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By W. P. Yant, G. W. Jones

"Introduction.During the past two years the Bureau of Mines has conducted a study of natural-gas heaters*** to determine (1) what types of heaters literate carbon monoxide; (2) why carton monocide is liberated; and (3) how, by change of design or construction, the liberation of this gas can be largely eliminated, In addition to the above study the bureau has investigated cases in the Pittsburgh dis¬trict where fatalities have resulted from carbon monoxide given off by natural-gas heaters.Since these fatalities were first brought to the attention of this bureau through the press, it is likely that some cases were missed and thus not listed. On the other hand, some cases reported as being due to carbon monoxide poisoning, on investigation were found to be due to causes other than carbon monoride.The cases listed herein were shown in all probability to be due to carbon monoxide. Those in which there is any doubt have been omitted; so have those in which there was part asphyxiation, where the victims later recovered."

Feb 1, 1924

By Virgil Miller

Bureau of Mines Reports of Investigations 3244, 3245, 3246 and 3264 give data of detailed studies on smelting in the lead blast furnace handling zinciferous charges at Trail, B. C. The present paper gives more on analyses of the gases leaving the top of the charge and on accretions formed on the walls of the blast furnace. New data are presented to show the effect of the temperatures at the tuyere zone on the lead content of the slags made. The greater part of this paper, however, deals with a much debated subject, namely air used in lead blast furnaces. Original data are presented to show the effects on smelting lead 'products when air is supplied to a lead blast furnace under volume versus under pressure control.

Jan 1, 1940

By Virgil Miller

Bureau of Mines Reports of Investigations 3244, 3245, 3246 and 3264 give data of detailed studies on smelting in the lead "blast furnace handling zinciferous charges at Trail, B. C. The present paper gives more on analyses of the gases leaving the top of the charge and on accretions formed on the walls of the blast furnace. New data are presented to show the effect of the temperatures at the tuyere zone on the lead content of the slags made. The greater part of this paper, however, deals with a much debated subject, namely air used in lead blast furnaces. Original data are presented to show the effects on smelting lead 'products when air is supplied to a lead blast furnace under volume versus under pressure control.

Jan 1, 1940

The compliance sampling method for coal mine dust in the United States has not changed appreciably in the last 30 years. A call for more frequent sampling with immediately available results is leading to new instruments that may supplement or replace the existing sampler. This report discusses two such instruments that provide immediate results of dust levels. The first, called the Respirable Dust Dosimeter (RDD), is designed to supplement the existing U. S. cyclone compliance sampling method. It uses the pressure drop across a filter to provide an inexpensive screening type of measurement. The RDD has been tested in the laboratory and a limited number of coal mines. Side by side testing has compared the RDD performance with personal coal mine samplers in triplicate area sample measurements. Results show that the differential pressure of specific filtration media can be an effective surrogate for respirable mass. Data show that there is a dependence on coal type and an effect of relative humidity. There also appear to be two distinct responses related to coal type. For specific coals the coefficients of determination, R2, are better than 0.9. For general use the detector tube, using laboratory generated calibration curves, can be used to estimate respirable dust levels. However, a calibration to a specific coal type may substantially improve the accuracy. Another sampler in development is called the Personal Dust Monitor (PDM). Designed to give compliance quality accuracy, the PDM uses the frequency change of a vibrating element to measure dust and give immediate feedback of results. Results of laboratory comparison of the prototype PDM sampler to personal gravimetric samplers indicate R2 values of better than 0.99 for three different coal types. Work is in progress to package the components into a person-wearable unit combined with a cap lamp system with a total projected weight of less than 1.4 kg (3 lbs).

By Sean Gallagher

Humankind's interest in measurement of human physical strength probably dates to the first humans. At that time, life was truly a struggle in which the fittest survived. To a great extent, fittest meant strongest. Interestingly, current interest in human physical strength in the workplace stems from 1970-1980s vintage research demonstrating that persons with adequate physical strength are less likely to be injured on physically demanding jobs. Survival in many modem workplaces may still be a case of survival of the strongest. There is, however, a flip side to this issue - that persons with limited strength are more likely to be injured on "hard" jobs. To address this problem, we can apply what we know about physical strength to job design. "Hard" jobs can be redesigned to be within the physical strength capability of most people. Since physical strength is important to these jobs, we must find ways to quantify it through testing. This publication concerns human physical strength testing. Its purpose is not to recommend any particular type of testing, but rather to describe the types of testing available and their uses. It is up to each individual user of strength testing to decide which testing technique is most appropriate for his or her particular application. This booklet discusses four types of strength testing: isometric, isoinertial, psychophysical, and isokinetic.

Jan 1, 1998

By Mark S. Sanders

The present study was designed to explore the contribution of organizational climate and management practices to the injury experience in underground coal mines. A cross-lagged panel design was used in which miners from 22 mines completed questionnaires assessing 27 organizational climate, structure, and function dimensions on two occasions, The results strongly support the hypothesis that climate and management practice have casual effect on the incidence of disabling injuries.

Jan 1, 1976

By Bradley V. Johnson

This publication summarizes the in-house and contract research and development projects conducted since 1974 by the Bureau of Mines for the control of noise and vibrations from surface mine blasting.

Jan 1, 1982

By Kenneth C. Stewart

The overall purpose of this study was to develop and evaluate, in the laboratory, instrumentation and procedures which might allow for the use of physical measurements of earmuff attenuation which would yield results equivalent to those obtained from psychophysical measures of attenuation. The ultimate goal was to evaluate techniques which might subsequently prove feasible for physical measurement of earmuff attenuation in the field. Current instruments were modified to have a response similar to differrences observed in earmuff attenuation as observed in Volume 1 of the current contract. Mining noise spectra were selected and presented to a single subject seated in a diffuse noise field. The subject wore one of the muffs evaluated in the earlier study and was also fitted with two physical sound measurement systems. A linear system measured the "outside" noise level and a linear system plus "correction" filter measured the "in-side" noise level. These measurements indicated that, under the procedures presented in this report, a laboratory method for measuring earmuff attenuation is feasible and yields results comparable to an extensive psycho-physical procedure.

Jan 1, 1980

By John C. Machisak

STATISTICAL data on injuries and employment pertinent to metal mines and to their mills, and/or processing plants are presented in this Information Circular for the calendar year 1960. The information pertains to metal mines, as well as ore-dressing plants and primary nonferrous smelters, refineries and reduction plants, and their auxiliary works. These data are voluntarily submitted annually to the Bureau of Mines by the operators, and contribute greatly toward the promotion of safety in the mineral industries. The data presented are classified according to the principal mineral produced and include information on copper, iron, lead-zinc, gold-silver lode, gold placer, uranium-vanadium and miscellaneous metals. A breakdown of miscellaneous metals by commodities is shown in table 19, page 41. The data also relate to workers engaged in production, exploration, development, construction, and maintenance and repair work, as well as supervisory personnel and office-workers at the mine or plant site. Injury and employment data at metal mines and metallurgical plants in the United States for 1960 are shown under the following general sections: 1. General injury experience: Tables I-5-Data on injuries, injury-frequency and severity rates and related employment data, work location, and degree of injury.

Jan 1, 1963

The following Inventory was prepared to provide mineral deposit data to the U.S. Army Corps of Engineers for use in the Resource Development Navigation Study in Alaska. The inventory was prepared using data contained in the U.S. Bureau of Mines Minerals Availability System (MAS) database. The Alaska portion of the database contains Information on over 7,000 mineral locations and deposits throughout the state. When MAS was established In 1975, database entries were originally compiled from literature searches by both Bureau personnel and contractors. Deposit data are obtained/maintained through Information gained from a variety of sources, Including published and unpublished Bureau of Mines reports, records, and files; U.S. Geological Survey (USGS) Bulletins, Professional Papers, and other reports; technical and professional Journals; State and other Federal agency publications; data generated during field examinations; and information obtained from knowledgeable individuals. Because of the size of the data base, many of the data have not been significantly modified since initial entry. Each deposit on the MAS data base has a sequence number of the following form:

Jan 1, 2011

By M. G. Zabetakis, T. D. Moore

The use of a partially slotted 6.5-inch-inside-diameter vertical pipe to remove methane from a longwall gob area at a depth of 2,260 feet in the Pocahontas No. 3 coalbed ms investigated. The value of gas removed by such a pipe under free-flow conditions was found to equal the cost of the installation in this case. Approximately 25 percent of the available methane passed through the pipe without the use of an exhauster; an additional 10 percent was removed when an exhauster was employed. The diversion of methane through a vertical slotted pipe to the surface permitted the use of increased mining rates and decreased the ventilation air requirements.

Jan 1, 1972

By M. P. Board, J. K. Whyatt, T. J. Williams

The U.S. Bureau of Mines has been conducting a series of rock mechanics investigations at the Lucky Friday Mime in the Coeur d'Alene Mining District of northern Idaho. In the present study, the energy release rate (ERR) index was used to evaluate three underhand stope backfill parameters--cement content, density, and placement gap-to determine their influence on rock bursts. This index provides a relative measure of the likelihood of rock bursting for a given rock mass. It is known that the elastic idealization of the rock mass inherent in this method causes underestimation of stope closure and hence underestimation of the influence of backfill on rock bursting. However, this evaluation still showed that (1) changing from present practice to one in which backfill was omitted altogether would increase the ERR by 42 pct and (2) perfect placement of backfill would reduce the ERR below present practice levels by 28 pct. The easiest step toward perfect placement would be elimination of the placement gap, which accounted for half of the difference in ERR between present practice and ideal placement conditions. There was no indication that increasing initial fill strength through increased cement content would affect the ERR.

Jan 1, 1992

By S. Harteis, D. Dolinar

Many mining operations rely on bulkheads to provide a barrier between impounded water or slurry and active mine workings. However, bulkhead failures could cause and have caused catastrophic flooding that puts the underground workforce at risk. The National Institute for Occupational Safety and Health1 (NIOSH) in collaboration with the Mine Safety and Health Administration (MSHA) is conducting research to evaluate the adequacy of existing design practices for water and slurry bulkheads. A key component of this research effort is documentation of the performance history and design parameters for bulkheads installed in underground coal mines during the last 20+ years. This research is part of a larger effort to develop general design guidelines and procedures for constructing and maintaining bulkheads that will help to ensure their long-term structural integrity, while significantly reducing the inundation risk for miners. This paper presents the results of NIOSH’s research to identify state-of-the-art bulkhead designs, including design criteria, leakage monitoring systems, and emergency warning systems. Underground observations and evaluations of existing bulkheads suggest that the most important design factors influencing their performance are the interface of the bulkhead with the surrounding strata and the potential magnitude of the hydraulic pressure to which they may be subjected. When a bulkhead has failed, leakage has generally been through the surrounding strata or along the bulkhead/strata interface, with the failure potential along the interface increasing with hydraulic head. It was also determined that development of a monitoring program to ensure the long term structural integrity of bulkheads is an important safety consideration. Current monitoring procedures range from weekly visual inspections to constant monitoring via pressure transducers and fluid level indicators. Where possible, these devices are used in conjunction with a computer based mine monitoring system to alert mine personnel when an emergency condition exists at the bulkhead installation.

By Elaine T. Cullen

Human beings are natural storytellers and story listeners. We learn very early that stories entertain us, but also give us the ?rules? about what is expected of us and how to make meaning of our experiences. Stories are integral to our lives, and have great power to change or influence how we think or how we react. They are an innate part of how we learn, and have obvious benefits to trainers or educators who are trying to impact what and how we learn. This paper and presentation discuss the social and cultural power of stories, and how they have been used to develop training for skilled blue-collar workers. Included will be examples as well as suggestions for trainers on where to find stories, what type of stories to pay attention to, and how to use them to improve occupational safety training.

Jan 1, 2008

By Charles M. Keenan

THIS PUELICATION lists and provides brief accounts of the major disasters not classified as explosions of gas or dust that have occurred in the cod mines of the United States from the earliest times to the present. Together with an earlier publication of the Bureau2 it provides information on all the known major coal-he disasters (disasters causing five or more deaths) in this Nation's history. Sources of each account are given individually. In each account the actual words of the original publication are used unchanged, but sentences or paragraphs referring to details that are not significant have been omitted. In those few cases where conflicting data were reported in different publications the selected version is the one that appears most logical and which in general is in agreement with most of the other accounts.

Jan 1, 1963

By John C. Machisak

STATISTICAL data on injuries and employment pertinent to metal mines and to their mills, and/or processing plants are presented in this Information Circular for the calendar year 1960. The information pertains to metal mines, as well as ore-dressing plants and primary nonferrous smelters, refineries and reduction plants, and their auxiliary works. These data are voluntarily submitted annually to the Bureau of Mines by the operators, and contribute greatly toward the promotion of safety in the mineral industries. The data presented are classified according to the principal mineral produced and include information on copper, iron, lead-zinc, gold-silver lode, gold placer, uranium-vanadium and miscellaneous metals. A breakdown of miscellaneous metals by commodities is shown in table 19, page 41. The data also relate to workers engaged in production, exploration, development, construction, and maintenance and repair work, as well as supervisory personnel and office- workers at the mine or plant site. Injury and employment data at metal mines and metallurgical plants in the United States for 1960 are shown under the following general sections:

Jan 1, 1963

The NIOSH suite of coal mine ground control software addresses nearly every aspect of coal mine ground control planning, including geologic characterization, mine layout, pillar design, and support selection. Mine planners who use the soft-ware have access to the knowledge gained during years of NIOSH research—packaged in a simple, easy-to-use format. Several of these software packages have recently been updated and improved. Analysis of Roof Bolt Systems (ARBS) (Figure 1) helps select the proper roof bolt system design from the immense variety of available bolt types and patterns. It was developed from statistical analysis of extensive bolt performance and roof fall data. New features in Version 2 include— • The capability to analyze roof bolt systems that use two types of bolts; and • A roof support cost module that estimates the total in-stalled cost of different patterns, considering the costs of consumables, labor, maintenance, and other factors. The Support Technology Optimization Program (STOP) (Figure 2) can be used to make judgments regarding which secondary support system will be the most effective in a particular mine condition and to evaluate the advantages or dis-advantages of alternative support systems. Version 3.0 includes additional improvements: • Supports with large load-shedding following yielding can be designed based on the peak loading capability as well as the residual loading capability; • Seven new support systems have been added to the program; and • Easier access to photo gallery has been provided. The Coal Mine Roof Rating (CMRR) replaces com-plicated geologic information with a simple numerical rating that mine planners can use in many ground control applications. The CMRR can be readily integrated into a geologic exploration program, and the software package is capable of generating an AutoCAD CMRR "layer." Version 1.2 contains— • The complete CMRR database with more than 250 ratings obtained from 70 different U.S. coal seams; and • An all-new "Help" file that clearly explains all aspects of the program. Analysis of Horizontal Stress in Mining (AHSM) can help find the optimum mine layouts for control of horizontal stress. It can be used to analyze both development and longwall retreat designs, and it shows how the stress condition varies as the entry, crosscut, and panel orientations are changed. Version 2 features— • Improved graphics that enable the user to observe the effect of design changes without adjusting the display on the computer screen; and • Resource files containing information on stress map-ping, advance-and-relieve mining, stress measurements in U.S. coal mines, and other topics. [ ]

Jan 4, 2006

By H. A. Dierks

Implementation of the joint Federal-State control program established in 1955 to cope with the mine water problem in the Pennsylvania anthracite region is described in this report. The increasing severity of the water problem in the anthracite mines has necessitated major adjustments as this continuing program has progressed. Since 1941 the Federal Government has recognized the mine water problem as an important factor in the worsening economic condition of the anthracite region by initiating scientific and technologic investigations and establishing the Anthracite Flood-Prevention Section in the Bureau of Mines in 1948. On the basis of comprehensive investigations and studies, the results of which were published in numerous reports and bulletins, the Anthracite Mine Drainage Commission of the Commonwealth of Pennsylvania formulated a plan that served as a background for legislative action in 1955, resulting in Public Law 162, 84th Congress (Act of July 15, 1955 (69 Stat. 352; 30 U.S.C. 571-576)), for the Federal Government, and Act No. 82 of the General Assembly, July 7, 1955, for the Commonwealth of Pennsylvania. The report covers 29 mine flood control projects approved and executed in implementing the aforementioned legislative acts. Essential engineering and cost details for each project are given, together with an evaluation of the effect that the installed facilities have on alleviating the mine water problem as it concerns individual mines and the anthracite industry as a whole.

Jan 1, 1962

By John R. McWilliams

This report is one of a series published by the Bureau of Mines describing methods and practices at various mines throughout the United States. A previous program, conducted from 1928 to 1939, was well received by the mining industry and technical institutions and provided much source material for engineering textbooks and technical handbooks. The stringent wartime demands on the mining industry, the rapidly changing postwar economic situation, and greatly accelerated technologic growth have combined to render many of the previous data obsolete. The objective of the present program is to assemble reliable technical information on mining methods and practices throughout the country and present it for the use of the mining industry, technical schools, textbook authors, and other interested persons. This report deals with the design and development of the Berkeley open- pit mine at Butte, Mont., owned and operated by The Anaconda Company. The Berkeley pit is but one facet of a well-organized and integrated copper-mining operation involving the entire Butte district. Vein-type mining, important for 75 years, is still in progress at depths from 600 feet to nearly 1 mile; on intermediate levels, low-grade ore left untouched by earlier vein-type mines is being extracted by block caving entire ore zones,3/ and secondarily enriched but lower grade near-surface portions of the same ore zones are being mined by open-pit operations (fig. 1). The Berkeley pit itself is named for the Berkeley mine, one of the old mines that extracted copper ore from high-grade veins in the area that now will be mined by open-pit methods.

Jan 1, 1959

By Alexander Siefert, Steffen Pankoke

In the development of commercial vehicles as well as of passenger cars, the effects of vehicle vibrations on operating safety, health and comfort can only be predicted by numerical simulation when appropriate occupant models are available. Such models must be based on human anatomy and have dynamic properties of real humans in order to achieve realistic results. Since human dynamic behavior depend on posture and percentile, the occupant model needs to be adjustable to these parameters with respect to geometry and dynamic properties [1,2]. Dynamic Human Finite-Element-Model CASIMIR CASIMIR is a non-linear, dynamic finite-element-model of the human body. It consists of a dynamic model of the upper torso with head, neck, shoulders and arms as well as of a dynamic model of the lower extremity with pelvis and legs. The most important part is the lumbar area with dynamic non-linear models of the lumbar spine and of back and abdominal musculature. The frequency-dependent characteristics of the intervertebral discs and the effects of muscle activation and non-linear frequency-dependent muscle properties are included. In the latest stage of development, CASIMIR has been equipped with a compliant model of the body surface in the contact areas to the seat. This results in a very realistic transmission of static and vibrational forces into the human body, see fig. 1. Intense model verification and validation has been performed in all stages of model development, starting with validation of small components like intervertebral disc, ending with validation of whole-body-vibrations using measurements of the dynamic mass / mechanical impedance [4]. For an in-detail examination of stresses in the vertebral bodies and discs, a non-linear submodel of the lumbar spine with an increased number of degrees of freedom can be coupled to the whole-body-model, enabling the researcher to examine local effects of vibrations and single shocks on the lumbar materials. [ ] Since it is well known that human dynamic behavior is significantly affected by anthropometric data and posture, CASIMIR can be individualized to the anthropometric status of single individuals or to the mean values for specific percentile groups. Furthermore, posture can be adjusted to the seating conditions applicable to a specific vehicle. Posture modification capabilities include the variation of the lumbar lordosis [3].

Jan 6, 2006