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By R. Michael Digman

Few efforts have been undertaken to date to assess the quality of mandated coal mine health and safety training for new miners and for experienced miners. This study was concerned with the quality and effectiveness of existing classroom health and safety training programs. The study involved field data collection through pre- and posttesting of trainees, audio-taping class sessions, and administering short feedback forms with trainers and trainees at 14 sites in West Virginia, Maryland, Kentucky, and Pennsylvania. Results indicate that goals, methods, materials, and outcomes of existing training programs vary widely among trainers and sites. The report provides less by way of solution to problems, than it highlights the breadth of issues that relate to the question of training effectiveness and quality. The report concludes that additional work by industry, labor, government, and academia is necessary in order to improve health and safety training programs. Recommended steps are: (a) to develop performance standards and measurable criteria in each of the types of mandated training, (b) to develop better training of trainers, (c) to develop expanded training support services. and (d) to undertake further research and development in health and safety training in the mining industry

Jan 1, 1982

By W. J. Campbell

This report by the Federal Bureau of Mines Particulate Mineralogy Unit recommends mineralogical definitions and identification-characterization concepts for selected silicate minerals and their asbestiform varieties. Precise definitions acceptable to mineral analysts, regulatory personnel, and medical scientists are essential because of the present lack of conformity in terminology concerned with measuring and controlling asbestiform particulates and their related health effects. Because of the complexity and variability of crystal morphology in different mineral groups, the descriptive terms are generally explained by illustration rather than by numerical values. Applications and limitations of several analytical techniques for particulate identification and characterization are discussed.

Jan 1, 1977

By John B. Goodman

This report summarizes the work done by the Koppers Company, Incorporated, in cooperation with the Bureau of Mines on the commercial evaluation of the primary low-temperature tars produced from Texas lignite in the Rockdale, Tex., plant of the Aluminum Company of America in conjunction with the Texas Power and Light Company. The interest of the Bureau of Mines in this project is twofold. First, through its cooperative agreement with the Texas Power and Light Company the Bureau has assisted in the technical design and practical operation of the prototype, externally heated, entrained-state carbonizer for producing char for electric-power production and for primary low-temperature tar. Second, the first successful operation of the prototype carbonizers employing the Bureau of Mines-Parry process on lignitic coal in 1953-54 led to the production of large quantities of primary lignitic tar, concerning which too little was known or had heretofore been published in this country.

Jan 1, 1959

By Robert H. Peters

This Bureau of Mines report describes several significant problems associated with absenteeism among underground coal miners. The vast empirical literature on employee absenteeism is reviewed, and a conceptual model of the factors that cause absenteeism among miners is presented. Portions of this model were empirically tested by performing correlational and multiple regression analyses on data collected from a group of 64 underground coal miners. The results of these tests are presented and discussed.

Jan 1, 1987

By Michael T. Nigbor

This Bureau of Mines publication identifies the significant environmental issues associated with the potential development of strategic and critical minerals in the Stillwater Complex, MT. The Stillwater Complex contains deposits of Cr, platinum-group metals (PGM), and Ni. Issues that must be addressed prior to minerals development include the effects mining, milling, and smelting will have on the land, water, and air, and methods of minimizing the environmental impacts.

Jan 1, 1985

By John D. Foulkes

An investigation is made into whether commercially available equipment can be used to engineer effective emergency warning systems for underground coal mines. Discussions with members of the Bureau and the Mining Enforcement and Safety Administration established that the preferred system should operate over the existing Pager Phone twisted pair, and broadcast an audio alarm. Applicable equipments such as voice band tone signaling equipment, alarm sounding equipment, mine telephones and complete alarm systems from over thirty manufacturers are listed. Factors affecting the range over which an alarm could be detected in representative mine situations were studied. These included (a) the subjective masking effects of typical background noise found in mines, such as that due to continuous miners (b) the attenuation of sound in mines (using both a theoretical and experimental results) and (c) the attention-getting qualities of different sound for miners. Audio alarm systems meeting the requirements can be installed and representative systems are described.

Jan 1, 1977

By Francis C. Lincoln

"INTRODUCTION As part of a general investigation of the zinc-producing area of southwestern Wisconsin, the Bureau of Mines undertook a limited amount of exploratory drilling in the immediate vicinity of the New Dale Rundell mine, in the Mifflin District of Iowa County, Wisc.The work was carried out during the early part of 1945, at a time when all effort was being directed toward increasing production of metals important to the Nation's war program. Bureau of Mines engineers decided to conduct exploration at the New Dale Rundell mine after a preliminary study of available data showed a reasonable possibility of indicating an important deposit. Before the Bureau of Mines investigation, 50 holes had been drilled in the vicinity. Of this number, 18 encountered ore of minable grade. Subsequently the mine was developed and operated for a brief period; however, work was stopped before all of the ore disclosed by drilling had been mined. There appeared to be a correlation between the ore shown by the drilling in the New Dale Rundell mine and another disclosure some 1,500 feet to the northwest. The Bureau of Mines exploration was pinned to explore this possible correlation. Of the 7 holes drilled by the Bureau of Mines, 3 disclosed minable ore beyond the limits of previous drilling."

Aug 1, 1946

By Raymond B. Ladoo

The uses for which ground talcs are suited closely depend upon their physical and chemical properties , but , in spite of this fact , little scientific investigation has been made in order to devise quick and accurate tests for the determination of these properties . The chemical properties of talc are inherent and may not be altered or modified except by selective mining or by chemical processes not practical in the present status of the industry . However , the determination of chemical properties is not so important , for most uses , as of physical properties , although sometimes certain chemical characteristics are perhaps unduly insisted upon by chemists in some industries . Physical properties are dependent both upon mineralogical characteristics and upon methods of grinding and sizing and may thus be partly changed or modified by changes in practice . There is so little known of the chemistry and physics of the various processes in which talc is used that the purchase and sale of talc is governed more by rule- of- thumb methods dependent upon individual opinion and often , prejudice , than by accurate , standard tests . This not only causes unwarranted price fluctuations , but injures both the producing and consuming industries by creating false ideas of the suitability of talc for various uses . It thus seems important that present tests be standardized and made uniform for the whole industry , and that new tests devised to fill the existing gaps .

Jul 1, 1920

By Lee J. Raabe

A specialized loading system for tensile and fatigue testing of wire rope was constructed and installed in the U.S. Bureau of Mine Wire Rope Test Facility in Bruceton, Pennsylvania. The computer-controlled closed-loop servo-hydraulic test system which can apply up to 800,000 pounds of force on the rope while stretching it up to 30 inches will be used in the development and verification of hoist rope retirement criteria for ropes in the 1 to 2 ½ in. diameter range. Characteristics and capabilities of the system are discussed.

Jan 1, 1984

By T. W. Smelser

This Bureau of Mines report presents a review of underground testing, test results, and design guidelines of steel-fiber-reinforced concrete (SFC) mine support (cribbing) developed at the Spokane Research Center. The objective of the work was to verify, in field applications, the performance, economics, and acceptance by the mining industry of the SFC supports and establish design guidelines for their use underground. Results indicate superior performance, favorable economics, and enthusiastic acceptance by the mining industry.

Jan 1, 1983

By W. R. Gilliland, G. W. Jones

"One-phase of the accident prevention program of the Bureau of Mines is the determination of the explosion hazards of various combustible gases and vapors encountered,mining and allied industries and the development of means and methods of eliminating them.Gasoline is foremost among the combustible-liquid's as to quantity used and variety of applications in industry, It is a chief contributor to the causes of fires and explosions, taking an enormous yearly toll in property damage and considerable loss of lives.The results presented in this report evaluate the effect of various gaseous inert substances, which owing to their chemical composition, should be of considerable value in the prevention of gasoline fires and explosions. The substances investigated are as follows: Nitrogen (N2), automobile exhaust gas (85 percent N2 + 15 percent CO2), carbon dioxide(CO2), dichlorodifluoromethane (CCl2F2-Freon-12), trichloremenofluoromethane (CC13F-Freon-11), and dichloromonofluoromethane (CHCl2F-Freon-21).The general term ""gasoline"" designates a combustible liquid of such characteristics as to give satisfactory operation without preheating in spark-ignition-type internal-combustion engine. It comprises a complex hydrocarbon mixture having a limiting distillation range and produced commercially by distilling or ""cracking"" crude petroleum or other various petroleum stocks. Small proportions of other substances may be incorporated in the gasoline to enhance its antiknock properties or operating characteristics in internal-combustion engines and to increase its stability during storage, transportation, and use.It is thus seen that gasoline may have rather wide variations of chemical and physical properties, and it would: appear that the results of any investigation dealing with one particular gasoline might not be applicable to other types. However, as indicated by the results given in this report, the inflammable properties of different gasolines at normal atmospheric temperatures are influenced largely the mars volatile hydrocarbons containing 5, 6, 7 carbon atoms- in the molecule, and that the heavier constituent of higher molecular weight have a minor influence on the inflammable properties at ordinary temperatures."

Apr 1, 1946

By H. D. BAILEY, John W. Cole

This paper is one of a series on mining methods and costs published by the Bureau of Mines .. Because of the role, played by the Federal Government in the discovery of the ore body, a description of the exploratory operations of the Bureau of Mines, is included ...

Apr 1, 1948

By H. C. Fuller, E. L. Anderson, F. S. Wartman, M. A. Cook

"This paper gives an account of the production of ductile-grade titanium powder in 100-pound batches by reduction of purified titanic chloride with magnesium, followed by grinding, leaching, and magnetic separation of the reaction product. Apparatus, technique, and methods of controlling product quality are described, and some data on operating costs are given.Although man has been aware of the existence of the element titanium for over 150 years, only recently has the metal itself been available in a form pure enough, particularly with reference to absorbed gases, to allow an estimate of its physical properties. In comparison with mild steel, the tensile strength of titanium is about the same, the resistance to atmospheric corrosion greater, and the specific gravity much less.These properties suggest the usefulness of titanium as a structural material for applications requiring resistance to atmospheric attack and a good strength-weight ratio. Although known reserves of titanium, high-grade enough to be useful at present are not sufficiently extensive to predicate that titanium might supplant iron, aluminum, and magnesium for structural purposes, the reserves are large enough to make its use as a structural material quite feasible in certain fields in which its unique properties are required.As a result of these considerations, the Bureau of Mines station at Tucson initiated an, investigation into the technology of titanium in 1938. First, a critical survey and small-scale trial of virtually all suggested methods7/ for producing the metal was made. The method devised by Kroll8/ seemed best adapted as a source of metallic titanium for, although the purity of the product was not as high as that of products from some other processes, it seemed that modifications in technique necessary for larger-scale production could be made more easily.Essentially, in applying the Kroll process, titanium tetrachloride was reduced to metallic titanium by adding the chloride slowly to molten magnesium contained in a molybdenum-lined iron reaction chamber filled with a protective atmosphere of argon. After reduction to the state of completion desired, the reduction mass and chamber were allowed to cool. Then the chamber was opened, and the reaction mass, consisting of titanium, magnesium chloride, and some unused magnesium, was removed by suitable means. Most of the magnesium chloride and metallic magnesium were removed by leaching in dilute hydrochloric acid. The leached sponge was then ground wet in a ball mill, releached in strong acid, and dried Removal of free iron by magnetic separation completed the production process.Development of the Kroll process by the Bureau was undertaken first at the station at Salt Lake City, in 1942 and the amount formed per run was increased in several steps from a few grams to pounds.9/ In addition to increasing the size of batch over that used by Kroll, the technique was simplified somewhat by the use of unlined reaction vessels."

Aug 1, 1949

By L. D. Schmidt

Now that the war is over, there is a great revival in popular demand to decrease pollution of the atmosphere in our cities. Great cities, such as Pittsburgh, are starting to enforce laws against violators of smoke ordinances. The substitution of low-temperature coke for bituminous coal in household heating is a most promising field for helping to eliminate the smoke nuisance. This Information Circular is written to assist in the very worth-while effort to reduce atmospheric pollution. Herein are de- scribed recent German developments in the production of low-temperature coke. Operating and cost data are given on German commercial-scale low- temperature carbonization plants.

Feb 1, 1947

By William H. King

The Nevada Massachusetts tungsten deposits (fig. 1) are in the Mill City Mining District in north-central Pershing County, Nev., about 37 miles southwest of Winnemucca. Contact metamorphism of thin limestone beds within a series of metamorphosed sedimentaries formed scheelite-bearing ore bodies. These deposits are distributed over a wide area. A Bureau of Mines development program was started January 11 d was completed on July 25, 1941. This work was centered on the outer and less explored beds in the district and comprised trenching, sampling, and diamond drilling. Exploratory work was done in cooperation with the U.S. Geological Survey. Project work substantially increased the reserve tonnage of marginal ore in three of the areas explored and proved the nonexistence of tungsten in a fourth area. The following pages summarize the history of the district, outline property ownership, and describe physical features and ore deposits. The plan and results of the work performed by the Bureau of Mines are presented along with geologic and topographic maps, assay maps, and diamond drill-hole logs.

Jan 1, 1950

By Timothy Y. Yen

This Bureau of Mines report evaluates audio dosimeters, 3 sample units from each of 10 currently marketed brands. Each dosimeter was treated as a "black box" with the acoustic stimulus as the input and the accumulated dosage as the output. The dosimeter microphones were exposed to a sound field gener¬ated in an anechoic chamber. Characteristics evaluated include frequency response (100 to 8,000 Hz), level-time trade-off rate (88 to 117 db), status of calibration, crest-handling capability, and power consumption rate. Experi¬mental errors revealed by replication of the tests were found to be generally much smaller than variations in performance among the samples of any brand, and possibilities of further reducing the magnitude of these errors are discussed.

Jan 1, 1977

By H. B. Salisbury

As a part of a research program designed to help minimize national requirements for new mineral commodities by maximizing recovery of metals from domestic secondary resources, the Bureau of Mines investigated the development of economic methods for recovering copper and associated metals from complex electronic scrap. Three types were selected for research: (1) multiple-pin plugs and connectors, (2) obsolete aircraft radio assemblies, and (3) the magnetic fraction of shredded electronic scrap furnished by the Bureau's Avondale Research Center. The plugs and connectors, after incineration to remove plastic components and melting, yielded a brittle ingot, as did the internal portion of the radio assemblies. The brittle ingots were ground to minus 35-mesh for processing, and the magnetic material was used in the as-received condition. A process using pretreated or raw scrap as a copper precipitant in various concentrations of acidulated copper sulfate solution was developed as a means of effecting an initial separation and upgrading in the form of high-grade cement copper containing all or most of the precious metals.

Jan 1, 1981

By G. Asai

The purpose of this Bureau of Mines investigation was to determine the properties of arc-melted iron-chromium alloys ranging in chromium content from 12 to 50 wt.-pct. Alloys were prepared by consumable-electrode arc melting of electrodes composed of high-purity chromium and high-purity iron. Alloys were fabricated to rod and sheet, and the following data were obtained: Electrical resistivity, hardness, tensile strength, and impact strength at room temperature; and creep-rupture life at 650° C. (1,200° F.). As the chromium content of the annealed alloys varied from 12 to 50 pct., the properties varied as follows: The electrical resistivity increased proportionally from 41 to 53 microhm-cm,; the Rockwell hardness varied from A 38 to A 58; the tensile strength ranged from 52,000 to 96,000 p.s.i.; the impact strength of V-notched charpy specimens varied from 140 to 405 ft.-lb., and the 100-hour creep rupture life at 1,200° F. varied from 5,000 to 16,000 p.s.i.

Jan 1, 1962

By Harry H. Ku

In December 1975, a report entitled "An Evaluation of the Accuracy of the Coal Mine Dust Sampling Program Administered by the Department of Interior" [1] was prepared by the Analytical Chemistry Division of the National Bureau of Standards (NBS), in response to a request by Senator Harrison A. Williams. Chairman, Committee on Labor and Public Welfare. The report attempted to evaluate the adequacy of (1) the personal sampler unit used to measure the coal dust concentration in the mines, (2) the procedures used by the Department of Interior (DOI) to analyze the dust samples obtained from mine operators, and (3) any recent studies made by the Department or private industry concerning the coal dust sampling equipment. Recommendations in the report of NBS included continued research efforts by the appropriate organization to correct the personal sampler deficiencies and to consider the use of area or stationary samplers as a supplement to the personal samplers. Concurrent with the NBS report cited above, the General Accounting Office (GAO) also issued a report in December, 1975 [2], suggesting that improvements are still needed in coal mine dust sampling programs and procedures relating to penalty assessments and collections. Among recommendations made by GAO, the following paragraph specifically called for actions by the agencies involved:

Jan 1, 1979

By W. R. Hardwick

This paper describes mining methods and practices of the Chino Mines Division, Kennecott Copper Corp., Grant County, N. Mex. It is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. A similar program was conducted from 1928 to 1939, which helped to improve the efficiency of mining operations. The primary purpose of the program is to promote development and conservation of our mineral resources by disseminating technologic information on methods, practices, and related features in mining mineral deposits. It is expected that the program will: (1) Promote efficiency in operating mines; (2) assist operators and engineers in evaluating and developing new mineral deposits; (3) provide data for engineering curriculums in mining schools; and (4) furnish performance and cost data for revising engineering handbooks and for inclusion in engineering textbooks.

Jan 1, 1958