenarios were identified and are discussed.     

Pilot sample risk analysis for underground coal mine fires and explosions using MSHA citation data

After three decades of sustained continuous improvement of mine safety performances in the US, mine disasters in 2006 and 2007 compromised an excellent record and presented new challenges and vulnerabilities for the underground coal mining industry. In the aftermath of the incidents, formal investigations and new scrutiny of mine safety by the US Congress and expert study groups followed. The US Congress passed the Mine Improvement and New Emergency Response Act of 2006 (MINER Act), which mandated new laws to address the issues, including those related to mine fires and explosions from which miners must be protected. The National Mining Association-sponsored Mine Safety Technology and Training Commission report highlighted the role of risk analysis and management in identifying and controlling major hazards, such as fires and explosions. In this paper an approach is given for analyzing the risks for fires and explosions based on the Mine Safety and Health Administration citation database. Using 2006 citation data and focusing on subsystem failures, the methodology is applied to a database for a pilot sample of underground coal mines stratified by mine size and state.     

An improved methodology for assessing risk in aircraft operations at airports, applied to runway overruns

The paper addresses the need for models to assess risk at any particular airport, based on risk management principles used by the present risk management process, that use all available data on previous accidents. The case of runway overruns is taken as an example application, because new regulations require the provision of much longer Runway End Safety Areas than had previously been the norm. The paper presents models for overruns arising from both landings and aborted takeoffs. In each case models of overrun risk, of wreckage location and of the consequences are detailed. An example application of the models is then given in a hypothetical risk assessment.The models, though adding value to existing methods of assessing risk, are not as good as they could be, due to the lack of data on normal operations. It was therefore possible only to relate the rate of overruns to the rate of occurrence of the possible driving factors for a few factors where such comparable data on normal operations existed. It is recommended that effort be put into the collection of data to allow a more comprehensive analysis.     

煤矿安全从业人员心理测试指标体系研究

为了寻求有效解决煤矿安全人为事故屡禁不止问题的有效办法,探讨了煤矿作业对人提出的安全心理素质要求,对煤矿从业人员的心理因素与安全生产关系进行了工作分析与职务分析,建立了以能力与非能力因素为基本内容的心理测试指标体系,并对这一体系的科学性进行了验证.应用实践表明,该体系为从根本上解决煤矿安全问题提供了新的途径.     

基于PNN的煤矿安全生产风险综合预警研究

为加强煤矿安全生产风险预警管理,对煤矿安全生产系统风险因素进行分析,从人-机-环-管理四个方面建立了风险预警指标体系,给出了各指标的定义;提出了指标风险预警等级临界点的设置和指标警度计算方法;应用概率神经网络（PNN）构建了安全生产风险综合预警模型,通过指标风险预警等级临界点构建训练样本,并对预警模型进行了性能检验和工程应用。结果表明,基于PNN的安全生产风险综合预警模型风险识别能力强,运行速度快,计算效率高,可以进行推广应用。     

A systemic methodology for risk management in healthcare sector

The recent biomedical, technological, and normative changes have led healthcare organizations to the implementation of clinical governance as a way to ensure the best quality of care in an increasingly complex environment. Risk management is one of the most relevant aspects of clinical governance and approaches put forward in literature highlight the necessity to perform comprehensive analyses intended to uncover root causes of adverse events.Contributing to this field, the present paper applies Reason’s theory of failures to work out a systemic methodology to study risks impacting not only directly but also indirectly on patients. Also, the steps of such approach are organized around Human Reliability Assessment phases, in order to take into account the human component of healthcare systems. This framework is able to foster effective decision making about reducing failures and waste and to improve healthcare organizations’ maturity towards risk management.The developed methodology is applied to the pharmacy department of a large Italian hospital. An extensive validation in different healthcare settings is required to fully prove benefits and limitations.     

Experimental investigations on the performance of a new design of foaming agent adding device used for dust control in underground coal mines

In order to overcome the drawbacks of foam technology for controlling mine dust, an original design of foaming agent adding device was introduced, and its performance was investigated experimentally under different working flows and outlet pressures, and compared to the conventional jet adding device. The results show that the new design of the foaming agent adding device has a reasonable cavity negative pressure, does not produce cavitations, and has a lower inlet pressure demand with less pressure loss. Furthermore, it can add foaming agent at 0.5%–1.0% and regulate the proportions at this low ratio range continuously and stably, which significantly reduces the cost of controlling dust with foam. In addition, it decreases electric energy consumption and simplifies the foam system with no need for extra boosters. Besides, its effect on suppressing mine dust was investigated in the field via dust sample collections, and the results show that this new device is as effective at dust suppression as the conventional one. Therefore, it is believed that this study laid an important foundation for the widespread application of foam technology for dust control in underground coal mines.     

A methodology for assessing blast protection in explosive ordnance disposal bomb suits.

To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax. A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn.     

Classification technique for danger classes of coal and gas outburst in deep coal mines

In this investigation a new classification technique based on artificial neural network (ANN) and exponent evaluation method (EEM) has been developed to classify the danger classes of coal and gas outburst in deep mines. A weight computing model of mutual affecting factors is derived from backward algorithm of ANN (BA-ANN), which diminishes the influence of factitious factor, the environment factor and the time factor to the weight. The BA-ANN model is used for modeling the correlation between danger class and 12 affecting factors of coal and gas outburst and calculating weights of interconnection factors, which performs very well. In order to classify danger classes in a daily routine, the EEM with the well trained weights which are from BA-ANN, is performed in a deep mine. The case study shows that this new technique is useful to classify danger classes with quick and accurate computation. Moreover, the weight computing model of BA-ANN can be extended to other safety issue in different fields as well.     

全国煤矿安全电话会议强调坚决关闭不安全的小煤矿遏制重特大事故发生

5月 2 2日 ,国家安全生产监督管理局、国家煤矿安全监察局召开全国煤矿安全电话会议 ,国家安全生产监督管理局、国家煤矿安全监察局局长张宝明在会上作了重要讲话。会议分析了今年以来煤矿安全生产形势 ,通报了近期发生的几起特大事故 ,针对目前煤矿安全生产上存在的突出问题 ,提出下一步安全生产工作的要求。　　今年以来 ,煤矿安全生产基本稳定 ,但进入 4月份以后 ,重特大事故多发。据统计 ,1季度全国煤矿共发生一次死亡 3人以上重大事故 77起、死亡 5 73人 ,但是从 4月 1日～ 5月 16日的一个半月时间 ,全国煤矿就发生一次死亡 3人以上重…     

Probability of death,disability, and restricted work activity in United States underground bituminous coal mines, 1975–1981

This study examined relationships between mine and miner characteristics and severity of 82,945 underground bituminous coal mine injuries using logistic regression techniques. Injuries were classified as severe if they resulted in death, disability, or restricted work activity. Supervisory and maintenance personnel were found to have fewer chances of severe injuries than “all other” job classifications. A shaft or slope had a lower association with severe injuries than the face. The probability of a severe injury increased each succeeding year from 1975 through 1981. Mining method was not related to degree of injury. Older miners had the same probability of severe injuries as younger miners. Weeks of experience in mining, on a particular job, and in a specific mine were not related to severity of injuries. Mobile equipment operators had the same chance of severe injuries as miners in “all other” job classifications. Accidents at intersections and “other” locations were as likely to produce severe injuries as those at the face. Elapsed shift time prior to an injury was not related to injury severity. The implications of these findings are discussed and recommendations made for future research.     

安全高效矿井设计探讨

矿井设计阶段要准确掌握矿井的开采条件,针对存在的危险有害因素在工程上采取必要的措施。优化矿井的开采巷道,合理选择开采工艺、通风系统等,促进矿井生产高效,为安全高效矿井建设奠定条件。     

A new practical approach to risk management for underground mining project in Quebec

The mining industry worldwide is currently experiencing an economic boom that is contributing to economic recovery and social progress in many countries. For this to continue, the mining industry must meet several challenges associated with the start-up of new projects. In a highly complex and uncertain environment, rigorous management of risks remains indispensable in order to repel threats to the success of mining.In this article, a new practical approach to risk management in mining projects is presented. This approach is based on a novel concept called “hazard concentration” and on the multi-criteria analysis method known as the Analytic Hierarchy Process (AHP). The aim of the study is to extend the use of this approach to goldmines throughout Quebec. The work is part of a larger research project of which the aim is to propose a method suitable for managing practically all risks inherent in mining projects.This study shows the importance of taking occupational health and safety (OHS) into account in all operational activities of the mine. All project risks identified by the team can be evaluated. An adaptable database cataloguing about 250 potential hazards in an underground goldmine was constructed. In spite of limitations, the results obtained in this study are potentially applicable throughout the Quebec mining sector.     

A fuzzy model for assessing risk of occupational safety in the processing industry

Managing occupational safety in any kind of industry, especially in processing, is very important and complex. This paper develops a new method for occupational risk assessment in the presence of uncertainties. Uncertain values of hazardous factors and consequence frequencies are described with linguistic expressions defined by a safety management team. They are modeled with fuzzy sets. Consequence severities depend on current hazardous factors, and their values are calculated with the proposed procedure. The proposed model is tested with real-life data from fruit processing firms in Central Serbia.