Search Documents

By H. Foster Bain

Ten years ago there was no general , country-wide service for the systematic training of miners in matters relating to safety . A beginning only had been made at a few scattered points . Under the old conditions each man was left largely to look out for himself in meeting the hazards of his day's work, and the foreman , shift bosses , and superintendents chiefly relied upon improvision when major accidents occurred . So long as the mines were small and the workers highly intelligent and well trained in routine mining methods , and when too , the pressure for output had not yet speeded up industry to the extent it has since those days , there was something to be said for this lais- sez faire attitude . When , however , the rapid expansion of industry lead to the introduction of new and little trained labor and to units of production of greatly increased size , the natural dangers of mining were greatly intensified . An accident in a small mine affects only a few; the same accident in a large mine , unless proper precautions have been taken , may cost the lives of many . The public does not generally recognize that the greatly increased outputs of the mines , of coal mines in particular , have been in recent years , obtained from substantially the same number of miners as ten years ago but with a personnel not nearly so well trained in mining . It is inevitable under : such conditions that more care must be devoted to avoiding accidents and much more elaborate preparations made for meeting them . In the years immediately preceding the establishment of the Bureau of Mines this speeding up of industry , change in the character of mine labor , and increasing hazard had all begun to be felt . Immediately prior to the organization of the Bureau of Mines , public attention had been drawn to a series of disastrous coal-mine explosions , to the increasing frequency of these disasters , and to the terrible loss of human life . resulting therefrom. One of the first problems , therefore ; confronting the Bureau was clearly that of finding methods of reducing the number of such disasters and lessening the severity of those that continued to occur . Toward this object were immediately directed the energies not only of the Bureau of Mines but also those of State mine inspectors , mine operators and various other agencies , all of whom were urged to cooperate in this great humanitarian work. The results of this work naturally cannot be measured by figures only . Work for increasing the health , safety , comfort , and happiness of human beings may not be gaged with mathematical precision . But certain features of this work as revealed by the record from year to year are of much interest . ”

Apr 1, 1921

By Murray Weintraub

The Bureau of Mines investigated the aerodynamic factors that control the functioning of the blowcase devices used in pneumatic processes for dispersing solids. Alumina powder of 8-micron mass-mean diameter was placed in 0.75- inch-diameter by 10-inch-long cylinders} and a blowcase technique was employed. It was determined that dimensions and gas rates for discharging the powder from the cylinder by a stream of gas may be calculated by assuming a fluidization mechanism and extrapolating residues to a desired finite quantity or to zero at the terminal velocity. The state of agglomeration of a powder at discharge may be determined from measurements of the velocity required for zero residue.

Jan 1, 1967

By Sivalingam Jeevan, R. L. McConnell

Ground check monitors may be made in several configurations. Each type has unique characteristics and provides different safety attributes when applied to different mine situations. In this paper, the monitor types are discussed in relation to the mine situations. It is shown that the selection of the monitor type can have a significant effect on the safety of the resistance grounded power system. The options are discussed, and the conclusion is drawn that only one monitor configuration can provide maximum safety. Unfortunately no monitors of this configuration are presently available. In addition, when the monitor capabilities and ground wire configurations are considered as a system, it can be shown that certain configurations will lead to maximum safety. This work was supported by U.S. Bureau of Mines grant G0144138.

Jan 1, 1979

Provide an accurate, simple, alternative means of evaluating the safety of mine electrical ground systems which has little or no negative impact on mine productivity. The Traditional Evaluation Method The Code of Federal Regulations requires all mines to safely ground their power systems to earth. Effective earth grounding reduces shock hazards to mine workers operating electrical equipment, protects equipment from damage by voltage transients, and provides a means of detecting and locating ground faults. Once an earth ground bed has been constructed, its level of resistance has traditionally been used to gauge the safety of the entire grounding system. Bed resistance measurements are normally performed using a ?fall of potential? technique with a current return electrode placed at a remote location, If the resistance measured is acceptably low, then the bed is assumed safe.

Jan 1, 1985

By Hylton R. Brown

Advertisements and articles in technical and trade journals announce the approach of a new age, in which plastics, light metals, laminated wood, and numerous other products or byproducts will be used in the construction of automobiles, airplanes, and furniture and equipment used in our factories, offices, and homes. Undoubtedly, after the war there will be many such developments which will introduce new manufacturing methods and new hazards to challenge the safety engineer. Already we know, from experience in laboratories and pilot plants where these new products are being tested, that there will be many fire and explosion hazards to be overcome. The danger of dust explosions may be one of the principal hazards, because thetic resins and other materials used in the plastics industry, as well as metal powders, wood dust, and other finely divided substances, are capable of forming explosive mixtures in air. Heavy losses of life and property have been caused by dust explosions in flour and feed mills, starch factories, and grain elevators, and it will be well to consider the possibilities that such losses may occur in any new industry and to provide all possible safeguards against hazards. Fortunately, we have learned something about the behavior of dust explosions and know something about the ease of ignition, limits of Explosive concentration, end pressure developed. Our efforts should now be directed toward the application of this knowledge in the development of safe operating practices.

Jan 1, 1945

By A. L. Murray, C. A. Allen

"The Industrial Commission of Utah from a study of the accidents (especially the fatalities) occurring in connection with mining in the State was struck by the large number arising from lack of due care on the part of the employee injured or carelessness on the part of some fellow employee. Figures show that approximately 40% of the deaths are due to carelessness as against only ) 10% or 12% that can be laid to faulty conditions in the mines. With a view to reducing the number of these accidents an intensive campaign of education was inaugurated, conducted jointly by the Industrial Commission of Utah and the United States Bureau of Mines.Through the cooperation of the U. S. Bureau of Mines, Mine Rescue Car No. 11 operating in Utah has been utilized as the means of carrying on the campaign. In making the regular training visits to the mining camps of Utah the crew of car 11 was authorized to include with the courses of instruction in Mine Rescue and First Aid, safety and health rallies, foremen's safety meetings, and appeals carried on through the public schools to stimulate an awaking of personal responsibility of miners and their familiar' in safety and health endeavor. The work was placed under the direct charge of Dr. Murray who has had previous experience in similar work and brought to the campaign helpful enthusiasm. He was assisted by Bruce Johnson, fore¬man miner of Car 11, who had been safety engineer for the U. S. Smelting Company, and R. W. Clark, first aid miner of Car 11. The expense of providing posters, literature, pledge cars, buttons, rental of special educational films and incidental expenses of foremens' meetings has been born by the Industrial Commission.Plan of the Campaign.In planning the campaign the main object was to revive as much as possible, among the workers, a spirit of responsibility for safety. Any considerable reduction of preventable accidents can be accomplished only through the workers themselves who are responsible for such accidents, therefore, the more personal the application could be made to all the workers the greater the accruing results would be."

May 1, 1921

By Charles T. Chislaghi

An economical, remotely operated (automated), temporary roof support (ATRS) has been developed by the Bureau of Mines for use on a single, fixed-head roof-bolting machine (squirmer) that operates in low coal seams (less than 42 in thick). The ATRS eliminates the need for squirmer operators and helpers to go under unsupported roof to set or remove temporary support prior to or during the roof-bolting cycle--a task that annually accounts for approximately 20 pct of all roof fall fatalities. The ATRS can be adapted to any squirmer used in the U.S. low coal fields. A prototype ATRS was field-tested at Imperial Colliery Co.?s Mine No. 20 in Eskdale, W. Va. The Mine No. 20 amended roof- control plan, which requires the use of the Bureau?s ATRS as temporary support during face bolting, has been approved by the Mine Safety and Health Administration (MSHA), U.S. Department of Labor.

Jan 1, 1982

By Sean Gallagher, Rhys Llewellyn, Jay Mattos

This paper contains the results of an examination of accident, injury, employment, and production information reported to the U.S. Department of Labor's Mine Safety and Health Administration (MSHA) and provides information on some of the measures longwall mine operators are using to prevent accidents In all industries, technological advances play a key role in determining those who will survive as competitive participants in an increasingly global marketplace. While mining is among the most basic of industries, technological change is neither unfamiliar nor unwelcome to miners. Historically, technological advances in mining, particularly coal mining, have tracked closely with fluctuations in demand. In the early 1900's, coal accounted for more than three quarters of all the fuel consumed in the U.S. To meet this tremendous demand, underground cuffing machines were introduced, resulting in faster, more efficient coal extraction. Transporting coal to the surface, however, remained labor intensive. In the 1920's, nearly all underground coal was still being hand loaded. Demand for coal then declined as the price of oil, natural gas, and electricity became competitive. In the late 1930's and throughout the duration of World War II, coal demand and production was high. By 1940, more than half the coal mined was being mechanically conveyed to the surface. In 1948, the continuous mining method was introduced in the U.S., further accelerating the extraction process. By the 1950's and 1960's, however, coal production again declined as railroads converted to diesel fuel and gas and oil provided a larger share of the home heating market. Underground coal mines required even more mechanization to remain competitive as an energy source. The first longwall system was introduced in 1960. By 1995, longwalls were producing more than 189 million tons of clean coal annually, surpassing continuous mining production for the second straight year. The mining of coal and other materials has not come without a huge loss of life and considerable human suffering. More than 103,000 workers died from injuries in U.S. mines in the last 85 years. Between two and three thousand miners died each year from the turn of the century until 1931, many from underground fires and explosions. The U.S. has witnessed a tremendous drop in fatalities in underground coal mines. Credit for that is due to safety inspections and enforcement activities, better safety awareness and practices among management and labor, improved ventilation, the use of safer equipment, and increased mechanization which removed many miners from the hazards at the face and also reduced the size of the mining work force. There is little doubt that longwall mining has greatly increased underground coal mine productivity. The degree to which longwall mining has contributed to a safer work environment for underground miners is more difficult to ascertain.

By Stephen A. Swan

Bureau of Mines researchers have collected and evaluated rollover protective structures (ROPS) f or more than 10 yr. ROPS and falling object protective structures (FOPS) are required on specified mining machines under regulations of the Mine Health and Safety Administration (MSHA). Both ROPS and FOPS are required on mining machines used in surface coal mines and surface areas of underground coal mines (30 CFR 77.403 and 7 7.4 13a), and ROPS are required on mining machines used in metal and nonmetal mining operations (30 CFR 55, 56, and 57.9-88). This illustrated manual provides mine safety personnel, MSHA inspectors, and original-equipment manufacturers with guidelines and a check- list for inspecting ROPS being used in the field. The manual discusses specific requirements of the MSHA regulations and minimum inspection and maintenance checks for ensuring compliance with those regulations. An easily reproducible checklist is provided as an aid to the inspection of ROPS.

Jan 1, 1985

By John T. Aydelotte, Martin J. Gavin

" Oil shale contains little or no oil as such , but it contains an organic material from which oil may be produced by destructive distillation" . This statement , or others conveying the same meaning, appears in many popular and techni cal articles on oil shale . It is based on the belief that the ordinary solvents of petroleum have but little action on the organic substances contained in oil- yielding shales , although on distillation these same shales may yield upwards of 50 gallons of crude shale oil per ton . A 50 - gallon shale thus yields by distillation 18.73 per cent of its weight as oil ( assuming the specific gravity of the oil to be 0.900 ) , although only a relatively small part of this can be recovered by extraction with such solvents as chloroform , carbon tetrachloride , and the like . In the course of certain experiments designed to determine the solubilities of different shales after they had begun to yield oil by distillation , it was found desirable to determine the quantity dissolved from certain unheated shales by various solvents , at or near the boiling points of these solvents . The method used and results obtained are presented below. These experiments were made in connection with the oil - shale investigations being conducted by the U. S. Bureau of Mines , in cooperation with the States of Colorado and Utah .

Jan 1, 1922

By R. V. Ramani, R. Stefanko, G. W. Luxbacher

CALCULATION OF MINE HEAD LOSSES FROM ALTIMETER SURVEY DATA USBM PENNSYLVANIA STATE UNIVERSITY - MINERAL ENGINEERING DEPARTMENT USBM USBM USBM THIS PROGRAM CALCULATES PRESSURE LOSSES USING THE USBM METHOD GIVEN USBM IN USBH IC 7809 BY MCELROY AND KINGERY.1957. THE MAJOR DIFFERENCE USBM BETWEEN THIS PROGRAM AND THE CITED REFERENCE IS THE TREATMENT OF AIR USBM

Jan 1, 1977

By J. R. Bartels

Operation of underground coal mine mobile equipment is usually done in a restricted workspace with reduced visibility. This work environment puts machine operators in awkward postures for tasks that require awareness of their surroundings and fast reactions to avoid hazardous situations. Using experienced equipment operators as a source, researchers conducted an investigation that developed a method to gather data on the needs and practices of machine operators while controlling the machine and the reasons for needing particular operational cues. The method used was an interview technique including a survey questionnaire and visual aids. The data gathered defined operator cues and work positions for the cutting and tramming phases of remote controlled continuous mining machines used in underground coal mines. Analysis techniques to determine which cues an operator sees from a variety of positions utilizing a computer simulation is shown to be potentially useful to the mining industry for design of work practices and workplace layout and could impact equipment design and selection for improved worker safety. Conclusions indicate that the survey was a good research tool to collect data and helped investigators understand important visual cues. Using this information, researchers were able to analyze the visual cues an operator can see from a given work position and posture.

Jan 1, 2009

This report summarizes the work performed by the Bureau of Mines on the development of analytical procedures for determining metallic and interstitial impurities in high-purity tungsten. Fourteen published methods and seven unpublished methods are briefly described. Carbon, hydrogen, nitrogen, and oxygen, in microgram to higher quantity levels, can be determined by several methods. Trace levels of 29 metallic impurity elements can be determined by optical spectrography, X-ray spectrography, and other instrumental methods.

Jan 1, 1968

By THEO L. JOHNSTON

In preparing for war , Japan built an iron and steel industry that ranked high with other industrial nations . Deficient in raw materials for making iron and steel , it had to acquire the bulk of its iron ore and much of its coal and scrap iron from foreign sources . Steel manufacture, and fabrication , however , were reserved mostly for the Home Islands , where modern integrated plants produced the implements of war . The vulnerability of relying on imports during the war was recognized early, and steps were taken to exploit iron-ore deposits and develop treatment processes on the Home Islands in order to be as self - sufficient as possible . Although the industry had expanded considerably, the capacity of the large plants still was insufficient for military requirements, so other meth- ods of producing iron and steel were adopted, which in some ways illustrate the desperate effort made to supply the war machine. In developing the iron and steel industry, modern practices of other countries were studied and followed with modifications to suit Japanese con- Aitions. German and American technical ability and equipment played a large part in the program; however, the Japanese had competent furnace technologists capable of obtaining proper equipment performance. For the most part, the standard practice consisted of smelting iron ores in blast furnaces and then refining the pig iron to make steel in open-hearth furnaces. Electric furnaces played an important part, especially in the manu- facture of alloy steels. Various other methods yielded minor but significant production. Among the various other treatment processes used, the production of sponge iron in rotary kilns 'probably was the most important in producing melt- ing stock for steel making. Of special importance was the fact that sponge iron made from low-grade ores contained critical metals, such as nickel and chromium, so that the results were more significant than was generally believed.'

Mar 1, 1948

By N. S. Dalal, X. Shi

"It has been recently suggested that the exceptionally high antitumor and antibacterial activity of natural fredericamycin A (FMA) is related to its ability to spontaneously generate the superoxide anion (02-) and hydroxyl (""OH) radicals in aerobic solutions [Hilton, B. D., Misra, R., & Zweier, J. L. (1986) Biochemistry 25, 5533]. With a view to understand the mechanistic details, attempts were made to reproduce earlier electron spin resonance (ESR) evidence for the oxygenated free radical formation in well-aerated solutions of natural FMA in dimethyl sulfoxide and dilute H 20 2• Little or no evidence was obtained for the formation of the 0 2- and methoxy (""OCH3) radicals, while the detected formation of the 'OH and methyl ('CH3) radicals was attributable largely to mechanisms not involving FMA. These results thus reopen the T question regarding the mechanism of its exceptionally high tumoricidal-bacteriocidal activity. This paper reports on an electron spin resonance (ESR) investigation of the formation of oxygenated free radicals in solutions of natural fredericamycin A (abbreviated as FMA) which has recently been reported to be a highly potent anti¬tumor antibiotic (Pandey et al., 1981; Warnick-Pickle et al., 1981). The impetus for this undertaking was provided by recent reports (Hilton et al., 1986; Stinson, 1986) suggesting that the strong tumoricidal activity with high therapeutic—toxic index of FMA was related to its ability for the spontaneous generation of superoxide anion (02-) and hydroxyl (OH) radicals. For example, the suggested mechanism for the formation of 02- by FMA was (Hilton et al., 1986)FMA-OH + O2 FMA-O + H+ + 02-Here FMA—OH is simply the FMA molecule emphasizing the —OH moiety which becomes FMA-O, the free radical rep¬resenting the oxidized form of the drug. While some other highly effective anticancer drugs in current clinical application, such as bleomycin, are also thought to exert their antitumor effects via the formation of reactive drug-based or oxygenated free radicals (Carmichael et al., 1985; Gianni et al., 1983), FMA was considered unique in that only in this case the free radical formation was thought to be spontaneous, rather than through a metal- or an enzyme-activated process (Hilton et al., 1986; Stinson, 1986). Thus it was suggested (Hilton et al., 1986; Stinson, 1986) that FMA could be the forerunner of a new class of anticancer drugs. However, we noted that while the hypothesis seemed plausible, the reported ESR spectral evidence appeared to be ambiguous. Because of the high significance of the earlier conclusions (Stinson, 1986), we undertook a systematic ESR study of the radical formation in FMA solutions, and as discussed below, our conclusions disagree with those reported earlier."

Jan 1, 1989

Wires leading to or from underground facilities can develop hazardous voltages because of lightning exposure. The locations of many mine portals are particularly susceptible to lightning effects. The application of protective devices to limit this potential danger is necessary.

Jan 1, 1975

By Ralph L. Brown

The chemical properties of the unsaturated members of the aliphatic series of hydrocarbons are such as to render them " made to order" starting points or basic . materials for the synthesis of hundreds of important organic chemicals . The tremendous quantities of these unsaturated compounds that are being produced daily in the various coal carbonization and oil refining processes , and which at present have little value other than that of fuel , render a survey of the identity and ex- tent of occurrence of these compounds important from the viewpoint of economic utilization and resource conservation The increased need of liquid fuel and the relatively early exhaustion of petroleum resources will eventually require every utilization of liquid fuel products obtainable directly or indirectly from coal . Accordingly , the Bureau of Mines took advantage of an opportunity for examining the gaseous unsaturated hydrocarbons found in the gas obtained when a mixture of water- Collection of the material gas tar and coal is distilled in a gas-making retort . for examination was made possible through the courtesy of the Trent Process Corporation , Washington , D.C. , which was at that time carrying on at the Georgetown Gas Works , distillation of " amal gams " prepared from various coals and oils by the Trent process for cleaning coals . Kanawha gas coal ( 70%) and water gas tar ( 30 % ) from the Washington Gas Light plant were used in the " amal gam" being distilled at that time . The results obtained in this examination are presented here .

Feb 2, 1922

By Raymond B. Ladoo

The uses of talc are many but are not, in general well known or fully developed within the last decade several companies have realized the possibilities of greatly increased use and have intelligently proceeded to develop some of the fields which seemed most promising. This has had a tendency to lift talc from the obscurity in which it had existed for years, but the work is only started and much remains to be done. Considerably more attention has been paid to the technology and utilization of talc in Germany and Austria than in this country, despite the fact that the United States produces 65 of the world's talc and Germany and Austria combined but 5.4%. In the "Bericht,uber die tatigkeit des verbends der talcum-interessenten in Oesterreich-Ungarn" (Proceedings of the Austro-Hungarian Talc Association), for the years 1912 and 1913, many notes upon new uses appeared, together with suggestions as to further development of old uses. Aside from a few notes on the use of tar in paper, little has been published in the English language upon this subject. By recent action of the Talc and Soapstone Producers Association (U.S.A.) funds for research into the properties and uses of talc have been made Available and it is hoped that markets will be materially broadened a a result of this work.

May 1, 1920

By J. B. Janus

This report continues a series of analyses of coal samples made by the Bureau of Mines in connection with the yearly purchase of several million tons of coal for various Government agencies. Listed are the analytical data on the composition and quality of tipple and de livered samples of coal collected during fiscal year 1974.

Jan 1, 1975

By Wesley A. Grosh

The Allah Cooper mine, in Louisa County, Va., formerly was a producer of lead and zinc. It was believed that the critical shortage of leach and zinc and the fact that some ore had been produced at this mine justified exploration of it. A preliminary examination was made on April 30, 1943, by J. E. Hill, a Bureau of Mines Engineer. Diamond drilling was done on the property from November 30 to December 18, 1943, to determine whether the sulfide body extended to depth. One hole drilled to a depth of 650 feet and located so as to cut the Allah Cooper ore shoot about 150 feet below the lowest known mine workings failed to disclose sulfide vein at that depth.

Jan 1, 1949