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By Stephen A. Swan

Bureau of Mines research has not included analyses of mining dredge safety since 1948. Because of the increasing use of dredges, 63 fatal accidents and several hundred nonfatal injury accidents involving dredges were examined. Also, 31 working dredges and 3 dredge manufacturers were visited to acquire qualitative information. Drowning accidents represented 59 pct of the fatalities and are delineated in detail. Also, countermeasures against other hazards are discussed.

Jan 1, 1985

By David C. Oyler, Herbert H. Fields, William P. Diamond

A 3-inch pilot hole was directionally drilled to intercept the Freeport coalbed horizon horizontally at Mather, Pa., as part of a Bureau of Mines degasification project. The original concept was to continue the horizontal drilling into the coalbed, after the initial intercept, with a total of three horizontal holes eventually being completed. However, the erratic thickness (0.0 to 4.3 feet) of the Freeport coalbed at Mather was not sufficient to sup- port the horizontal drilling degasification technique, and the site was abandoned after six attempts to locate adequate continuous coal thicknesses. The drilling of coreholes in the immediate vicinity of proposed well paths to evaluate coal thickness is essential prior to future slant hole operations. Although mechanical failures of the new directional drilling equipment, mud pump and rig breakdowns, directional control problems, and exploratory horizontal drilling in the Freeport horizon more than doubled the anticipated cost of the pilot hole, continuing improvements in directional drilling equipment and techniques should significantly reduce the time and costs of future drilling operations.

Jan 1, 1977

By D. H. Baker

This report, one of a series prepared by the Federal Bureau of Mines on the technology of titanium, describes the development of an electrorefining cell from which cathode deposits up to 30 inches long can be produced. Data show individual deposits to be homogeneous, comparable from top to bottom, and not varied in quantity or quality of metal over the entire length of the deposit. Investigations concerned with various diameter cathodes showed that cathode current efficiencies were materially reduced with cathodes less than 2 inches in diameter. Deposits produced on 1/2-inch-diameter cathodes showed cathode current efficiencies of 19 percent and on 1-inch cathodes, just over 22 percent, whereas deposits produced on 2- and 4-inch-diameter cathodes showed about 70-percent current efficiencies. A series of 20 deposits on 4-inch-diameter cathodes was produced under simulated production operation. The average current efficiency, based upon a divalent ion, was 72 percent with 11 1/2 pounds of metal produced per cycle of operation - 98.8 percent of which had a Brinell hardness number (B.h.n.) of 80 or less.

Jan 1, 1959

By Howard C. Turnage, Dana T. Updyke, Wayne C. Muhler

The objective of this project was to develop technical data and evaluate performance and utility of leaky feeder communications systems currently used in North American underground mines. The desired information was obtained principally through on-site surveys. Altogether, six of the seven mining companies known to be using leaky feeder communications were visited. This report covers the findings of these surveys. In addition, the report provides a brief background summary of mine communications, a technical discussion of leaky feeder systems, and conclusions and recommendations based on the results of the survey.

Jan 6, 1980

To reduce operator exposure to drilling noise from roof bolting machines. Background Noise-induced hearing loss (NIHL) is a prevalent occupational illness in the United States. Studies indicate that 70%?90% of miners have NIHL significant enough to be classified as a hearing disability. Mine Safety and Health Administration studies indicated that roof bolting machine operators are among those overexposed to noise. Field studies support the premise that, on average, drilling is the loudest noise source to which a roof bolting machine operator is typically exposed and contributes greatly to the operator?s noise exposure. The National Institute for Occupational Safety and Health (NIOSH) has further determined that the drill steel and chuck radiate a significant amount of noise during drilling. To address this noise hazard, NIOSH developed a collapsible drill steel enclosure (CDSE) to encapsulate the drill steel during the drilling portion of the roof bolting machine duty cycle. In addition, NIOSH is collaborating with J. H. Fletcher & Co. in the continued development of a CDSE.

Sep 1, 2008

By Joseph H. White

In its investigations looking to the improvement of health condi- tions and the increase of efficiency in the mining industry, the Bureau of Mines, in cooperation with the Bureau of Public Health, is studying sanitary conditions in and about mines with the intent of pointing out how those conditions that are a menace to the health of the miner may be most efficiently removed or remedied. An out- line of sanitary betterment work at mining villages in the Birming- ham district of Alabama has already been published by the bureau," and in this bulletin are presented suggestions on the planning of mining towns and the construction of miners' houses. The bulletin does not pretend to be a treatise on the so-called "housing problem," and mentions sociologic issues only incidentally. It is assumed that the influence of proper shelter on health is understood and that not a lack of appreciation so much as a lack of knowledge of the best remedies is responsible for many of the undesirable conditions that exist at mining towns. The purpose of this bulletin is to supply facts on the building of well-lighted, well- ventilated, warm, attractive, and economical houses for miners, these houses being assumed to be units of an industrial village or town the building and management of which are under the control of a corporation, so that special conditions hold which do not apply to houses built and owned by individual miners. From this it is not to be inferred that the company-controlled town is the best system or the only one in vogue. The discussion of this side of the subject in all its phases is too involved to be included in this paper. One element in favor of the company-controlled town is its possible immediate responsiveness. Hence this assumption. Also the assumption is made that a-new isolated town is being built, and hence the selection of the site, the arrangement of the streets, and the situation of the houses are discussed before the house itself is treated, for one of the most important factors in obtaining an economical sanitary house is a well-selected town site. Many of the suggestions, however, may be applied in improving conditions in existing towns, in building new houses in old towns, or in repairing old houses. Emphasis must be laid on the fact that as a rule a mining village has a shorter life than a manufacturing town. Economy is emphasized frequently because the discussion is predi- cated upon the assumption that the miner himself is to pay for all that he gets. House rent will doubtless be expected to bring in a reasonable return on all money invested in streets, sidewalks, water supply, sewer system, and houses; in other words, the town is to be run on a business and not on a paternal or charitable basis. "Fair and reasonable" precludes, of course, the idea of excessive returns. Some companies do not consider it good policy to realize as high a rate of interest as an independent realty company would be war- ranted in realizing. Under some circumstances part of the town improvements might be charged as "expense of the industry," that is, to the consumer. The isolation of a mining town introduces a unique responsibility. As the miners are practically obliged to rent the company houses, the officials of the company ought to scrutinize all expenditures in- volved so that house rent may be reduced to a minimum. In a way the town builders are placed in the position of trustees. They deter- mine, within certain limits, what proportion of a man's wages shall be spent on house rent. This consideration should restrain fanciful and unnecessarily expensive building; the other extreme should like- wise be avoided. True economy should be distinguished from cheap- ness. Ugly, insanitary, uncomfortable shacks should not be built even if, because of their cheapness, there is a demand for them from tenants. The obligation of the industry to society as a whole as well us to the tenant ought to forbid this. A cheerful, strong, healthy, virile race will not rise out of the filth and squalor of cheap hovels. An insanitary environment often does its damage slowly and silently; vitiated air does not, like mine gas, announce its deadly work by an explosion. As Talbot⚫ says: Health depends in part on freedom from infection. The probability of obtain- ing that freedom will be greatly increased by maintaining the body at a high state of vigor, or "vitality," as it is popularly called. This implies the promo- tion of all agencies which have to do with the physical well-being as well as with the control of sources of infection. Many men realize that in building houses for their workmen they are invested with a peculiar responsibility that must be wielded wisely, and in large developments they call into consultation the land- scape architect, the sanitary engineer, and the building architect, as well as the mining engineer.

Jan 1, 1914

By S. M. Shelton, W. A. Calhoun, M. M. Fine, T. L. Johnston

"This report is () expansive test program by the Bureau of Mines to determine methods from various and ferrous manganese-grade product () widespread () and manfniferrous iron ores. Among the samples received for testing was one from the pits of the Barytes Mining Co., 1-1/ 2 miles northeast of Cartersville, Ga.. The property is approximately in the center of the Cartersville manganese district and shares a common corner with properties of the New Riverside Ochre Co. and the Etowah Development Co., both producers of manganifereus ores. The deposit is typical of the district and occurs in residual clays resulting from weathering of the Shady limestone and Weisner quartzite. 7/The property is developed by a number of open pits ranging to 60 feet in depth. In 1918 several carloads of manganiferous iron ore was mined from an alit on the property. Since then mining operations have been negligible. The ore is known locally as calico ore.A 4-ton sample representing -re as it occurs in the -pen pits vas furnished for testing. The sample consisted of a mixture of red iron oxides, wad, and clay, with small pebbles of manganese oxides and siliceous fragments scattered throughout."

Mar 1, 1943

Researchers with the National Institute for Occupational Safety and Health (NIOSH) have developed a training module to educate both new, inexperienced miners as well as veterans on important issues related to self-rescue and escape procedures. These include: (1) physical and environmental conditions that can be encountered in a mine after a major explosion, (2) knowledge of emergency meeting locations and escape routes, (3) the importance of using self-rescuers, even in seemingly clear air, to keep the lungs isolated from contaminants, and (4) why miners should not go off to look for others who are missing. In addition, the module may stimulate miners to think about and discuss mine explosions and the devastating effects of such an event.

May 1, 2009

By Walter C. Lorenz

Samples of materials containing pyrite from various coal mines and coalbeds were studied to compare their compositions and oxidizing characteristics. Pyrite was the only form of iron sulfide identified, but X-ray diffraction, emission spectrography, and microscopic analyses revealed similar suites of minerals and trace elements. The pyrite occurred usually in spherical clusters of very small crystals. The oxidation of pyrite in solutions of PeSO4 and Fe2(SO4)3 and in the presence of an iron oxidizing bacterium Ferrobacillus ferrooxidans, was studied through a manometric technique. FeS04 or Fe2(SO4)3 solutions had no appreciable influence on pyrite oxidation under the test conditions, The bacterium acted as a catalyst, greatly increasing the oxidation rates; however, in three samples that also contained calcites, bacterial oxidation was greatly reduced. The oxidation rates also increased approximately as the percentage of pyrite in the samples increased. For the series of samples studied, there was no definite correlation of the results with the location of the various mines nor with the acidity of alkalinity of the mine drainage.

Jan 1, 1963

By Robert P. Vinson

The U.S. Bureau of Mines evaluated a light-scattering technique for discriminating between spherical and nonspherical particles. This evaluation was a three-step procedure. The first step required collecting light-scattering data for a variety of particles. This was accomplished with a particle analyzer called the DAWN-A. The DAWN-A measured the scattered light intensities of individual particles at a forward scattering angle of 40°. These DAWN-A measurements of individual particles are called scattering signatures by the Bureau researchers. The second step in this evaluation was to calculate a sphericity index number using the scattering signatures produced by the DAWN-A. The sphericity index number can range from 0 to 1. A calculated sphericity index of 1 would show that based on the intensity of scattered light, the particle was a perfect sphere. The third and final step of this evaluation was the comparison of the calculated sphericity indices of the various particles. Comparing these indices made it possible to discriminate between the nearly spherical waterdrops and the nonspherical coal and rock dust particles.

Jan 1, 1993

By E. P. Youngman

This paper is one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate-mines in various foreign countries. This interpretation of the mining laws of Greece was prepared from information furnished by Ralph B. Curren, American assistant commercial attache, Athens, in reply to a questionnaire of the United States Bureau of Mines, transmitted through the courtesy of the commercial laws division of the Bureau of Foreign and Domestic Commerce. INTRODUCTION In his report,3 Mr. Curren states that the source of his information was the Director of Mines of the Greek Ministry of National Economy and the Mining Code of Greece, which was, compiled from existing laws in 1929,4 and which has since been modified by several acts of Parliament.

Jan 1, 1932

By W. E. Lamont

The Bureau of Mines studied the potential for recovering marketable barite concentrates that meet oil well drilling-mud specifications from barite waste pond materials. The study was conducted as part of the Bureau's research program to conserve domestic mineral resources by advancing mineral recycling technology. The samples, which were obtained from Georgia, Nevada, Missouri, and Illinois, varied widely in character, particle size, and barite content. The samples were treated with sodium silicate and sodium cetyl-stearyl sulfate and then floated. The flotation flow sheet was modified to reject barren coarse and/or slime fractions from some of the samples, and one feed sample had to be scrubbed prior to flotation to remove residual flotation reagents. The cleaned concentrates had BaS04 contents ranging from 95.0 to 96.9 percent, while recovering 81.2 to 95.9 percent of the barite in the feed. The specific gravity of each concentrate exceeded the specification of 4.2. The removal of the flotation reagents from the flotation concentrate was not investigated.

Jan 1, 1982

"When a metal-mining company takes out a workmen's compensation insurance policy, it does so to relieve itself of its uncertain and variable financial liability under laps requiring payment to employees for lost-time accidents, there-by passing the liability or to the insuring agency. For this service, or rather for the assumption of the risk, the insuring agency charges the mining company a price, or in insurance parlance, ""a premium"".The insuring agency depends upon a volume and variety of business to average the losses incurred by its individual policy holders, and determines its price to cover losses that are suffered and its cost of doing business.It is generally known that all types of insurance are founded on the theory of probability applied to large groups of risks, Workmen's compensation insurance is no exception, and the average price paid therefor must be based on the frequency and severity of accidents in the particular industry or branch of industry under consideration. The frequency and severity rates are determined by statistics, which, of course, unless standardized, kept carefully and consistently, and analyzed properly, are liable to be inaccurate and misleadingThe importance of large groups in arriving at an average price for insurance service can not be overestimated, For example the writer knows of one small group of some twenty metal-mining companies whose losses during the past two years exceeded their premium charge by 54%. Not a single individual company during the two years kept its losses below the premium rate. For several years the group as a whole has persistently exceeded its premium rate, Such risks are not profitable to the insuring agencies and can only be carried where a large volume of good risks will balance the poor risks, but in order to conform to good insurance ethics the premium rate must be based on averages for the industry as a whole, and kept sufficiently low to induce operators to sell their risks."

May 1, 1924

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Jan 1, 1997

The head loss data for coal slurries over a range of concentrations and velocities and the laboratory screen analysis were selected as areas for investigation in the data analysis performed. The analysis resulted in the following: (1) Size distributions for the coal used in the horizontal pipeline tests were fitted to the Rosin - Rammler distribution function. Each of the fits was significant. Corresponding Rosin - Rammler parameters were obtained which were introduced into the regression analysis. (2) A regression equation was obtained which predicts the slurry head loss of 1-inch by 0 coal slurries ranging in volumetric concentration from 20 to 40 percent and line velocities from 1 to 14 feet per second as a function of the square of velocity. The addition of the term for concentration in the regression equation did not contribute significantly c head loss.

Jan 1, 1972

By Charles Vaught

This paper discusses the fact that US coal mining organisations are losing the knowledge they need in order to be able to respond to emergencies. The authors note that knowledge management provides a useful perspective from which to view the problem, but that the debate about what constitutes knowledge should be broadened to include a debate about what constitutes management. It is argued here that knowledge is actually shared knowing distributed across group members; that such knowledge can be managed by cultivating it; and that narrative is the medium through which this may be done. The paper then examines NIOSH research that has attempted to use such an alternative knowledge management approach to help potential mine emergency responders better deal with the predicaments they are likely to encounter on-site.

Jan 1, 2006

By John W. Frey

This paper presents one of a series of digests of foreign mining legis- lation and court decisions, which is being prepared in advance of a general re- port relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws governing the Portuguese overseas possessions, prepared from the best avail- able information in Washington, has been slightly amplified in accordance with suggestions transmitted through the courtesy of the Department of State by Fred Morris Dearing, American Minister at Lisbon.

Nov 1, 1929

By D. Harrington, B. W. Dyer

"One of the products of the activities of the United States Chemical Warfare Service is a simple device and method for nearly instantaneous determination of small quantities of carbon monoxide in air. Since the war, this device has been diverted to commercial uses, and is now being marketed in connection with rapid determination of the comparatively small but dangerous quantities of CO, which may be found in garages, in sewers, about blast furnaces, etc. Also, it probably has a definite field of use in both coal and metal mines in connection with fires and explosions, as well as in confined places after firing of explosives) the latter applica-tion being of especial importance in metal mining.The device as marketed is readily portable, being small and light enough to carry in a coat pocket of medium size. In operation, a sample of the air mixture is drawn into a small rubber bulb, then forced through a small glass tube filled with certain chemicals upon which CO has the effect of changing the original color from gray or white to shades of green, the deepness of the green determining the percentage of CO in the air. A color scale is attached for purpose of comparison and determination of CO percentage. Only a few minutes are consumed in obtaining the result, all work being done on the ground.The exact effect of minute quantities (up to 1/10 of 1 percent) of CO on the human system is somewhat uncertain, and much research has been and is being done to obtain definite data on this point. It is, however, definitely known that in air containing more than 1/10 of 1 percent CO men doing hard work are quickly and seriously affected. As the gas is tasteless, colorless and odorless, methods of determining the presence of both small and large quantities have been of much importance. Technical Paper 11 of the U. S. Bureau of Mines gives much data as to effect of CO on mice and canaries. It was found that mice show very little distress until the CO content is about 0.20 percent, but quickly succumb when that percentage is exceeded; canaries are somewhat more susceptible; they quickly show distress in as little as 0.15 percent 00, and soon collapse when that percentage is exceeded."

Jan 1, 1921

By Charles Vaught

This paper discusses the fact that US coal mining organisations are losing the knowledge they need in order to be able to respond to emergencies. The authors note that knowledge management provides a useful perspective from which to view the problem, but that the debate about what constitutes knowledge should be broadened to include a debate about what constitutes management. It is argued here that knowledge is actually shared knowing distributed across group members; that such knowledge can be managed by cultivating it; and that narrative is the medium through which this may be done. The paper then examines NIOSH research that has attempted to use such an alternative knowledge management approach to help potential mine emergency responders better deal with the predicaments they are likely to encounter on-site.

Jan 1, 2006

By H. H. Schrenk

There are several well-recognized procedures for controlling exposure to hazardous atmospheres in industry. They include (a) substitution of less toxic material, (b) enclosure of processes, (c) wet methods, (d) local exhaust, (e) general ventilation, and (f) use of respiratory protective devices. In addition to their employment as a control measure in occupational exposures, respiratory protective devices also are essential in emergencies that may arise from failure or improper use of other control equipment. Respiratory protective devices usually are employed to supplement other methods of control, as temporary expedients, or when other methods are not readily applicable or practicable. It seems reasonable to assume, however, that where respirators are used consideration has been given to the factors involved and that the devices can provide satisfactory protection if used properly. Their use should not be arrived at simply by a process of elimination of other methods that are more difficult to apply.

Jan 1, 1943