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By NIOSH Publications

In 2004, 14,478 mining operations reported employment statistics to the Mine Safety and Health Administration (MSHA). Almost half (48.9%) were sand and gravel mines, followed by stone mines (30.4%), coal mines (13.9%), nonmetal mines (5.1%), and metal mines (1.7%).

Sep 1, 2007

In 2005, a total of 4,490 stone mining operations reported employment to the Mine Safety and Health Administration (MSHA). Stone mines comprised 30.6% of all mining operations. ? Mines producing the primary commodity of limestone (crushed and broken) comprised the largest number of operations (n=2,039; 45.4%). ? Stone mining operations were located in all states and territories except Delaware and North Dakota. ? Of all states, Pennsylvania had the most stone mines (n=379; 8.4%).

Jan 1, 2008

By Glenn C. Reed

This report is one of a series describing investigations within the Missouri River Basin in Montana made by mining engineers of the Bureau of Mines Minerals Division, Region II. The primary purpose of these investigations is to provide information to agencies of the Department of the Interior and and others concerned with the planning of Federal power developments in the basin. The report contains such factual data as have been authorized for public distribution. The field investigations in Broadwater County were made during the late fall of 1948 and the summer of 1949. Virtually all known metallic mineral deposits and some nonmetallic mineral deposits within the county were investigated. However, some long inactive mines and prospects on which little or no information is of record may have been omitted inadvertently. Many of the mines and prospects have been inactive for extended periods. Most of the underground workings now are inaccessible. Because of such conditions, impressions gained by the inspection of surface features have been supplemented necessarily, where possible, by information obtained from Federal and State publications.

Jan 1, 1951

By T. Ruff

Researchers at the National Institute for Occupational Safety and Health, Spokane Research Laboratory, studied technology and methods that could reduce accidents involving surface mining equipment that collides with other vehicles or workers, or drives over an unseen road edge. These accidents are partially attributed to the lack of full visibility around these large pieces of equipment. Blind areas can be extensive and this report presents plots of blind areas for five pieces of surface mining equipment. Several technologies designed for detecting obstacles in blind areas and providing a warning to the operator were evaluated on off-highway dump trucks. These proximity warning systems included radar, sonar, GPS, radio transceiver tags, and combinations of radar and cameras. A summary of test results is presented in this report, along with guidance on effective proximity warning technology, installation and maintenance considerations, and recommendations for effective implementation. This study found several commercially available systems that could effectively warn an equipment operator of an impending collision. Several new technologies also show promise for reducing these accidents. In most applications, it is recommended that sensor-based systems be combined with video cameras to provide important alarming functions along with an actual view of the blind area.

Jan 6, 2007

By Donald E. Redmon

This Bureau of Mines report reviews injury experience in the nonmetallic mineral industries (except stone and coal) for 1968-69. For each of the years, 23 tables summarize disabling work injuries by department, source of injury, extent of disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

Data obtained from the Mine Safety and Health Administration (MSHA) indicated a total of 889 underground (6.0%) and 13,982 surface (94.0%) mining operations.1

Aug 1, 2009

By J. M. Singer

Quenching distances for flames of methane-coal dust mixtures were determined with air and oxygen-enriched air. Coals used were Pittsburgh, Sewell, and Pocahontas No.3. Quenching distances were greater for flames of hybrid mixtures of coal dust and methane than for methane flames of corresponding stoichiometry. From the data of quenching distances and methane-coal dust concentrations was calculated the quenching equivalence, which is the increase in coal dust concentration required to maintain a given quenching distance value as the methane concentration decreases. These equivalences could be useful in identifying hazardous methane-coal dust mixtures in mines.

Jan 1, 1966

By J. H. Holden

The Federal Bureau of Mines is doing research and development work on a pressure-gasification pilot plant for producing synthesis gas directly from pulverized coal, oxygen, and steam. A pressure-gasification pilot plant has been constructed, and an investigation was made with the following basic objectives: 1. Determining the effect of varying pressure (75, 100, 150, and 300 p.s.i.g.), coal rate (400, 700, and 1,000 pounds per hour), and oxygen-to-coal ratio (8 to 11 std, c,f. per pound), on percentage of carbon gasified, oxygen and coal requirements per unit of CO + H2 produced, exit-gas temperature, and heat loss. The steam-to-coal ratio was maintained at approximately 0.3 pound per pound. 2. Development of a stabilized gasification zone or reaction space. 3. Improvement in operability of the pilot plant.

Jan 1, 1960

An independent contractor is defined by the Mine Safety and Health Administration (MSHA) as ?any person, partnership, corporation, subsidiary of a corporation, firm, association or other organization that contracts to perform services or construction at a mine.? Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Aug 1, 2009

An independent contractor is defined by the Mine Safety and Health Administration (MSHA) as ?any person, partnership, corporation, subsidiary of a corporation, firm, association or other organization that contracts to perform services or construction at a mine.? Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines. Companies In 2007, a total of 2,999 contracting companies reported employment at coal mines to MSHA, or 35.7% of all independent contracting companies.

Aug 1, 2009

In 2007, a total of 278 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 Metal mines were the smallest mining commodity sector, comprising 1.9% of all mining operations. ? Gold mines comprised 44.6% (n=124) of all metal mining operations. Other common types of metal mines were iron ore (n=36; 12.9%) and copper ore (n=35; 12.6%). ? Nevada had the largest number of metal mines (n=45; 16.2%), followed by Alaska (n=28; 10.1%).

Aug 1, 2009

By S. J. Pearce

One phase of the work of the Bureau of Mines in health and safety is promotion of the use of safe, satisfactory, and reliable respiratory-protective devices. To insure that such devices will be available, the Bureau has established schedules of minimum requirements for self-contained breathing apparatus,3/ gas masks,4/ supplied-air respirators (hose masks, air-line respirators, and abrasive-blasting helmets, hoods, or masks),5/ dispersoid (dust, fume, and mist) respirators,6/ and nonemergency gas respirators (chemical-cartridge respirators).7/ Approval tests of self-contained breathing apparatus are conducted under the supervision of mining engineers of the Accident Prevention and Health Division} Region VIII; approval tests of other types of respiratory-protective devices are conducted by the Health Branch.

Jan 1, 1952

By Martin Berman

Tables of 28 positions for all the transitions for nine common analyzing crystals for first, second, and third order reflections were compiled by the Bureau of Mines to facilitate elemental X-ray fluorescence analysis on multi-element systems. The tables are based on a compatible set of wavelengths for 2,346 observed X-ray transitions of the elements lithium to americium. The results are tabulated in order of increasing wavelength as well as by increasing wavelength for each element.

Jan 1, 1969

By J. E. Shelton

Flotation tests are described on samples of two lowgrade nickeliferous ores of Oregon and Washington. The sample from the Congress mine, Ferry County, Wash., contained 1.2 percent Ni, occurring chiefly as millerite. The sample from the Shamrock mine, Jackson County, Oreg., contained 2.20 percent Ni and 0.78 percent Cu occurring chiefly as pentlandite, nickeliferous pyrrhotite, and chalcopyrite. The millerite in the Congress ore was concentrated by flotatioin with aulfydric collectors in a series of locked tests to recover 73 percent of the nickel as a 7 percent bulk concentrate. By successively regrinding and floating the bulk concentrate, it was further concentrated to 12.4 percent Ni at a recovery of 59 percent and 21.8 percent Ni at a recovery of 50 percent. Attempts at selective concentration of the copper-nickel Shamrock ore were only partly successful because of the intimate association of pentlandite and chalcopyrite. The nickel concentrate, which contained 86 percent of the nickel, had an analysis of 4.42 percent Ni and 1.03 percent Cu. The copper concentrate had an analysis of 18.8 percent Cu and 1.96 percent Ni and contained 48.5 percent of the copper. A bulk sulfide concentrate contained 92 percent of the copper and 01 per¬cent of the nickel and had an analysis of 4.17 percent Ni and 1.63 percent Cu.

Jan 1, 1956

By V. R. Miller

The Bureau of Mines investigated methods for testing the tensile and sheer strength of cast specimens of bulk solder and of soldered joints in order to increase the strength and extend the useful temperature range of soft solders. A spread-area test for determining the wettability of solder on copper surfaces was developed. Mannitol was used as a flux in spread tests to control spreading and to avoid plating, etching, and other side effects of regular fluxes. Data on commercial and high-purity solders obtained by these methods show more consistency than those reported by others from similar tests.

Jan 1, 1967

By Irving Hartmann, John Nagy

"The pressures produced by dust explosions are frequently so great and are developed so rapidly that widespread destruction of manufacturing equipment and buildings results. Experimental data on maximum pressures and rates of pressure rise produced in a closed vessel by numerous metal powders and by dusts used in the plastics industry were published in two previous Bureau of Mines papers.4/5/One means for reducing structural damage is provision in the enclosing walls and/or roof of rapidly opening explosion-relieving devices or relief vents through which the pressure of an incipient dust explosion can be quickly dissipated. The vents can be simply unrestricted or free openings: hinged or pivoted sash which swing outward at a predetermined internal pressure; fixed sash, with light wall anchorages; scored glass panes; light wall panels; monitors or skylights; poppet-type vent closures; paper, metal foil, or other diaphragms that burst at low pressures; pull-out diaphragms, or other similar arrangements.The use of pressure-relief vents is recommended in the dust-explosion codes of the rational Fire Protection Association,6/ and recently a special committee on explosion venting has been organized. However, technical data on which the design and distribution of relief vents can be based are meager. An experimental study on venting grain-dust and cornstarch explosions was made by the Bureau of Chemistry and Soils, United States Department of Agriculture.7/ Tests on cork fines, cinnamon, starch, barley dust, and a phenolic plastic were made in a laboratory-scale (0.1-cubic-foot) apparatus by the engineering department of the Factory Insurance Association.8/ A study on the venting of explosions of acetone-air mixtures was made by the Bureau of Mines.9/The object of the present investigation is to extend the limited knowledge on the effectiveness of pressure-relief vents of different types, shapes, and sizes. The aim is to determine the venting requirements in equipment and structures of various dimensions and shapes for dusts of widely different explosive properties. On the basis of such accumulated information, together with theoretical considerations, it is hoped that ultimately it will be possible to recommend correct venting for most operations in which a dust-explosion hazard exists."

May 1, 1946

By H. E. Heide

The serious shortage of domestically produced asbestos during the war prompted the Bureau of Mines to investigate reported asbestos deposits in Alaska. The most promising' appeared to be these in the Cosmos Hills and Jade Hills areas along the Kobuk River in northwestern Alaska. The deposits along the west side of Shungnak River, a tributary of the Kobuk River, were the first to be investigated by the Bureau, in the summer of 1944. Four bulldozer trenches were excavated, from Which a 2-ton sample was taken. This sample was shipped to Rolla, Mo., for testing in the Bureau of Mines laboratory. In the summer of 1945 an investigation of asbestos deposits on Cosmos Creek, also a tributary of the Kobuk River, was begun; the work was completed during the field season of 1946.

Jan 1, 1949

By Robert C. Bates

This Bureau of Mines report converts published data on the cost of ventilating uranium mines to a common price base and analyzes these data to determine the cost per ton of uranium ore at various levels of radiation exposure control. There appears to be an exponential increase of cost as the radiation level is lowered. The 1967 base costs are extrapolated to present dollars, and some cost comparisons are given for other radiation control measures.

Jan 1, 1981

By A. T. Coumbe

The first national survey covering sales of fuel oil by States and principal uses was made in 1926 by E. B. Swanson of the Bureau of Mines (then under the U. S. Department of Commerce) under a cooperative agreement with the American Petroleum Institute. This annual study, covering the market for fuel oil, was made through 1930 with the financial help of the institute bat has since been continued by the Bureau up to the present time. The scope and coverage of the survey have gradually changed over the years as new uses for fuel oil have been found and new products have come into importance resulting in market expansion. Range oil (No. 1 fuel oil or kerosine) came into use for cooking and space-heating daring the depression era in New England, and it was first reported as a total in the 1931 survey. In 1934 the sales were compiled on a State basis. State totals for distillate fuel oil, Diesel fuel, and residual fuel-oil sales were first shown for 1934 and by principal uses and States in 1937. Kerosine deliveries by States and main uses were also released for the first time in 1937.

Jan 1, 1952

By W. D. Dietzman

In view of the developments and recent interest in recovering heavy oil, this report was prepared to present general information on more than 2,000 heavy oil reservoirs in more than 1,500 fields in 26 states. Information given on each heavy-oil deposit includes the following items: Field and formation, location, average or range of depth, average API gravity of oil, aver- age thickness of formation, areal extent of field, total productive wells drilled in field, discovery date of field, field status in 1963, cumulative production to Jan. 1, 1964, and all known types of secondary-recovery operations initiated (active and terminated) in the reservoirs. The geographical location of heavy oil accumulations in the United States is shown by a map, and a brief discussion of 14 different areas is given in the text. As of Jan. 1, 1964, 75 percent of the heavy oil reservoirs in the United States had produced more than 10 billion barrels of oil and are estimated to contain over 90 billion barrels of oil in place. It is also estimated that if the deposits which have had little or no production history, such as the one in Missouri, were included, the total remaining heavy oil in place would be in excess of 150 billion barrels. To find economical ways of recovering this vast reserve of heavy oil, industry is developing technology in several types of thermal-recovery methods. Some of the general considerations and more suitable limitations in selecting a prospect to study fur thermal-recovery techniques are: Lithology, depth, viscosity of reservoir fluids, gravity of oil, reservoir thickness, oil in place, and permeability and porosity.

Jan 1, 1965