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By R. H. Grau, S. B. Robertson, J. Dolgos, T. P. Mucho

The National Institute for Occupational Safety and Health (NIOSH) has developed a computer program called the Air Quantity Estimator (AQE). The purpose of the program is to provide a starting point for estimating the air quantity needed to dilute diesel particulate matter (DPM) in an underground large opening mine, albeit taking into account various input assumptions. The AQE estimates the total air quantity needed to dilute DPM emissions that enter the main airstream of the mine to current statutory levels. It helps operators pinpoint vehicles that are high DPM contributors. In addition, it allows the user to make “what if” scenarios by varying the input parameters to achieve the most efficient and practical ventilation system. The AQE is a stand-alone software program that does not require any type of spreadsheet software. Engine data must be known or estimated with some accuracy and assumptions must be made in order to limit the variability of the program output. Program calculations and two case studies, for validation purposes, are included in this report. It should be noted that the program does not ensure adequate face ventilation and personal exposure compliance.

By M. A. Trevits

During the time period from 1990-2007, 1601 reportable fires occurred in the U.S. mining industry (an average of 89 fires per year). The leading causes of U.S. mine fires were flame cutting and welding operations, frictional heating and ignitions, electrical shorts, mobile equipment malfunctions, and spontaneous combustion. The fact that mine fires continue to occur with an alarming regularity reinforces the importance of recognizing and eliminating the potential hazards and the overall need for improved fire control and suppression technology to ensure the best possible outcome during a mine fire. The National Institute for Occupational Safety and Health (NIOSH) is conducting an evolving comprehensive program of research that is addressing mine fire prevention, detection, management and suppression. This paper presents a summary of recent research accomplishments and provides an overview of the next phase of the NIOSH mine fire research program.

Jan 1, 2008

By Larry L. Wischhoefer

The Automated Breathing Metabolic Simulator (ABMS) is a versatile machine capable of performing almost any physiologically appropriate respiratory simulation. The first ABMS was delivered to the Bureau of Mines by IBM in 1973. Since then efforts have been made to refine the systems and components which make up the ABMS including the Breathing Simulator Module (BSM), Gas Analysis Module (GAM), and Supervisory Controller (SC)-each of which are also capable of stand-alone operation. Since September 1980, Reimers Consultants has been testing and modifying the ABMS and its components in order to improve the equipment and to develop simulation criteria and parameters. Changes have been made to the Phase I Design Plan and Performance Specifications; future improvements based on current experience are recommended; and test results of full scale testing conducted by Reimers Consultants in November 1983 on several types of breathing apparatus are reported and illustrated.

Jan 1, 1984

During the initial portion of the contract several alternative designs were considered, as set out step by step in the monthly reports. The conclusions reached during this period were - to use on INTERDATA Model 70 as the system minicomputer - to drop the idea of multiplexing and digitizing the inclinometer outputs downhole due to the greater complexity and cost that that alternative would imply - to use a multitasking software monitor to enable synchronization of the several tasks that the system would have to perform simultaneously - to use a common controller for all I/0 devices except those which were available off the shelf from Interdata - to use a sheave counter to meter off equal increments of probe travel, but to supplement this information with the use of an encoder on the winch drum in order to be able to measure total probe travel unambiguously. - to place all I10 device interfaces in a bin connected to the common controller. During this period considerable attention was dedicated to the design of the mechanical components contemplated it the original contract. Of these, only those required for vertical probe was complete at the time that it was decided to forego the mechanical subsystem and concentrate on developing the necessary electronics and software to interface with the probes being developed by the Bureau of Mines.

Jan 1, 2012

By Robert Stefanko

This report, rather than attempting to replace previous annual reports, supplements, and more importantly, coordinates and summarizes the entire effort. Even with such restrictions, the report is voluminous and, therefore, a decision has been made to divide it into two parts. The first volume is basically narrative and includes tabular results and analyses. The second volume is in appendix form giving detailed information. Together, they permit a logical discussion of all aspects of the project (Volume I) without cumbersome distractions but, at the same time, provide all the details to permit others to evaluate and explain the results or develop similar research programs (Volume II). The aim of the original proposal was basically to develop instruments and techniques and then make measurements of suitable power parameters, ground fault currents and ground resistance beds. With such information available, it was possible to develop a meaningful simulator which would permit investigating electrical systems and components on paper without costly trial and error procedures in the third year, a cable splice testing program was added to the project. While there were the usual delays attendant in such original research, these objectives were achieved.

Jan 1, 1973

By Jack Kadlecik

This final technical report describes the concept feasibility study, testing, design and development effort which went into. The quick opening enclosure access cover and flame path tolerance checking system. A detailed definition of the explosion-proof multiple start threads is shown for two (2) sized electrical enclosures.

Jan 1, 1972

By John E. Trombly

System objectives and design criteria for an in-mine ULF radio paging system are discussed Coding formats, frequency and bandwidth selection criteria leading to the system design are discussed. The prototype call alert transmitter and pocket page receiver is functionally described. The report includes circuit descriptions, schematics, parts lists, printed circuit fabrication and assembly drawings. The report concludes with an estimate of the manufacturing cost for each assembly.

Jan 1, 2011

By Andrew M. Leszcykowski

In 1984, personnel from the U.S. Bureau of Mines examined 41,550 acres of the North Fork Owyhee River Wilderness Study Area for mineral resources. This study area, in southwestern Idaho, is underlain by tuffs and basalt of Tertiary age. There are no known mines, claims, or prospects in or near the area. The northeast and southwest corners of the area are covered by oil and gas leases or lease applications, but no known exploration has been conducted. On Nickel Creek and Pleasant Valley Tables, in the southern part of the area, thin flows of vesicular, moss-covered basalt occur that are suitable for use as decorative building stone. The stone available for exploitation crops out over several square miles. However, more suitable material, outside the study area, is closer to potential markets.

Jan 1, 1986

By Jon G. Bredeson

The electromagnetic noise that exists in a mining environment is quite severe and was shown to have been reasonably well documented by a number of researchers in the Phase I Report. The noise levels are such that prudent communication design requires the careful use of all the electromagnetic noise data available. A comprehensive survey was undertaken to determine techniques used in various industrial environments to achieve secure communications in the presence of electromagnetic interference. The techniques were given in the Phase I Report and are rudimentary, but have produced reasonably good results. A number of these techniques could be applied to the mining environment.

Jan 1, 1980

By Philip E. Niebuhr

A procedure, which can be performed in the field by nonanalytical personnel, is given for sensitive spot tests for detecting tellurium or selenium. The expressed need of a field test for detecting small amounts of tellurium, which may be accompanied by relatively large amounts of selenium, has led to the development of this method. Tellurium search has been impeded by the lack of a satisfactory test from the standpoint of sensitivity and specificity. A quantitative laboratory method exists, but it is expensive and relatively laborious. Several other qualitative tests are known, but they require unstable solutions, which must be freshly prepared for use, and a greater variety of laboratory equipment. The particular advantages of the test described are its simplicity and the stability of the reagents required, there-fore is is well adapted for field use. Also, this test was found to be of practical use in the analytical laboratory when screening samples, thereby reducing analytical costs. The roughly quantitative interpretation of the results can save time by indicating the approximate size of the sample taken for a quantitative determination.

Jan 1, 1962

By R. R. Faddick

Properties of coal-water slurries were studied in two separate phases: a rheological phase and a pipeline phase. The purpose of the study was to investigate the rheology of fine coal slurries to determine the effect of fine particles in a coal-water mixture on the economic and operational aspects of a slurry pipeline. The slurries consisted of 6x10, 100x200, and 200x0 mesh coal in water. A fourth slurry consisted of a mixture of the 6x10 and 200x0 mesh coal. Brookfield and Stormer rotational viscometers were used to obtain or simulate rheograms for a range of fine coal concentrations, temperatures, and particle sizes. All the slurries were pumped through a 1-inch diameter acrylic pipe. The fine coal slurries were found to encompass four distinct rheological models. The narrow size distribution of the coal slurries was apparently responsible for the high pipewall friction losses, more so than the particle size. A scale-up method applicable to Bingham plastics was found satisfactory for predicting pipeline headlosses of fine coal slurries from rheology data.

Jan 1, 1974

By William R. Wessels

This report describes a field survey and laboratory investigation into the causes of failure of resiliently clad screen decks applied to coal preparation plants. Blinding of screen deck perforations and delamination of the resilient cladding are studied and mechanisms responsible for these failure modes are hypothesized. A laboratory test program to simulate the mechanisms was begun and abandoned when it became apparent that meaningful test results would require a substantially redirected effort. No meaningful test data was obtained from the laboratory simulation.

Jan 1, 1982

By Lloyd A. Morley

The problems associated with the presence of organic materials and of water in explosion-proof enclosures used in high voltage, high capacity applications were examined through a literature search and theoretical reasoning. Information on volatilities is presented. The conclusion is reached that explosive pressures are significantly enhanced by inclusion of these materials.

Jan 1, 1976

On April 1, 1982, the Bureau of Mines and the Department of Energy entered into an Interagency Agreement to develop an enhanced computer cost model for uranium in situ leach mining. The original computer cost model contained data base information related to two regions; the Wyoming basin region and the South Texas trend area. The enhanced cost model contains additional information on San Juan Basin type deposits. This addition is significant because it expands the model's capabilites to include one of the largest uranium producing areas in the United States and developes costs related to uranium production from in situ leach mining. The data base was expanded and modified to include changes necessary for San Juan basin type deposits. These changes included, but were not limited to, state and local taxes, royalty payments, depth of deposits, drilling costs, and electrical costs. Also site visits were taken to verify many of the base case parameters. Consequently, the data base has been incorporated into the computer program and existing software was modified to provide for the additional data. Information was obtained on drilling coats and therefore the current program more accurately reflects these costs to depths of 2500 feet. This depth parameter has been expanded to include Wyoming Basin and South Texas scenarios also. Verbal communications were held with one operator in the Crownpoint, New Mexico area as well as the state regulatory agencies to help validate the expanded model. As a result of these changes, several tables have been included, summarizing changes in the new default parameters and the overall range of input parameters.

Jan 1, 1982

By Irvin G. Burough

Andros Analyzers Incorporated has designed and built two prototype continuous methane monitors capable of being mounted on a mining machine'. These instruments were designed for in-mine safety use. The monitors incorporated an NDIR optical/electronic analyzer design in which the response to the sample gas (methane in air) was achieved by synchronous detection and measurement of the amplitude oscillations of the trasmitted energy from an infrared source caused by the pressure modulation of the sample gas within the optical cell. Zero and span stability were to be achieved by the amplitude modulating of the infra-red source and using detected signal to correct for optical/electronic system variation. This design effort was to simplify and reduce the cost of the major components while eliminating the need for daily calibration. This report is the final report on this effort.

Jan 1, 1981

By Wm. F. Netzeband

"The mode of ore occurrence and the methods and costs of mining at one of the zinc-lead mines in the Tri-State zinc and lead district, Oklahoma, are presented in this paper for the information of mine operators in other districts.No. 2 mine property was acquired by lease in 1918 after some 30 holes had been drilled and a shaft had been sunk to the 305-foot level by the first lessees. After acquisition of the lease, the present operating company drilled a rich ore body on the 260-foot level and in 1920 started sinking two shafts. Production was begun late in 1921, and the mine has been operated more or less continuously to the present time.The mill has a capacity of 400 tons in 10 hours, the usual length of the mill shift in the district.The geology of Mine No. 2 is very similar to that of Mine No. 13 except that the Cherokee shale is thicker, ranging from 80 to 160 feet, and all the formations are correspondingly deeper, the Short Creek oolite horizon here being at a depth of about 300 feet. The oolite has not been found on this property, but the lime comes in at about the level at which the oolite should appear.The ore deposits of Mine No. 2 occur in the brecciated and bowlder ground above the Short Creek oolite. The main or 260-foot level is about 40 feet above the oolite horizon, and the lower or 300-foot level is immediately above it.The ore deposition is controlled by a zone of shearing and fracturing, and the mineable areas are divided into two distinct runs which have a northwest trend with a lean or practically barren area dividing them. This characteristic has controlled the mining to a large extent, for it enables the mine superintendent to locate the large pillars in lean ore and leave only small pillars in the richer ore. Figure 1 shows the outlines of the ore body and the pillars.The ore on the main level occurs disseminated throughout the jasperoid breccia as patches or lenses in the jasperoid, or cementing massive bowlders of jasperoid breccia and chert. The ore of the lower level is more of the bowlder type than that on the main level and occurs chiefly cementing the bowlders but also with some disseminated ore in the jasperoid breccia.The gangue minerals are jasperoid breccia, chert, and dolomite. Calcite is found in minor quantities. Sphalerite is the principal ore mineral; galena is found only in minor quantities around the edges of the ore body. When galena is encountered in this ore body, the limit of the ore can be expected.The exploration and estimation of ore reserves at Mine No. 2 are similar in many respects to the methods used at Mine No. 1.4After the mine was opened up and the general character of the ore deposit had been determined, drilling operations were concentrated along the trend of the shear zone. Later drilling has proved what appears to be a parallel shear zone or an offset of the zone now being mined."

May 1, 1929

As a result of early experiments in underground mine illumination, the Bureau of Hines recognized the need for additional experience with the underground lighting of coal mines having low seam thicknesses. There was already experience with tile illumination of coal mines having higher coal seams, and this contract with Ocean Energy Inc. (OEI) was undertaken to contribute to the "low coal" experience. For the purpose of this contract, a "low coal? mine is defined as one having less than 45 inches of overall headroom in the working places. As a practical limit, 26 inches was the minimum coal seam thickness to be encountered in this program. In one instance, the maximum coal seam thickness was eight to ten feet, however, this particular work was at the direction of the Technical Project Officer (TPO) by virtue of the unique type of lighting arrangement that was to be evaluated which would be useful for low coal. At the outset of the contract, three major tasks were established. The first two tasks involved the installation of permissible fluorescent lighting equipment at two low coal mines. The intention was to illuminate mining sections in each case consisting of one or more machines. The third task was to illuminate a variety or mining equipment including a longwall. For the purpose of this report, the fol-owing identifies the particular installations associated with each task.

Jan 1, 1976

By David Hill

The Australian underground coal mining industry has made extensive use of the Coal Mine Roof Rating (CMRR) classification system for a diverse range of purposes in recent years. These include mining method selection, and coal pillar and roof support design. This paper outlines a series of case histories, from large-scale feasibility studies to local support design investigations, that collectively illustrate the broad applicability, advantages, and usefulness of the methodology, as well as some of the current limitations. The key role of the CMRR in an overall hazard definition methodology is demonstrated for a major Australian project, and some ideas with regard to the future application of the CMRR, in the context of geotechnical risk management within a progressive, highly productive extractive industry, are put forward.

Jan 5, 2007

By R. Karl Zipf, Kousick Biswas

The main objective of occupational health and safety research is to minimize or eliminate the events that may cause fatal or non-fatal injuries to human workers. A commonly used technique is to devise an “incident prevention plan”, which is more often the product of thorough investigations of past reported incident events. Incident documentation and methodical reporting and systematic and thorough data collection, often help identify the root cause of the incident – in other words, the etiology of the incident. These retrospective analyses of the incidents can efficiently identify the future steps to take to achieve the objective of minimizing occurrence of “events of interest”. This paper introduces a novel technique – “Taxonomic Analysis”, which identifies the root causes of an event (an incident in this case) and can provide future direction for corrective measures to reduce the probability of occurrence of the event. A taxonomic analysis involves systematic and organization of data based on observation, description, and classification. This paper utilizes the rock fall related incident narratives, available with the Mine Safety and Health Administration (MSHA) database (1984-1999), for a taxonomic analysis. The study found that 67.6% of groundfall incidents occurred in supported areas with the remainder (32.4%) in unsupported areas. Some form of rock mass failure appears to cause about 50% of groundfall incidents, although in 39.7% of the overall groundfall incidents or two-thirds of those involving rock mass failure, the exact nature of the rock mass failure could not be determined from the narratives. Human activities factors such as scaling or barring down, drilling or bolting, and setting timbers or cribbing accounted for another 34.5% of the groundfall incidents. Finally, support system failures made up the remaining 15.5%. Results from this taxonomic analysis may suggest focus areas toward which preventive measures and future research activities could concentrate.

By J. H. East

"INTRODUCTION Diesel locomotives have been used successfully in underground mines of Europe for 18 years, and much has been written on the technical details of the design of these machines and the safeguards provided by the manufacturers. The actual conditions under which' the Diesel locomotives are used have not been publicized as well and consequently are not well-known. In 1945 the writer observed numerous Diesel locomotives working underground in coal and metal mines of several European countries and was favorably impressed with the practical approach to the safe use of this- type of equipment.Recent statistics showing the number of Diesel locomotives in use are not available now because of the World War, but the extent to which this type of mine locomotive was used immediately before the war is indicated by table 1, which classifies the number of locomotives used in several countries according to the type of power, such as compressed air, Diesel, and electric.Mining conditions observed by the writer in the European countries are very different from those in most coal-mining districts of the United States. The surface plants are larger and are permanently constructed of brick or concrete; numerous coal beds are worked through one shaft; the crosscut rock tunnels or levels, driven to intersect the coal beds, are lined with brick or concrete blocks where needed instead of timber; the coal beds dip more steeply and are not as thick as in most fields of the United States."

Sep 1, 1946