Search Documents

Objective: To devise a passive means to detect overheating insulators on mine trolley/track haulageways.

Aug 1, 1998

Objective: The Roof Monitoring Safety System (RMSS) provides a first step in roof behavior awareness. By understanding and measuring roof movement in an underground mine, the potential for injuries or fatalities to mine workers from fall of ground can be lessened. Also, officials at an underground mine with a history of data on roof movement are better prepared to make a decision on remedial actions if falls of ground become a problem. The RMSS provides a safer, simple, and inexpensive means for measuring roof movement.

Aug 1, 1998

By F. N. Kissell, H. K. Sacks

This study examines the accuracy of area sampling for measuring the dust exposure of mining machine operators in coal mines. The specific objective of this research was to find locations where an area sampler might work better than earlier studies have indicated. The results show that fixed-location area sampling cannot accurately predict the dust exposure of a machine operator, even when the best fixed location is sought, the fixed location is quite close to the operator and the bias due to the dust concentration gradient is corrected. Industrial hygienists have known for many years that area sampling is unsuitable for measuring air contaminant exposures in the workplace. Near contaminant sources, the dilution air and the contaminants are not evenly mixed. Therefore, when workers are near contaminant sources, exposure measurements must be taken from the worker's breathing zone to be accurate

By Launa Mallett

This paper introduces a method for teaching workers to communicate necessary information when giving or receiving emergency warning messages. Research has shown that when an emergency occurs, people may not get the information they need to take appropriate action. Interviews conducted with 48 underground coal miners who had escaped mine fires revealed that the warning information provided was inadequate. In some cases, sufficient information was not provided to the endangered miners. At other times, miners failed to ask for information they needed to plan and execute effective escapes. Researchers from the NIOSH Pittsburgh Research Laboratory have been studying the content of emergency warning messages and have developed an emergency communication protocol. A training intervention that presents the protocol and related mental cues is being evaluated for effectiveness in improving the content of emergency messages. In this paper the protocol is presented and the training package described. The evaluation procedures and a summary of the analyses conducted to-date are also provided. The training package was developed for use with underground coal miners, but could easily be modified for emergency communications training in other settings.

Jan 1, 2000

By Peter G. Kovalchik, Lawrence W. Scott, Thomas H. Dubaniewicz, Frank T. Duda

Overheating of electric cables on shuttle cars has long been recognized as a cause of premature insulation failure leading to shock and electrocution. Use of cable reels on shuttle cars can cause excessive heat build up which, in turn, causes the cable insulation to soften and become easily damaged This heat-softened insulation reduces the life of the cable. Repeated cycling of a cable in this manner can cause premature aging of the insulation; it becomes bridle, cracks and allows electrical leakage paths to farm. These leakage paths provide the opportunity for shock and electrocution to occur if miners come in contact with the damaged section of cable. It is imperative that cable operating temperatures be maintained at safe thermal limits. This paper discusses a research project conducted by the National Institute for Occupational Safety and Health, Pittsburgh Research Center to determine dynamically the conductor temperature of reeled shuttle car cables using fiber optics technology. The research portrays typical shuttle car loading cycles (both current and time cycles). Root-mean-square current loading is calculated based on the results. The thrust of this effort is to provide the scientific basis for ampacity derating factors specifically for mine machinery using reeled cables This information will reduce the probability of electrical hazards from reeled cables

By C. J. Johnson, C. J. Bise

"The occurrence of Coal Worker's Pneumoconiosis (CWP) ·has been potentially linked with several characteristics of coal such as rank, volatility, percent content of ash and non-coal components, quartz content, and the presence of several trace elements. According to the National Research Council, numerous epidemiological Studies: indicate that the incidence of CWP varies significantly with the composition and/or the concentration of the coal mine dust.Although advances in dust suppression techniques have markedly reduced respirable dust levels in underground coal mines, the National Research Council has concluded that chemical characteristics of respirable dust from different coal seams should be studied. With this objective in mind, research has been conducted in underground coal mines located in the eastern and mid-western United States, and in the laboratory to characterize the elemental composition of mining-generated airborne dust and laboratory-generated dust derived from samples taken from these mines. The goal of the research is to determine if a relationship exists between mining-generated and laboratory-generated dust from the ·same mine. Results of this research will be presented. ,"

Jan 1, 1988

By E. V. Cilento, K. A. DiGregorio, R. C. Lantz

This laboratory has developed a sensitive electro-optical method to quantify the initial rate (R) and total amount.(MAX) of superoxide (SO) produced by single pulmonary alveolar macrophages (PAM). The method uses a microscope to visualize PAM in culture, and to video record the images during the time the cells produce SO. MAX and R are calculated from measurement of temporal changes in optical density in the images due to precipitated diformazan formed by the reaction of SO, produced by each PAM, with nitroblue tetrazolium present in the culture medium. To date, values of Rand MAX, measured due to adherence of PAM to the dish, have been compared to values obtained when quartz, coal mine dust (CMD), and kaolin were added to the medium (in vitro). R and MAX have also been calculated for PAM lavaged from animals exposed to quartz and CMD in the WVU Inhalation Facility. Presently, experiments are being done using serum which permits PAM to be restimulated by different dusts to help establish a dose response effect, and a means to study the effects of lung surfactant on modifying the toxicity of inhaled dusts. Long term, this methodology should provide useful insight· into establishing the role SO plays in the phagocytosis of inhaled dusts and bacteria, in PAM dysfunction, and in lung diseases such as pneumoconioses. Supported by the Department of the Interior's Mineral Institute Program administered by the Bureau of Mines through the Generic Mineral Technology Center for Respirable Dust (G1135142).

Jan 1, 1988

By C. W. Lee

"Introduction of diesel engines in underground mines may generate severe health hazards associated with exhaust contaminants. One of the most important parameter in determining the optimal air quantity for hazard reduction is the exhaust dispersion. Through analyzing the exact solution of the diffusion equation and its approximation by finite difference method(FDM) , this paper aims at doing a fundamental research to find an efficient dispersion model suitable to the domestic mines. Diffusion coefficients are likely to be small in the underground airways with high ventilation resistance. This makes concentration profiles similar to the convection-based step functions. It is the case for fixed as well as moving engines. Concentration estimation by exact solution is almost impossible in the case of either a single engine moving at a variable speed or the existence of multiple engines. Application of FDM to the diffusion equation including turbulent dispersion results in the various problems; unstable concentration profiles depending on the engine location, nuctuating concentrations near the engine, and overestimation of the dispersion region of which error grows with waning diffusion coefficient.Convection-based dispersion model is found to fit well for dynamic simulation of exhaust dispersion from multiple diesel engines in the airways showing low diffusion coefficients. Its suitability is more likely in the regions with frequent equipment passage. Published"

Nov 1, 1995

Dec 1, 2007

Develop an easy-to-use, reliable, resin-grouted cable support system capable of being installed as primary and secondary roof support in coal mines.

Jan 1, 1994

By F. C. Trutt, J. Sottile, J. L. Kohler

Presented in this paper is a theoretical review of the relationships that should exist between electrical winding parameters and the mechanical vibration of a-c machine elements under normal and faulted operating conditions. Also included is data from an experimental study that relates stator vibration and bearing vibration to selected winding faults in a synchronous machine. Consideration of these results indicates a significant relationship between electrical deterioration and mechanical vibration and thus provides the motivation for additional study and a basis for future applications.

By Frederick C. Trutt, Jeffery L. Kohler, Joseph Sottile

Condition-based maintenance (CBM) of industrial equipment is generally recognized as being the most cost-effective means for improving equipment availability. However, prerequisite to successful implementation of CBM is a reliable detector of failing components. One such detector, termed the effective negative-sequence impedance, had previously been identified as an indicator of induction motor stator winding degradation. However, a limitation of this detector is that it does not change in a predicable manner under certain motor operating conditions. This paper presents an experimental investigation of an improved technique for on-line detection of induction motor stator winding degradation. The paper begins with a brief description of the detectors, followed by a detailed description of the experimental setup, the experiments conducted, and results.

By Launa Mallett, Charles Vaught, Jr. Brnich

This paper introduces a technique for incorporating employee participation into the prevention component of a contingency plan. Companies sometimes focus so much energy on response that they forget to put resources into the basics of emergency prevention. The training program discussed here was designed to make employees part of the prevention system. Examples of training materials from the program are provided, a sample method for introducing risk assessment to employees is shown, and a strategy to address limited training time using short videos is explained. Methods for tailoring the training to any worksite and for specific risks are also included. The program is being designed and tested by the Pittsburgh Research Laboratory/NIOSH and employees of an underground coal mine. Examples are taken from the implementation of the program at the mine during the summer and fall of 1998. Results of the program evaluation and lessons learned during the implementation are discussed.

By R. V. Ramani, A. S. C. Owili-eger

The Methane Generator program is a part of the Internal Environ¬mental Sub-system of the Master Design Simulator (MDS). All the sub¬systems of the MDS are controlled and activated by the main program as required. The data requirements for the Methane Generator are supplied by the Geology and Reserves sub-system through common storage. Figure 6 shows the information flow between the Methane Generator and other systems of the MDS. It should be noted that the Methane Generator can also function independently as was described under model application. AREAS OF MISSING INFORMATION In any numerical analysis, the accuracy of the solution depends entirely upon the data available. In gas flow problems, parameters that constitute basic model input data are rock porosity, medium permeability, reservoir pressure and initial reservoir pressure dis¬tribution. Unfortunately, however, most of these characteristics are not available for a lot of coal seams. The need for actual field data cannot, therefore, be adequately emphasized here.

Jan 1, 1974

By O. C. Blade, E. L. Garton

Louisiana is one of the major oil-producing States of the country. Commercial production of crude oil in the State began in 1902 and has increased to an estimated output of 157,409,000 barrels in 1945, which is the maximum production up to this time and places the State fourth in the nation. The cumulative production for Louisiana through 1944 is 1,544,481,000 barrels, and, adding the output for 1945, the total to January 1, 1946, is 1,681,890,000 barrels. Data on annual production of crude oil in Louisiana and tentative statistics for 1945 are given in table 1. The large production of crude oil in Louisiana and the present trend to utilize petroleum in accordance with its general characteristics make it increasingly important to present analytical data for crude oils. This report is the fifth of a series presenting such data obtained on crude oils from Louisiana according to the procedure used by the Bureau of Mines. Individual analyses are given for 82 samples from 64 fields; many of the samples are from recently discovered fields, and some are from new producing formations.

Dec 1, 1946

By T. M. Barton

This paper presents several case studies in which a mechanics-based boundary-element program is used to back-calculate the surface subsidence associated with various panels at several northern Appalachian coal mines. The program used in this case study is called LAMODEL, which incorporates a frictionless, laminated overburden into a general-purpose displacement-discontinuity code primarily designed for calculating the stresses and displacements in coal mines or other thin-seam or vein-type deposits. In this paper, the program is used to calculate both the underground convergence and the resulting surface subsidence at five longwall panels and a room-and-pillar section. The fitted subsidence from the model is compared with the field measurements and analyzed. The results from this work show that the LAMODEL program is not as accurate as available empirical subsidence-predictive methods: the expected correlation between the geology and the optimum input parameters is not evident. However, for a mechanics-based program, LAMODEL does provide moderately accurate subsidence calculations, and it is one of a few programs that can even attempt to practically calculate both underground stress and convergence and the resulting surface subsidence.

By Launa G. Mallett, Charles Vaught

This report is intended to help mine safety trainers better prepare to teach the influx of new underground coal miners who are entering the industry. This is done by identifying two different approaches to instruction and discussing the ways they may affect how well prepared new hires are to deal with a dynamic and hazardous workplace. One approach is based on the use of a syllabus. Those using a syllabus are more likely to rely on lecturing or direct instruction. This is a good way to get across factual information, but does not provide a context within which miners can fit the discrete facts so that they form an integrated whole set of concepts, principles, and skills. The other approach is based on the use of a curriculum. Those using a curriculum may be more likely to help miners integrate concepts and skills that give them an overall picture of the complex mining environment and how they fit into the workplace. This will better prepare them for the decision-making and problem-solving activities that will help them work safely and productively

Jan 1, 2008

By Lisa Steiner

Almost every process has a predecessor, and studying the predecessor helps to define needs and shortcomings to be addressed in the new design. It also suggests what information is needed by the users in order for them to be able to operate safely and effectively. The end users of a system can provide important feedback to better evaluate the current and proposed designs. When new technology is introduced into a system, mishaps may occur before it is realized that human-system interactions were not considered adequately in the design process. A systematic methodology to evaluate the causes of these injuries and to develop remedial recommendations can enhance safety. This paper illustrates how such an approach was used to assess remote machine operation in underground coal mines. The dynamic work environment of underground mining with its unpredictable geologic anomalies can result in numerous hazards. Many of these hazards, including mine roof collapse, occur near the working face where coal is being extracted. The face area is also where the most intricate interactions of people and equipment occur. For these reasons, a high priority has been placed upon minimizing hazards to the workers at the face. A remote control operation was introduced to provide a safer working distance from these hazards. As the remote control technology began to be widely used for extended cut mining operations, new issues became evident. It was essential to develop mechanisms for mines to evaluate these issues in order to predict and reduce injuries. Mining methods and equipment changes must allow for the ability of workers to adapt to changes in their dynamic mining environment. Consideration should be given to how the worker will use familiar information to make decisions in now unfamiliar situations. There will be both intended and unintended consequences [Merton, 1949]. Designers try to anticipate and eliminate surprises, but it is impossible to eliminate them all. How, then, will the new system affect the tasks to workers which are currently accustomed? As suggested below, this question may be addressed and more of the unintended outcomes predicted with a planned design process which includes strong human factors input to determine interactions and behaviors of participants.

Jan 1, 2005

By James E. Mills

Coal, in the process of mining, transportation, and handling and on exposure to the weather, is subject to more or less disintegration. This disintegrated coal is usually called "slack" and amounts often to a considerable percentage of the lump coal produced in the mines. If this slack coal is wasted the loss so occasioned ranges from 5 to 50 per cent, or even more, of the total coal mined. It is therefore clear that the utilization of this waste slack coal becomes a serious economic consideration. When the coal is suitable for the production of coke, the utilization of the slack presents no difficulty, as it is in demand for that purpose. If the coal does not produce good coke, but cakes rather readily, the slack can be used for boiler purposes, as it fuses together more or less quickly, and burns on the furnace grate without great loss. Coal that cakes less readily can be burned on grates of special construc- tion. When so used it is more troublesome to handle, and the waste is greater than when lump coal is used. Consequently the price of much of the slack coal for fuel purposes ranges considerably lower than that of the lump coal from the same mine. The full value of this slack coal as fuel can be realized by first form- ing the coal into a coherent mass or briquet, such briquets, when of good quality, being equal to or of greater value than the original

Jan 1, 1911

By S. H. Denny

"As the result of the work of an efficient safety organization, the Midwest Refining Co. at its various operations and particularly in the Salt Creek field has been able to show a definite accident reduction. Lost-time accidents during the past year have been reduced to a small number as compared with previous years, and infection cases have been almost eliminated.The accident-prevention work of the Midwest Refining Co. is in charge of the department of industrial relations, with a director as the administrative head; two safety men handle the work directly at Midwest, Wyo. A competent medical staff with a well-equipped hospital at Midwest is also an important factor in the prompt and proper treatment of injured persons when an employee is injured, he is given first-aid and then taken to the hospital with minimum delay.About 1,450 persons are employed in the 4 departments (production, gas, pipe lines, and electrical) and in the 34 districts of the Midwest Refining Co. The work at Midwest spreads over a considerable area, and new drilling operations, pipe work, and similar activities require the services of many small gangs of workers. Complete supervision, of each job, whether shall or large, is possible through the large number of superintendents, foremen, and gang pushers employed; thus, there are 20 superintendents, 78 foremen, and 115 gang pushers. The largest number of men under any one toss is approximately 15, and it is probable that much of the good safety record is due to this intensive supervision. These company officials, including the gang pushers, have been impressed with the idea that it is their duty to see that the men under them do not get hurt; the responsibility of instructing new employees in safety practices is placed directly upon them. Monthly meetings of the field officials, including superintendents, foremen, and gang pushers, and as far as possible the men, of each district are held with the safety engineer. Both officials and men are encouraged to bring up for discussion any practice or proposals looking to the changing of any conditions that will"

Apr 1, 1928