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By James Westfield

A brief resume follows of some recent activities of the Division of Coal-Mine Inspection that have had a favorable effect on health, safety, and the reduction of injuries at coal mines: 1. The Federal Mine Safety Code for Bituminous-Coal and Lignite Mines of the United States was issued originally by the Director of the Bureau of Mines on July 24, 1946, after consultation with management and labor representatives of the coal-mining industry. The code has been used by Federal coal-mine inspectors during their inspections of bituminous-coal and lignite mines as a basis for determining the existence of unhealthful and unsafe conditions and practices in these mines. A revised code was issued by the Secretary of the Interior October 8, 1953, following further consultations with representatives of management and mine workers, and was incorporated by reference in the 1952 and subsequent bituminous-coal wage agreements. The agreement of May 29, 1946, between the Secretary of the Interior, acting as Coal Mines Administrator under authority of Executive Order 9728, and the United Mine Workers of America, covering bituminous-coal and lignite mines in Government possession, charged Federal coal-mine inspectors with the responsibility of making periodic investigations of the mines and reporting to the Coal Mines Administrator any violations of the Federal Mine Safety Code. The inspectors were active in making prompt investigations of hazardous mines that had been closed by order of the Coal Mines Administrator to determine if enough improvements had been made to allow the mines to reopen. Federal coal-mine inspectors also had temporary authority to close mines they found to be imminently dangerous, but such authority (under Executive Order 9728) was removed on June 30, 1947, when Government control of the mines was terminated.

Jan 1, 1957

By Joseph L. Buckley

A total of 55 conveyor belt fire tests were conducted in the Bureau of Mines Fire Test Gallery, located at the Factory Mutual (FM) Fire Test Center West Glocester, R.I. The objectives of these tests were to: 1) determine the fire resistance and burning characteristics of various conveyor belt materials under simulated mine conditions; 2) provide essential data for designing a reliable bench-scale conveyor belt fire resistance test; and, 3) determine fire test conditions that will discriminate between low, moderate and high fire resistant materials. Belts, representative of those which mold he found in underground coal mines were examined under n umber of experimental conditions which included; ignition intensity; air flow rate; ratio of belt bright (h2) to overall gallery height (h1); exposure time; and, belt width. It was found that fire propagation could be achieved for some "fire resistant" belts (complying with the present Schedule 2G standard for approval) when exposed to an Ignition source of =6000 Btu/min for a 15-min period at a belt height ratio of 01.66. There appears to be a dependency of flame propagation on air flow rates and belt width, although the tests performed do not provide a quantitative trend. Recommendations are made for additional work to resolve some anomalous date and to fill voids in the rest program.

Jan 1, 1978

By C. F. Jackson

This paper has been prepared as a progress report in connection with the series of articles on mining methods and costs which are being published by the U. S. Bureau of Mines in the form of information circulars. When enough circulars have boon completed it is planned to publish a more complete and comprehensive paper in bulletin form dealing with the subject of underground transportation. Progress reports, followed b., bulletins, will be prepared from time to time dealing with other subjects included in the general study of mining methods at individual nines, such as mine development, drilling, and blasting; stoping methods (each principal stoping method to be summarized in a separate paper); Ventilation; wage, contract and bonus systems, etc.

Jan 1, 1931

By R. L. Rock

The Bureau of Mines conducted radiation-ventilation studies in six large underground uranium mines to investigate the extent of radon-daughter exposure experienced by the miners and to analyze the ventilation systems to set what changes were required to achieve recommended radiation standards. The studies entailed tracing and measuring the mines' ventilating air, quantitatively and qualitaitively, from its entrance into the mines, through production areas, and lack to the surface. Pressures consumed in creating airflow through mine circuits were determined by altimeter surveys. Air quantities were measured with anemometers or by chemical smoke cloud methods. Air quantities delivered through tubing were determined using U-tube water gages to magnahelic gages to measure velocity pressures. Radon-daughters were filtered from mine air to measure alpha activity; activity levels were converted to "working levels," the established unit for reporting miner exposure. Attention was given to locating unnecessary contamination influx sources and recirculating air. The radiation-ventilation surveys showed that where basic principles of food ventilation were not followed, high alpha radiation levels invariably resulted. Some mines required more primary air for controlling radiation levels throughout active areas, but more efficient use of available air was generally possible. Premature contamination of intake air was prevalent where development Openings intersected ore or passed by worked-out stopes. Several auxiliary systems were inefficient in secondary distribution, recirculating air already too highly contaminated for ventilation. Many got these common problems can be traced try the lack of dine planning with radiation control in mind.

Jan 1, 1969

By Lester J. Crow

This study advances the use of elemental sulfur in structural materials by demonstrating its value in bonding high-strength, well-graded basalt aggregates to form sulfur-basalt concretes. Sulfur is an excellent bonding agent, and the strength of a thermoplastic sulfur-aggregate mixture depends, to a large degree, on the strength and grain-size distribution of the aggregate used. A 3-cubic-foot, electrically powered mixer with heat applied to the barrel was used to mix the sulfur and aggregate. Sulfur content of several mixtures was varied to obtain the best workability with a minimum of sulfur in excess of that necessary to fill the voids. The average grain sizes and grain-size distributions were also varied to determine their effects on strength. Unconfined compression tests of forty-five 6-by l2-inch cylinders yielded average strendths of 3,348 psi to 10,398 psi. The highest strength single cylinder was 10,717 psi. The cylinders were tested from 24 hours to 6 days after pouring; after 24 hours the rise in strength was very slight. From the results obtained it appears that sulfur can be a useful construction material. An evaluation was made of a high-vacuum application for sulfur concrete. Sulfur has a high vapor pressure at elevated temperatures, 50° to 100° C; consequently, significant losses by sublimation can be expected. At lower temperatures the losses are not significant; however, this factor will limit its use at a higher temperature.

Jan 1, 1970

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 F. E. Walker

The Bureau of Mines determined total sulfur and sulfur forms for coal in 283 counties in 29 States and 2 fields of the State of Alaska. Specifically, organic, pyritic, and sulfate sulfur were measured of approximately 2,900 samples, and they include most of the coalbeds in the United States.

Jan 1, 1966

By F. E. Walker

The Bureau of Mines determined total sulfur and sulfur forms for coal in 283 counties in 29 States and 2 fields of the State of Alaska. Specifically, organic, pyritic, and sulfate sulfur were measured of approximately 2,900 samples, and they include most of the coalbeds in the United States.

Jan 1, 1966

By O. P. Hood, G. St. J. Perott, S. P. Kinney

"FOREWORD (By O. P. Hood, Chief mechanical engineer).During the war certain suggestions concerning power production were made by Mr. Walter E. Trent to the War Inventions Board, and at the request of the War Department facilities for experimental work were provided on the grounds of the. Bureau of Standards.The experiments were along the line of controlling the conditions of combustion in a closed space. In order to reduce slag troubles, experiments were carried out for removing ash from powdered coal. After the war, work along this line was continued, resulting in the Trent Process, which agitates or beats together powdered coal, water and oil.A new technology had previously been given to ore preparation by the use of small quantities of oil in water with froth flotation, and although the methods, results and mixtures of the Trent Process were quite different, yet the same physical phenomena of differential wetting used, and the possibility of there being interesting results in fuel technologic was evident. A cooperative agreement was entered into, whereby the Bureau of Mines was to investigate the underlying physical and chemical facts and make them public, and the Trent Corporation was to pay the cost of the investigation.The several reports as made have been available to any one interested, and are now to be published. While the Bureau of Mines felt justified in investigating the physical phenomena so far as might be done in a laboratory, and so far as public interest might reach, no attempt was made to discover the commercial possibilities which development might bring. The question of commercial possibilities must be left for commercial enterprise to answer."

Jul 1, 1921

By James J. Dowd

During and immediately following World War II, the heavy demands for steel required the mining of unusually large quantities of coal for the manufacture of metallurgical coke. The largest demand for metallurgical coke is in the Appalachian region, which comprises central and western Pennsylvania, Maryland, West Virginia, Virginia, eastern Kentucky, Tennessee, and Alabama. This demand is satisfied by coke made from coals within the region; consequently, the reserves of coking coal in this region are being depleted more rapidly than reserves in other coal-producing regions. The supply A' high-quality coking coal during the war was inadequate, and some coke were forced to use inferior coals. The coke produced from these inferior coals adversely affected the rate of production. Another national emergency probably would produce a similar condition, and in the interest of -national security, the Munitions Board of the National Military Establishment requested the Bureau of Mines to evaluate the reserves of coals suitable for the manufacture of metallurgical coke. All bituminous coals in the Appalachian region are coking, and as the coal that produces the better metallurgical coke become depleted, other coal previously considered inferior will be used. The general trend is toward the use of lower-quality coals for metallurgical purposes.

Jan 1, 1950

By Lucia Kuizon

The Pinnacles Wilderness Contiguous Wilderness Study Area (WSA) (CA-040-303) is 30 miles south of Hollister, CA, in San Benito and Monterey Counties. It is composed of five parcels of public land totaling 5,838 acres adjacent to the Pinnacles National Monument. The U.S. Bureau of Land Management later reduced the size of the Recommended Suitable Area (RSA) to 2,200 acres. U.S: Bureau of Mines personnel examined the entire WSA in May 1984. The WSA is underlain by Tertiary sedimentary and Cretaceous plutonic rocks. Diatoms occur in interbedded tuff, shale, and sandstones in the northern part of the WSA, but outside the RSA. In 1984, there were no mines, prospects, mining claims, leases, or mineral resources in or within one mile of the study area. No energy minerals were identified; however, an oil well was drilled in 1951 in the northern part of the WSA, but outside the RSA; it was a dry hole.

Jan 1, 1985

By John R. Coulson

Each State and the Federal Government was surveyed for existing certification requirements, the industry yes surveyed for the needs for training blasters, and the training that was available. Recommendations for training and certification for blasters were made.

Jan 1, 1980

By J. C. Fowler

[This i.untra t hds bmii III c'IIILt fur till- past 1':?:u yrlr;, Till-- wurir pnrfor rw:it '. ,JS hlui.rn dawn Ilttf lit Iu i eel i ih?IS( S. 1 hesrt aIII, Phase I Candor tlri I a lest It) donurnSlrale SeiSrrlir nurihudS to hu USi!d lot ttlr? rti?tei thin and Iu" ainnl ul trapped rrlinc:rs hitting (-)it the roof with a harnrner, Phase I' Design and cunStrur.t a permanent Seismic monitor System to rrlunrtur roof (ails arm r:xploslun', III ,r 'Vol king mine. Phase III - Ire dII an an i i irr for sVstl rtl Ii i`'Smltur air quality in till, niitii iiH II ? ir,iti tin; niln !III ;I I ,, i; Phase I V - Conduct 11(21 d tests of the seismic IT IUnit UT ieq system fur a period nl two 11IUIIIIIS. Phase, V - Condirct three test periods of the seismic system over a period of six mimilis. Detailed reports covering the wurk. done in Phases I, 11, and IV have been i : . r tr I - i t report will, therefore, cuni.entrate on the work perfurmed in Phases III anti V.]

Jan 1, 1975

By Harry Vivian

This paper deals principally with the retreating method of mining as applied in the Calumet & Hecla Consolidated Copper Co.'s deep Conglomerate mine, pointing cut some of the difficulties encountered in deep mining and describing the particular methods used at Calumet to carry on a large-scale operation at great depth with a minimum hazard factor. The circular is one of a series dealing with mining methods and costs which is being prepared for and published by the United States Bureau of Mines. ACKNOWLEDGMENTS Acknowledgment is due to those officials and operating heads of the Calumet & Hecla Cc. whose years of familiarity with the conditions developing at the Conglomerate mine as great depth was attained have enabled them to contribute valuable information to the subject of deep-mining problems.

Jan 1, 1931

By M. L. Fenger

This report describes a study of the factors which affect medium voltage (661 - 1000 volts) and high voltage (1001 - 7500 volts) trailing cable couplers for use in underground coal mines to connect trailing rabies. Improvements in quality, dependability, and safety of medium and high voltage couplers are presented in the form of requirements for couplers. The results of an investigation of high voltage trailing cable coupler design and of whether trailing cable couplers must have a metallic shell as required by CFR 30 part 75.805 are presented. Conclusions and recommended research programs are included that describe the present situation and future development approaches.

Jan 1, 1978

By C. H. Herty

As the problem of inclusions in steel has become increasingly important, more and more attention has been paid to the source of the oxide inclusions in steel. In killed steels the oxide inclusions are traceable to the reaction of deoxidizers with the iron oxide dissolved in the steel during the refining period of the open-hearth heat. In a large class of steel known as "rimming steel" the action of the steel during solidification depends entirely on the gas evolved, and this evolution in turn is controlled by the amount of iron oxide in the liquid steel in the mold. It is therefore of great importance to be able to determine the amount of iron oxide dissolved in steel and to devise methods for the control of iron oxide in any class of steel. The object of the present investigation was to obtain a true value of the oxygen content of liquid steel. If the steel has not been deoxidized, the greater percentage of the oxygen is present as iron oxide in solution.

Jan 1, 1932

On September 4, 2007, Mine Safety and Health Administration, in alliance with the International Union of Operating Engineers and the International Association of Bridge, Structural, Ornamental, and Reinforcing Iron Workers, presented the first annual Mine Construction Maintenance and Repair?s Safety Contractor of the Year Award to Artisan Contracting, Inc., of Cape Girardeau, MO. Eligible contractors located throughout the United States were nominated. Artisan Contracting was nominated by Illinois Cement Company located in LaSalle, IL. Illinois Cement Company is a Division of Eagle Materials Inc., located in Dallas, Texas. Mr. Larry Frankum President of Artisan Contracting Inc., stated, ?While it is gratifying to receive a wonderful award such as this, we must not forget how fragile a good safety record is. We must constantly remain diligent in pursuit of maintaining safe work sites.?

Feb 1, 2008

By Linneas W. Laage

MFIRE is a computer simulation program that performs normal ventilation network planning calculations, and dynamic transient state simulation of ventilation networks under a variety of conditions. The program is useful for the analysis of ventilation networks under thermal and mechanical influence. MFIRE simulates a mine's ventilation system and its response to altered ventilation parameters, external influences such as temperatures, and internal influences such as fires. Extensive output enables detailed quantitative analysis of the effects of the proposed alteration to the ventilation system Network simulation using digital computers has become widespread throughout the mining industry in recent years. However, as the sophistication of the simulator increases (MFIRE, for example), the complexity of input data requirements and interpretations of results requires more skill and knowledge from the users. Perhaps the most difficult part of using MFIRE is to construct the data set describing the mine's physical layout and its ventilation properties. The initial attempts to get the data set running often reveal unknown or ignored aspects of the mine's ventilation.

Jan 1, 1995

By T. A. Klinefelter

ONE OF THE many services rendered by the Federal Bureau of Mines is the identification and general examination of ore and mineral samples. Many of these, coming from almost every State in the Union, are clay and shale samples. Other Government agencies, State geologists, universities, and other laboratories are often requested to make similar examinations. This publication describes methods of testing these samples. An earlier paper, published in 1943, described Bureau of Mines methods of testing such clays.3 This paper was to be followed later with another (part II) that would describe much more thorough testing than did the rather general outline of part I. Part I has been out of print for some time and needs revision, and part II was never written; hence, the present publication is designed to include part I and also those additions intended as part II. The tests presented in part I were simple, requiring only the ordinary equipment to be found in any good chemical laboratory. The second publication was to include a greater number of test procedures and information on increasing the accuracy and precision of those previously given.

Jan 1, 1957

By Gerald P. Scanlan

Control of the dust produced by continuous mining machines in coal mines is generally obtained by water sprays from fixed nozzles mounted on the frame of the machine in back of the cutting head. Mounting the nozzles on the rotating head of the machine closer to the coal cutting bits may improve the efficiency of dust suppression. To test this concept, respirable dust measurements were made during 39 regular production shifts in an underground mine using a Joy 11CM continuous miner. The equipment used, difficulties encountered, and measurements obtained are described.

Jan 1, 1974