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By Arthur L. Murray

"Putting safety over , " using the accepted meaning of the word " Safety " as the elimination of personal injury , resolves itself into the prevention or disassociation of a combination of two distinct circumstances . Opportunity for accidents is afforded by conditions that are likely to cause injuries , but such injuries are effected only when the human body is placed in a position to be injured . As will be discussed later , in mining , as in most other industries , the degree of safety experienced depends upon the disassociation of these two circumstances , first , by making working conditions as free from hazards as possible , thus affording the minimum opportunity for accidents to occur , and secondly , the training of employees to recognize dangerous conditions and adopt measures to protect themselves and their fellow employees against injury . The responsibility for preventing accidents rests upon every person employed in an industry from the directing head down through the individual workers , and the safety of that industry will be proportionate to the extent that each member appreciates and accepts his individual responsibility . Hence , safety becomes decidedly a personal equation . Whether the personal equation will be so applied as to result in the greatest freedom from accidents , however , depends largely upon the initiative of those directing the industry . Putting safety over in a small mine presents the personal equation in a more intensified manner than the same endeavor in a large mine . Large mines , owing to their size and financial standing, can usually main ta in and support an effective safety organization with one or more directors who devote all their time to the supervision of safety work . Most small mines with a limited number of employees and limited capital can not afford and are not justified in supporting a paid safety organization , and must depend upon the close cooperation of their working force in maintaining safe working conditions . On the other hand , if proper supervision is exercised the small mine has in some respects advantages not afforded by the large mine . The limited workings in a small mine should afford less opportunities for dangerous conditions to arise and permits more frequent inspection of the entire mine . The small working force permits more latitude in the selection of employees known or believed to be either safe workers or amenable to safety educational work. Likewise , a small working force facilitates the carrying on of safety educational work and allows a closer personal contact between the superintendent and his employees .

Mar 1, 1923

Lower costs associated with hands-on training in donning and using a CSE ,self-contained self-rescuer (SCSR). Background In June 1987, the Mine Safety and Heath Administration (MSHA) issued an Emergency Temporary Standard (ETS) requiring that all persons entering underground coal mines must be given bands-on SCSR training. The ETS will shortly be replaced by a new standard requiring this hands-on training. Bureau of Mines research has shown that the most effective means of delivering this training is to have the trainee go through a six-step training procedure while in a kneeling position. Once the miner has looped the neckstrap over his or her head, he or she completes the donning sequence in this order: 1) activate oxygen; 2) insert mouthpiece; 3) put on nose clips; 4) put on goggles; 5) adjust neck and waist straps; and 6) replace miner's cap and prepare to move out. This procedure is repeated until the miner demonstrates that he or she is proficient at the task.

Jan 1, 1988

By J. W. Horne

The quantitative determination of salt in petroleum ins generally divided into two steps - (1) extraction of salt from the oil and (2) accurate measurement of the extracted salt. This paper presents a method used by the Bureau of Mines for quantitatively extracting the water-soluble chloride salts4/ from petroleum and discusses important details attendant on the success of the method. Among these details are homogeneity in the dispersion of salt crystals, emulsified brine and other impurities in the oil sample, complete solution of the salt, and total extraction and titration of all the aqueous phase. Recently, the chlorides of sodium, calcium, and. magnesium produced with and present in various oils have developed growing problems of salt deposition and corrosion in the petroleum industry. Therefore, a technical study of various emulsions and salts that accompany petroleum is being made by the Bureau of Mines in cooperation with the State of Oklahoma. One report (5)5 reviewing the literature pertinent to the study has been published.

Jan 1, 1940

By J. W. Horne

The quantitative determination of salt in petroleum ins generally divided into two steps - (1) extraction of salt from the oil and (2) accurate measurement of the extracted salt. This paper presents a method used by the Bureau of Mines for quantitatively extracting the water-soluble chloride salts4/ from petroleum and discusses important details attendant on the success of the method. Among these details are homogeneity in the dispersion of salt crystals, emulsified brine and other impurities in the oil sample, complete solution of the salt, and total extraction and titration of all the aqueous phase. Recently, the chlorides of sodium, calcium, and. magnesium produced with and present in various oils have developed growing problems of salt deposition and corrosion in the petroleum industry. Therefore, a technical study of various emulsions and salts that accompany petroleum is being made by the Bureau of Mines in cooperation with the State of Oklahoma. One report (5)5 reviewing the literature pertinent to the study has been published.

Jan 1, 1940

By David A. Benjamin

The USBM (U.S. Bureau of Mines) studied mines, prospects, and mineralized sites in the Roberts WSA (Wilderness Study Area) in 1984. The 15,090-acre WSA, located 35 miles northwest of Eureka, NV, is underlain by alluvial deposits of Quaternary age, extrusive and intrusive volcanic rocks of Oligocene through Miocene age, and metasedimentary rocks of Cambrian through Permian age. The Roberts Mountain Thrust fault cuts through the WSA, dividing the metasedimentary rocks into upper and lower plate rock units. One mine, the Kelley, which produced 397 tons of lead-zinc ore prior to 1940, and two prospects are within the WSA; no resources were identified. Exploration for precious metal deposits is presently being conducted in and adjacent to the WSA on large claim blocks. The study area contains six sites in and near these claim blocks that have anomalous gold and silver. Detailed exploration is needed to delineate resources. High purity silica rocks are present in the WSA. Barite, phosphate, oil shale, and vanadium occurrences just outside the WSA may extend into it, but no such occurrences were observed during the USBM study.

Jan 1, 1986

By A. B. Hooker

All State mining laws require that flame safety lamps be used in gassy mines; the laws of some States require that safety lamps be kept for emergencies at every coal mine, whether gassy or nongassy. The use of the flame safety lamp has been widespread because it is the only defice readily available for detecting both the presence of methane and deficiency of oxygen. This paper reports the results of an investigation by the Electrical Section, in cooperation with the Gas Section, of the Pittsburgh Experiment Sta¬tion relative to the behavior of permissible flame safety lamps in mine atmospheres deficient in oxygen and the effects of methane5 on the detection of Oxygen deficiency.

Jan 1, 1937

By W. W. Adams

"The present world-wide demand for increased production in all branches of essential industry involves a matter of vital concern t persons engaged in the mining industry, namely, the productive capacity of the individual mine employee. This applies particularly to coal-mining, upon which other industries so largely depend.The folded and faulted condition of the coal beds in some countries, as well as the thinness and depth of the seams, the adaptability to the beds of available mining machines and equipment are factors which cannot be overlooked in determining what increase in individual output may be looked for in any given country. This subject, while of fundamental importance, can only be referred to in a paper of this length, the primary object here being merely to present a comparative tatamant of individual output under prevailing conditions.The quantity of coal produced by a miner does not accurately indicate the miner's capacity as a workman, not only because of the natural conditions referred to above that limit his annual output, but also because of human factors which may possibly, however, be controlled, such as the demand for coal, the car supply, use of labor-saving machinery, number of days worked during the year, accidents in the mine, etc. It will, however, be an aid in answering the important question as to how and where the immediate need for coal throughout the world may best be surlier, if we examine the output of the miners in the important coal-producing countries over a period of years.Complete official information for recent years is, for several countries, jacking, particularly for France, Austria, and Prussia, but partial data from unofficial sources may be used to show the individual output of the miners in these countries."

Jul 1, 1920

By L. L. Oden

The purpose of this research was to develop a method to remove copper and tin from the magnetic fraction of incinerated municipal refuse, as recovered by the Bureau of Mines pilot plant in College Park, Md. Copper, present in the scrap in a metallic form bonded to ferrous objects, was amenable to leaching in cupric ammonium carbonate solution. Copper levels in small 5-to 10-lb lots of treated scrap were reduced from the initial level, 0.5 to 0.6 pct, to 0.1 to 0.2 pct. Larger lots of scrap (100 lb) were treated less effectively because of poor contact of solution and scrap. Oxidation in the air or in aerated aqueous solution was applied to liberate tin from the dilute solid solution present on the surface of incinerated tinplate. Shredding of air-oxidized scrap or caustic leaching of scrap oxidized in solution reduced tin levels from the initial 0.25-pct level to about 0.1 pct.

Jan 1, 1973

By T. C. Higgins, J. S. Malesky, J. A. O'Connor

"INTRODUCTION This circular contains the story of a stubborn mine fire of electrical origin that started on the main haulage road of No. 59 mine of the Peabody Coal Co. and illustrates that sometimes serious fires can be fought by direct attack. The story also points out that the cost of such procedure can be extremely high, and it is better, therefore, to minimize the possibility of a fire of electrical origin by suitable over-current and line-fault protection. The lives of 163 men were saved by utilizing a recently sunk air shaft near active workings as an escapeway. These men could not have reached the older openings. Also described are the rescue of 75 additional men through another air shaft, sealing of the fire, attempted extin¬guishment with carbon dioxide, and the difficulties of fighting the fire and recovering the mine.A fire occurred shortly before 12 o'clock noon, August 15, 1949, in the No. 59 mine, Peabody Coal Co., Springfield, Ill. All 257 men underground escaped to the surface. One group of 75 men was delayed from escaping for several hours after the alarm was given because smoke and fire gases were circulating in a main return airway, which intervened between their working section and one air shaft, and also in the stairway compartment of the shaft. After being supplied with universal-type gas masks, or self-rescuers, these men were conducted from the mine by members of a State mine-rescue team and other mine employees. Six nine officials were hospitalized because of exposure to carbon monoxide during fire-fighting activities; all were discharged a few days afterward. Later, while doing work incident to fighting the fire, two men were killed, and several were injured by falls of roof and rib.The fire broke out after a collision of a loaded trip with four empty mine cars on the main east haulage entry. The mine cars were jammed against the trolley wire causing a sustained electric arc that ignited the wooden mine cars and the fire spread to the timbers and coal."

Apr 1, 1950

By S. H. Katz, J. J. Bloomfield

Fires in zinc dust have sometimes given particular trouble owing to their resistance to extinguishers and the liability of explosions . Similar problems , notably with aluminum dust* , have previously been subjects of investigation by the Bureau of Mines .

Mar 1, 1922

By H. J. Heinen

This report summarizes preliminary research studies by the Bureau of Mines in electrowinning molybdenum directly from pure or impure molybdenum trioxide (MoO3) by fused-bath electrolysis in an open graphite cell without need of a protective inert atmosphere. A formulated electrolyte of the tertiary system containing 41.6 percent sodium pyrophosphate, 16.7 percent sodium tetraborat, 33.3 percent sodium chloride, and 8,4 percent molybdenum trioxide, by weight, electrolyzed at 1,000° C,, gave excellent results. Current density studies were made over a range from 20 to 260 amperes per square decimeter. Current efficiencies of 80 to 90 percent were obtained over the entire range. Yields up to 500 grams of molybdenum per kilowatt-hour were obtained. Higher current densities, however, reduced yields and produced a finer grained metal. The two most important facets in electrowinning molybdenum from MoO3, in an open cell, are temperature and electrode spacing to minimize or eliminate the formation of the suboxide MoO2, the major source of oxygen contamination. At temperatures of 1,000° C. and higher, together with the proper spacing of the electrodes, formation of oxides are practically eliminated. Molybdenum metal electrowon from pure MoO3 was 99.9 percent pure and contained 0,056 percent oxygen and 0,007 percent carbon. This metal, when arc-melted, had a Vickers hardness number of 175 and contained 50 parts per million oxygen and less than 10 parts per million carbon. Molybdenum metal electrowon directly from an impure MoO3 containing 90 percent MoO3 resulted in a metal of 99.8 percent purity.

Jan 1, 1961

By Robert L. Virta

The Bureau of Mines examined a fibrous talc sample from the Gouverneur talc district in New York by transmission electron microscopy (TEM) and polarized light microscopy to determine the mineralogical relationship of the fibrous talc to the amphiboles present in the sample. Two am-phiboles, anthophyllite and tremolite, were present in the sample. Tremolite occurred as a separate mineral phase, which was blocky in habit. Only a few composite tremolite-talc grains were observed. An-thophyllite, however, was present only in the fibrous talc grains. Mi-crodiffraction study of the fibrous talc grains containing anthophyllite showed that the anthophyllite was intermixed with the talc on a fine scale and that there was a crystallographic relationship between the talc and anthophyllite lattices in the fibrous talc grains. A mechanism similar to the process that forms biopyriboles could explain the structural defects, the fibrous habit of the talc, and the structural relationship between the talc and anthophyllite in the fibrous talc grains. Because of these characteristics, phase contrast microscopy and a provisional TEM technique for monitoring asbestos exposure would not distinguish between fibrous talc and fibrous amphiboles. TEM techniques employing electron diffraction and energy-dispersive X-ray analysis are recommended to positively identify the fibrous phases for regulatory purposes.

Jan 1, 1985

By E. G. King

Sodium-aluminum and calcium-aluminum silicates are important rock-forming minerals. While many of them are of only theoretical interest, several are of practical importance--as ceramic raw materials and as potential future sources of aluminum. Heretofore, thermodynamic data for these minerals were incomplete; and in many instances missing data were difficult to estimate reliably. This has seriously hampered thermodynamic calculations pertaining both to the natural formations of these minerals and to their decomposition in sintering and fluxing reactions. This paper reports the results of the Federal Bureau of Mines measurements of low-temperature heat capacities of four crystalline silicate minerals--dehydrated analcite (NaAlSi2O6), hexagonal anorthite (CaA12 Si208), lawsonite (Ca2Al2Si2080?2H20), and leonhardite (Ca2Al4Si8C24?7H2O). It augments previous similar measurements of related minerals, which were summarized recently.4 The measured heat-capacity data were used to derive entropy values for the four minerals at 298.15° K. Some relations between these entropy values and those of other similar minerals were discussed. These relations illustrate the difficulty of estimating entropy values of tertiary (or higher) silicates.

Jan 1, 1961

By R. L. Grayson, T. Simonyi, R. A. Andrel

"The purpose or this paper is to disclose analytical, statistical, and observational results relating to mineralogy and trace elements in respirable dust samples collected from two different mines in West Virginia. Samples were taken from longwall panels, and the panels operated in different coal seams, one located in the northern part or the state and the other in the southern region. Mining conditions and equipment arrangements on the panels will be described along with dust control techniques used. Results from sample analyses are summarized with emphasis on relationships between mineralogy, trace elements and mineral particle size to worker locations. Correlations are made between micro x-ray diffraction and energy dispersive x-ray analyses for sample mineralogy.IntroductionThrough the work of many researchers worldwide, the health of coal miners in modern societies is now protected from harmful exposure to respirable coal mine dust. A vast amount of research culminated in the exposure-response model of Jacobsen, et al, (l) which has been used to establish the 2 mg/m3 exposure limit in the United States. According to the model exposure to respirable dust for 35 years at this level or less could prevent the occurrence of a clinically significant case of coal workers' pneumoconiosis (CWP) in a miner. The exposure limit, of course, must be adjusted whenever greather than five percent free silica exists in the respirable dust.The Jacobsen model was built around a mean mass concentration exposure, which generally showed the highest correlation with both incidence and progression of CWP. As Morgan, et al noted, however, the quantity of respirable dust inhaled is not the only significant factor. 2) They noted that although mass of respirable dust correlates highe.st with the incidence of CWP, it is not a causal factor. Admittedly, the insidious processes causing the disease occur at the lund cell-dust particle level."

Mar 1, 1989

By D. J. Bauer

A solvent-extraction system employing selective stripping of a pre loaded organic phase was investigated for recovering Sm203 from a light-group rare-earth mixture. The samarium concentrated in the organic phase, and a >99-pct-pure samarium oxide product was obtained at 76-pct recovery in a 20-stage operation using di(2-ethylhexyl) phosphoric acid (EHPA) as the organic phase. The stripping agent was a 1.5-pct hydrochloric acid solution containing 200 g NH4C1/1.

Jan 1, 1972

By Thaddeus B. Evans

This information circular is one of a series describing mining methods and costs, being published by the Bureau of Mines. The Sunbright mine of the Foote Mineral Co. at Sunbright, Va., is the southernmost underground limestone mine in the State. It is a comparatively recent operation, and a description of its rapid development to production stage may have particular interest for the limestone-mining industry. ACKNOWLEDGMENTS Acknowledgment is made to the executives of the Foote Mineral Company including F. B. Shay, vice president in charge of production, W. B. Towner, general production manager; and to the members of the company staff at Sunbright for their assistance in preparing this paper.

Jan 1, 1957

By Daniel C. Boteler

Data from 68 entrained-bed carbonization tests were treated statistically by the Bureau of Mines, and several useful relationships were developed among the major variables. Nine coals, ranging in rank from lignite A to high-volatile A bituminous, were carbonized in two entrained-bed carbonization pilot plants. The carbonizing reactors employed were vertically mounted cylinders, internally heated, refractory-lined, and 10 inches ID. The range of carbonization temperatures was from 825° to 1,600° F. Using a regression-analysis computer program, empirical equations were developed by which carbonization temperature, air-to-coal ratio, devolatilization of coal, char yield, and volatile matter content of product char may be predicted.

Jan 1, 1973

By E. Aamland

Preparation of high-purity magnesium-yttrium alloys by electroreduction of Y2O3 dissolved in a YF3-LiF bath and the subsequent deposition of yttrium in a molten magnesium cathode was investigated in laboratory-scale apparatus. Parameters such as temperature, current density, and electrolyte density were studied. Electrolysis was conducted in a specially designed MgO diaphragm cell at temperatures ranging from 780° to 970° C. Alloys containing up to 55 weight-percent yttrium were prepared at cathode current efficiencies of 21 to 60 percent. Cell design and operation are described, and some of the limiting conditions pertaining to the method are discussed.

Jan 1, 1973

Efficiently clear ice and frozen materials from ore-handling equipment. Approach Compressed air-propane torches that develop a high energy flame jet were used instead of ordinary propane torches. How it Works A high velocity high temperature stream of gases impinges on the ice and frozen materials to both melt and blast them away. This hot gas jet is at 3,000°F temperature and moving at 3,000 feet per second. In the photograph below, the jet is being used to clear frozen taconite from a grizzly. The functions of the compressed air-propane torch are as follows. The air heater assembly, which is mounted on a wand, con-

Jan 1, 1980

By E. J. Kloos

The Bureau of Mines devised a new machine-test method for measuring carbon dioxide inspired by a wearer of self-contained breathing apparatus. The new method compares favorably in speed and precision with standard man-tests in which the apparatus is tested while actually worn, and is scheduled for use in future approval tests for facepiece carbon dioxide 'measurements. However, man-tests will still be used to measure the efficiency of the carbon dioxide sorbent materials in closed-circuit breathing apparatus.

Jan 1, 1966