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By Kathleen M. Kowalski, Audrey Podlesny

The Maslach Burnout Inventory (MBI) was administered and scored for 154 Mine Safety and Health Administration (MSHA), U.S. Department of Labor, employees who serve as accident investigators for serious accidents and fatalities as part of their job duties. The subjects responded anonymously during a workshop on stress. The subjects consisted of randomly selected individuals, representative of locations across the country and representative of all mining commodities: coal, metal, nonmetal, stone, and sand and gravel. The Maslach Burnout Inventory assesses three aspects of experienced burnout: emotional exhaustion, depersonalization, and reduced personal accomplishments. The average results of the scores for each of the three subscales fell in the moderate range for the study group of MSHA accident investigators. The scores within the moderate range show that the subject population was at the lower end of the range for emotional exhaustion and depersonalization, tending toward a lower burnout risk, while the group evidenced a lower sense of personal accomplishment in their jobs, indicating a higher risk for burnout. It is concluded that overall this group is at moderate risk for burnout, and the authors recommend follow-up with this population.

By N. W. Lord

The experimental work reported upon herein was performed at the laboratory of the United States fuel-testing plant on the grounds of the Louisiana Purchase Exposition at St. Louis, Mo., between Janu- ary 1, 1905, and July 31, 1906, and was undertaken for the purpose of checking the results obtained in the routine work of the laboratory, improving the methods of working, and investigating the chemical and physical properties of coal. The laboratory having been designed primarily for the analysis of the coal samples sent to the fuel-testing plant, as well as those taken in connection with the regular testing operations of the boiler, gas-producer, and other divisions of the plant, only a very small proportion of the time of the force was available for experimental work outside of the regular routine. From the nature of such work it was not possible to separate the results obtained in 1905 from those obtained in 1906, especially as many of the experiments, such as those on the alteration of coal, involved a long time and were started in 1905 and continued to the middle of 1906. This report therefore covers all such work up to its completion in July, 1906. The complete history of the coals used in these experiments is not given, the samples being usually referred to by their laboratory num- bers only, as such information is generally not necessary and does not affect the interpretation of the results obtained in the experiments. Fuller information as to any particular sample may be found in the published reports of the fuel-testing plant for 1905 and 1906. In the following pages the results of each line of experimental work are given under a special heading indicating the object of the investigation.

Jan 1, 1911

By N. W. Lord

This volume contains the descriptions of the samples whose analy- ses are published in the preceding volume, Part I of this bulletin. The descriptions have been compiled from the notebooks of the per- sons who collected the samples, have been condensed from accounts given in published reports of the United States Geological Survey, or have been furnished by the collectors themselves. Inasmuch as the descriptions represent the work of many persons during a period of six years, and inasmuch as they were recorded under widely differing conditions, they necessarily vary in fullness of detail. The descriptions are published for two purposes: (1) To prosent such information regarding the character of the coal, the impurities in the beds sampled, and the nature of the roof and the floor of the beds as has a definite bearing on the significance of the analyses of the samples, and (2) to give any supplementary details such as the capacity or the output of a mine, the method of mining and prepar- ing the coal, and the chief uses to which it is put, that may be of assistance to Government engineers or purchasing agents, and to other persons, in preparing specifications and awarding contracts for fuel.

Jan 1, 1913

By A. E. Wells

A critical study of the wet Thiogen process for extracting sulphur from the smoke of smelters is one of several investigations related to the general smelter-smoke problem that are being conducted under the direction of the Bureau of Mines. Part of the work done in the pyrometallurgical section of the cooperative metallurgical exhibit of the Bureau of Mines at the Panama-Pacific International Exposition during 1915 related to this investigation, and at the expiration of the exposition, the work was continued in the labora- tories of the Bureau of Mines in the Hearst Memorial Mining Building of the University of California, Berkeley, Cal., where a mining experiment station of the bureau has been established under the cooperative agreement with the University of California. Early in the spring of 1915, when plans were being made to co- operate with several metallurgical interests, the Thiogen Co. proposed to the Bureau of Mines that, along with the studies of various pro- posed methods for eliminating sulphur dioxide from smelter smoke, there should be included a study of the wet Thiogen process. In the study as outlined it was proposed to determine whether it would be technically and commercially feasible to use the, process for the recovery of elemental sulphur from the sulphur dioxide in waste smelter gases. Although there had been no large-scale work with the process, either in the laboratory or at a smelter, representatives of the metallur- gical and mining industry had shown considerable interest in the proposed method, and the desire had been expressed that a better knowledge of the possibilities of the process should be obtained. Thus, cooperation with the Thiogen Co. seemed justified by the in- terests of the metallurgical industry, and by the conservation promised by the recovery of a product of market value from what is otherwise a waste, and in some instances a serious nuisance. In accepting the responsibility for directing this investigation, the officials of the Bureau of Mines were necessarily free to conduct the work in the manner they considered necessary to determine the facts. It was also understood that any information obtained was to be made available to all who might be interested and might be printed in a Bureau of Mines report. To cover the cost of laboratory equipment and supplies, and the payment of salaries of assistants, other than Bureau of Mines employees, the Thiogen Co. in May, 1915, deposited with the cooperative metallurgical exhibit fund a sum considered sufficient to warrant starting the laboratory investi- gation. The origin and organization of this fund has been described by Clevenger and the author." In outlining the program for this investigation it was hoped that ultimately a small complete plant would be erected and the investi- gation center around the operation of the plant. However, pre- liminary to the erection of the plant, a laboratory study of the proc- ess was considered necessary, as the technical features of the process could be determined, it was believed, as satisfactorily on a smaller scale as on the scale first proposed. However, it was realized at the time that it would not be possible to determine so satisfactorily or definitely the commercial possibilities of the process on the scale of work adopted as in the larger operating plant. With this fact in mind it was planned that, if the study of the technical features on a laboratory scale gave sufficient promise of the process being commer- cially feasible, an operating unit should, if possible, be constructed later, and that more definite information concerning the commercial prospects should be determined. The investigations were started in June, 1915. In June and July work was confined entirely to small-scale laboratory tests, in which a careful study of the chemical reactions involved was made. In August, tests on a larger scale were started, and these were con- tinued until December, small-scale tests being made at the same time. On December 1, 1915, all work on the Thiogen process was discon- tinued temporarily, as the close of the exposition necessitated moving the laboratories. Work on the Thiogen process was started again in January, 1916, in the laboratories of the new mining experiment sta- tion at Berkeley, Cal., and was continued during the spring of 1916 until a point was reached where it was felt that the essential parts of the process had been carefully covered, and that some definite state- ments concerning the technical features and possibilities of the process, as given in this report, were warranted.

Jan 1, 1917

By E. A. Barrett, L. L. Rethi, B. Fotta

Employment and accident trends of independent contractors working at coal and noncoal mines in the United States are reported. Data include employee hours and accidents, both fatal and nonfatal, from 1985 through 1994. Also noted are increases or decreases in certain accident classifications and accident rates, particularly those which have shown significant change during the ten-year period.

By E. W. Dean

The Bureau of Mines is engaged in the work of obtaining data regarding the physical and chemical properties of typical crude oils from the various producing fields of the, United" States. Preliminary reports have been published that cover the eastern fields* and the' Rocky Mountain districts.** Since the appearance of these, reports: it has been suggested that certain additional data. I regarding the samples would be of practical value. It was believed that a knowledge of the viscosity of crude oil was desirable, particularly in connection with the design and operation of pipe lines. In accordance with this suggestion, the authors have made viscosity tests upon as many of the samples of the two series as wore still available for examination. Determinations were made at temperatures of 70° and 100°F., and in addition the oils were Subjected to the A. S. T M, pour-test*** to as certain the lowest temperatures at which they remain in a fluid condition.

Jan 1, 1921

By Ted C. Briggs

A removable-jacket distortion apparatus was constructed and used to measure distortion coefficients for two high-pressure vessels. The measured distortion coefficients were used to compute distortion coefficients for volumes VI and (V1+V2) of a 1,000-atmosphere Burnett compressibility apparatus for the temperature range 0° to 75° C. Young?s modulus for Armco 17-4 PH stainless steel, heat treated to condition H1150-M, was computed from experimentally determined distortion coefficients. A 10-to 14-percent correction to the values obtained for Young's modulus may be required because pressure vessel end effects were neglected. The distortion coefficients of the compressibility apparatus are believed to be accurate to about 1 percent.

Jan 1, 1970

By Fred N. Kissell

Methane flows and pressures were measured in mines in the Pittsburgh, Hartshorne, and Pocahontas No. 3 coalbeds. From the data, the permeability of each of these coal beds was computed. It was found to depend strongly on the type of coal and on the amount of water in the coalbed, and it was found to increase with time. All of the coalbeds had a high-permeability zone adjacent to the face or rib, and the Pittsburgh bed exhibited directional anisotropy. Surprisingly, little or no overburden effect was observed.

Jan 1, 1972

By R. R. Brandenthaler

A series of open-flow tests was conducted in the Chickasha gas field, Grady County, Oklahoma, during June, 1927, under the direction of the U. S. Bureau of Mines and at the request of the Oklahoma Corporation Commission. The purpose of these teats was to determine whether or not any differences existed in the open-flow volume of a gas well when taken through well-head nipples of different diameters, and further, to establish if possible a relationship between open-flow volumes taken through well-head nipples of various diameters. The open flow of a well is the volume or quantity of gas, measured under standard conditions, that a well will produce when open to the atmosphere. There are several methods used for determining the open flow of wells; some of the methods are more suitable under certain conditions than others. The Pitot tube method is the simplest, is applicable to almost any condition, and is the one most commonly used. In the tests described in this paper no attempt was made to compare the Pitot tube method with the minute pressure measurement method or the orifice measurement method.5

Jan 1, 1928

By H. H. Schrenk, L. B. Berger

"INTRODUCTION The Bureau of Mines frequently receives requests for information and advice regarding the equipment necessary for establishing laboratories for the analysis of mine atmospheres. Such requests are made by mining companies, State mining departments, and other agencies concerned with the safety of mining operations. In many instances it is desired to install a complete laboratory, which will necessitate purchase of suitable gas-analysis apparatus and all the minor but important accessory equipment needed to carry on this type of work. Although publications that describe methods and techniques applicable to the analysis of mine atmospheres are available, it is not within the scope of such publications to give detailed information on laboratory equipment or design. Persons unfamiliar with laboratory practices and gas-analysis procedures may find it difficult to decide upon the proper equipment for their particular needs and to itemize the various accessories that must be obtained to set up a complete laboratory.The purpose of this circular is to discuss the different types of equipment that may be used in the analysis of mine atmospheres, with particular regard to the application and limitations of each type. Information on the various accessory equipment needed in a laboratory for the analysis of mine atmospheres is given also, and suggestions on laboratory design are included. As much of the necessary equipment may be obtained from laboratory supply houses, the information should aid in arriving at estimates of the cost of proposed laboratories.The procedures involved in the analysis of mine atmospheres are not described; such information is contained in publications referred to in this circular."

Feb 1, 1948

By Ann G. Kim

Methane in coal constitutes a serious hazard during mining. Draining the methane from large blocks of coal in advance of mining is an effective method of improving the safety and efficiency of coal mining. Because of the similarity of the two gases, drained methane can be recovered and added to pipeline supplies of natural gas. To effectively apply advance drainage techniques and recover drained gas, a gross estimate of the methane content of coal is necessary. Using data from previous investigations, the virgin reserves of the Pittsburgh coal in the central and southwestern parts of Washington County, Pa., are estimated at over 1.5 billion tons, with a methane content of 50 to 100 fts/ton. The Pittsburgh bed in this area of approximately 265 mi2 contains over 130 billion ft3 of methane.

Jan 1, 1974

By Ann G. Kim

Methane in coal constitutes a serious hazard in coal mining. Draining the methane in advance of mining can mitigate this hazard, conserve energy, and offer economic benefits. This Bureau of Mines report evaluates the Pittsburgh coalbed in Greene County, Pa., to determine if advance drainage is feasible. The gas content of virgin reserves in Greene County is estimated at 100 to 200 ft3/ton, a total of over 370 billion ft3 of gas in an area approximately 310 mi2. Because of the similarity to natural gas, drained coalbed gas could be recovered and added to pipeline supplies of natural gas. The value of conserved gas would offset the cost of drainage and extend energy resources.

Jan 1, 1975

By Paul W. Jeran

Subsidence was monitored by the U.S. Bureau of Mines over the ends of longwall panels operating in the Pittsburgh, Kittanning, and No. 2 Gas Coalbeds of the northern Appalachian Coal Basin. The final subsidence over the finishing ends of three panels in the Pittsburgh Coalbed are compared with the subsidence measured over the rib at these panels. The characteristics of subsidence are different. At Mine A, data over the start of a longwall panel shows similar characteristics to the subsidence measured over the rib. Subsidence over the fmishing ends of panels in the Kittanning and No.2 Gas Coalbeds are also different from the subsidence over the rib. The use of a subsidence prediction model based on data gathered over the rib of a panel will not yield accurate results if it is applied to the finishing end of a longwall panel. Acceptable results may be obtained along the centerline over the starting end of a panel.

Jan 1, 1991

By R. H. Lien

The Bureau of Mines, U.S. Department of the Interior, has developed a flue gas desulfurization process as part of its goal of minimizing the undesirable environmental impacts associated with energy and mineral-processing plants. This process, known as the citrate process, involves absorption of sulfur dioxide (SO2) in a buffered solution of citric acid. The S02-loaded solution is regenerated by reaction of the S02 with hydrogen sulfide (H2S) to form elemental sulfur. As an adjunct to the citrate process, bench-scale research has shown that S02-loaded citrate or glycolate solutions can be regenerated by countercurrent contact with steam (stripping) in packed towers. Concentrated S02 is produced by condensing the steam from the stripper product. Thus, steam stripping provides strong S02 gas for liquefaction, sulfuric acid production, or reduction to elemental sulfur. Stripping steam requirements were determined for treatment of 0.25-, 0.50-3 1.0-, and 2.0-pct-S02 waste gases. Steam requirements decreased with increasing S02 concentration n the simulated waste gases. For example, 5 grams of steam per gram o S02 was required to remove 90 pct of the S02 from a simulated copper smelter gas (2.0 pct S02), while 30 grams of steam per gram of S02 was needed for 90 pct S02 removal from a simulated coal-fired powerplant gas (0.25 pct S02).

Jan 1, 1979

By David C. McHuron

The U. S. Bureau of Mines in their continuing research into sealants, selected MBAssociates to design, build, and test equipment and evaluate sealant as to its effectiveness is shale degradation. There were 20,050 sq.ft. of coal mine roof sprayed with a mine sealant and as a result, it has been estimated that the sealant coated roof has from 50% to 95% less roof falls than that roof which was not coated with sealant.

Jan 1, 1980

By H. K. Kutter

The pressure pulse generated by an underwater spark \vas investigated in relation to its potential use for rock fragmentation. The study established (1) the relation between the peak discharge current and the peak wave pressure; (2) the relationships among the peak wave pressure, the discharge voltage, and the spark gap width; (3) the type and pulse duration of the generated wave; (4) the percentage of energy transmitted in the spark as a function of spark gap width and discharge voltage; and (5) the percentage of energy converted into the pressure wave as a function of gap width and discharge voltage. Spark-generated fractures were studied in two-and three-dimensional rock and plastic specimens. The laboratory results indicated that the pressure pulse generated by an underwater spark is a potential practical tool for rock fragmentation. The paper contains an appendix describing the capacitive pressure gage specially developed for the laboratory tests.

Jan 1, 1969

By Robert J. Anderson

"Introductory Statement.In founding any kind of castings, even with the best practice, scrap castings are produced because of rejections for certain defects. Casting los¬ses are a serious source of financial loss in iron and steel foundry practice as well as, in brass and bronze, but they are particularly serious in aluminum foundry work because of the high value of aluminum. The indications are that in many aluminum foundries in the United States, the casting losses are at times high, and in some plants they are entirely too high when compared with average practice. Of course, defective castings have a residual value for remelting, but if much machine work has been done on a casting before it is scraped, the labor costs alone may exceed the value of the metal and even that of the rough casting.In a foundry, the monetary losses incurred through the production of waster castings can be ascertained from calculations based upon adequate scrap-loss reports. Such reports, when properly kept and interpreted are a valuable aid in finding foundry costs, but they are primarily useful in diagnosing the causes for casting losses. Many aluminum foundries in the United States do not keep adequate records of strap losses; as a result the causes for defective castings can not be traced, nor preventative measures adopted. However, some of the large aluminum foundries keep excellent records, and it has been found that these involve little extra expense for clerical work. If a foundry man will study his daily production of defective and waster castings, he will be able to trace the causes or losses and then make such corrections in his plant practice as will effect a considerable reduction in these losses -- as much as 50.0 per tent in some foundries. If all the present casting losses of the United States could be reduced 50.0 per cent, by eliminating only the readily preventable defectives, a saving of several million dollars would accrue. In the aluminum-foundry industry alone, the saving would amount to about $600,000."

Apr 1, 1920

By J. H. Perry, Joseph Cervik, G. N. Aul

The Bureau of Mines is conducting research to determine the effectiveness of long holes in degasifying an area of the Upper Split of the Lower Sunnyside coalbed at Kaiser Steel CO.'s Sunnyside No. 1 mine. These holes were drilled from the two outside entries of a section that was closed to mining because of excessive methane emissions. Two holes drilled to 430 and 450 feet produced initial gas flows of 160,000 and 127,000 cfd, respectively. Sixteen days after the completion of the second hole, the total gas production declined to just over 144,000 cfd. In 9 months of degasification, over 35 MMcf of commercial-quality gas has been removed from the coalbed. The combined gas flows declined to 106,000 cfd in the 9-month period. The two holes have reduced face emissions by about 40 pct.

Jan 1, 1978

By Forrest T. Moyer

Injury experience in the mineral mining and processing industries during 1968 was slightly improved in the nonfatal-injury record but worse in the fatality record. The resulting frequency rate of all injuries was slightly better, whereas the injury-severity rate retrogressed appreciably from the figure for 1967. Overall operating activity, as measured by man-hours of worktime, was slightly higher in 1968. However, there were several major segments of the mineral industries in which activity was lower owing to reduced demand for mineral products and to several major work stoppages. These statistics comprise the injury and work experience of all personnel engaged in production, exploration, development, maintenance, repair, and force-account construction work, including supervisory and technical personnel, and working partners and owners at mineral-producing and mineral-processing establishments in the United States. Data concerning officeworkers are excluded except for the oil and gas industry for which such information is not separable. All injury rates and totals are calculated from data before rounding. The data for 1968 are preliminary except for the anthracite, coke, petroleum and natural gas, native asphalt, peat, and slag industries, which are final. The figures represent full coverage for all industries except oil and gas for which coverage is not complete, particularly with respect to small companies.

Jan 1, 1970

To identify the most successful methods now in use for controlling respirable dust in longwall mines using double-drum shearers. Approach Conduct dust surveys at six longwall mining sections that use double-drum shearers and are regularly in compliance with the Federal Respirable Dust Standard, to identify effective dust control techniques. The selection of mine sites was based on recommendations provided by the Mine Safety and Health Administration. Instantaneous and short-term gravimetric instrumentation make it possible to isolate longwall dust sources and to determine the effectiveness of dust control techniques. (These procedures were developed by the Bureau of Mines, and are described in detail in Technology News Bulletins 134 and 135.) Production levels, and seam heights at each of the six longwall sections were: 53", 700 tps; 60", 800 tps; 72", 1000 tps; 79", 1500 tps; 84", 2000 tps; 96", 1500 tps. Survey Results Three effective dust control techniques were identified. 1. Shearer Operators on Intake Side of Lead Drum-At all mines surveyed, an important factor in controlling dust exposures at the shearer is the use of a cut ting sequence that allows the shearer operators to work most of the time on the intake air side of the lead drum. Dust profiles, like those plotted from data at two mines (see the graphs), show the large gradient in dust concentrations that can

Jan 1, 1982