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In the three years to June 2005, 959 injuries associated with continuous miners (CMs), shuttle cars (SCs), load-haul-dump and personnel transport (PT) were reported by NSW underground coal mines, comprising 23% of all injuries reported. The present paper reports an analysis of the narrative field accompanying these reports to determine opportunities for controlling injury risks. The most common combinations of activity and mechanism were: strain while handling CM cable (96 injuries); caught between or struck by moving parts while bolting on a CM (86 injuries); strains while bolting on CM (54 injuries); and slipping off a CM during access, egress or other activity (60 injuries). For the other equipment considered, the common injury mechanism was the vehicle running over a pothole or other roadway abnormality causing the driver or passengers to be injured (169 injuries). Potential control measures include: monorails for CM services; hydraulic cable reefers; handrails on CM platforms; redesign of CM platforms and bolting rigs to reduce reach distances during drilling and bolting; improvements to guarding of bolting controls; standardisation and shape coding of bolting controls; two handed fast feed; improvements in underground roadway maintenance, vehicle suspension, visibility and seating; and pedestrian proximity warning devices.

By F. W. Hoertel

The effects of certain process variables on the grain size, grain type, and microhardness of vapor-deposited tungsten were established, and the near-optimum parameters and the efficacy for the vapor deposition process were determined. No significant change in the grain size or microstructure resulted from ultrasonic vibration of the substrate during deposition, from variations in the hydrogen (H2) to tungsten hexafluoride (WF6) ratio, or from small increases in reaction-chamber pressure. Near-optimum conditions were continuous deposition at atmospheric pressure, a deposition rate of 2-mils thickness/square inch of substrate area/hour, a temperature of 5500 C, and a hydrogen to WF6 ratio of 4:1. The addition, individually, of about 2 volume-percent of butane, 24 volume-percent of carbon dioxide, or 4 volume-percent of propane to the hydrogen and WF6 mixture produced deposits with the finest grain size for each gas. A corresponding increase in microhardness accompanied the decrease in grain size. The addition of gases did not alter the columnar microstructure found in vapor-deposited tungsten.

Jan 1, 1966

By Aarne Visnapuu

Pneumatic chipping, scaling, and grinding can expose the tool operator to noise levels in the range 90 to 120 dbA. In most chipping and scaling operations, casting resonance is the primary source of noise, followed by air exhaust, and machine and chisel resonance. In grinding, the air-exhaust noise predominates. The Bureau of Mines has shown that noise from these operations can be reduced by up to 15 dbA. Workpiece resonance was reduced by sand or other damping methods; tool resonance, by internal damping; and chisel resonance, by constrained-layer treatment. Mufflers reduced air-exhaust noise, and an acoustically treated booth was effective in containing noise around the work area without increasing operator exposure.

Jan 1, 1977

By Wing G. Agnew, John A. Johnson

"INTRODUCTION This paper is one of a series being published by the Bureau of Mines pertaining to an investigation on the use of stemming in metal mines now being conducted at the Mount Weather Testing Adit. Its purpose is to compare the amount of dust and gases produced as a result of blasting charges of dynamite (1) in drill holes, (2) in bombs, and (3) in mud-cap or adobe shots.ACKNOWLEDGMENTSValuable assistance and advice on stemming were given by members of the staff at the Bureau of Mines, as acknowledged in previous publications. 4/TEST PROCEDUREThe results used for comparison in this report are from dust and gas samples taken after blasting (1) four regular test rounds with no stemming, (2) five bomb shots, and (3) two mud-cap or adobe shots."

Dec 1, 1942

By R. T. Artz

Disposal of sewage is an important part of mine sanitation. Improper... handling and.disposing of sewagerare conducive to the spread of disease and often add foul and nauseating odors to the mine air. The diseases spread by unsafe methods of disposing of waste in mines are typhoid fever, cholera, amebic dysentery, hookworm, and other intestinal diseases due to parasites. Sanitary toilet facilities, with a good sewage-disposal system, each maintained in good order at all times, should help to prevent the spread of diseases transmitted by intestinal body wastos. The metal and nonmetal-mining industries have recognized the impor-dma tance and need for disposing sewage properly; accordingly, facilities of some sort are installed and need today in most large mines. The coal-mining industry has given little thought to the disposal of sewage underground; however, in most mines of the anthracite industry, the inflow of large vol- unes of highly acid mine water and the extensive drainage system required to remove this water provide a natural means for disposing of sewage.

Dec 1, 1946

By Gerald A. Munson, E. P. Barrett

Rapid and accurate estimation of the proportions of mineral in rock mix- tures is essential in mineral-dressing research and industrial operation. Estimation of the proportions of potash and soda feldspars in ground pegmatite material by casual observation is almost impossible and may be tedious or even difficult by petrographic examination. Chemical analysis may not be an accurate measure, as pegmatite rock may contain the following minerals:

Jul 1, 1947

By Julie Mitchell, Robert King, Len Eros

The Bureau of Mines has studied the Deserado Mine computerized monitoring and control system, located in Rangely, Colorado, to acquire knowledge about the overall costs and benefits of mine monitoring systems. The Deserado system is a complex system monitoring environmental parameters, electrical power, and operation of all mine equipment, and controlling the entire conveyor haul age system. This paper discusses the evaluation of the Deserado monitoring system from initial design through system installation and operation. It also examines the costs, benefits, and performance of the monitoring system.

By Jr. Oitto

A polyester-type resin and deformed-steel reinforcing bars (rebars) were used in to strengthen and to stabilize bolted, fractured wall rock along pas 1:'y. in a western gold mine. Reinforcing bars were placed in boreholes drilled into fractured rock and then were surrounded by resin pumped under pressure into the holes and intersecting fractures until the wall rock was thoroughly impregnated. Pumping and injection equipment and infusion procedures are described. Visual examinations for movement in bonded and adjacent unbonded rock were made for 3 years. Fractured walls containing resin-rebar installations were strengthened. The results suggest that resin-rebar support can be used advantageously and economically in repairing fractured or broken rock when compared with rock bolting or timbering.

Jan 1, 1965

By E. D. Gardner

"It has only been in recent years that the proper ventilation of metal mires has received serious consideration. Increasing temperature and humidity with greater depth in some of the larger mines of the West prevented the efficient operation of the mines and made the installation of mechanical ventilation systems necessary. Doors that interfere with tramming are generally needed to control properly the mechanically induced air currents and are one of the inherent disadvantages of the system. In fact the necessity for the use of doors in the main haulageways has discouraged the installation of mechanical ventilation in some metal mines.A number of mining companies in Arizona are using ventilation doors which can be opened and shut mechanically by the motorman without leaving his seat or stopping his train, end thus interfere very little with the transportation of the ore. The Copper Queen Branch of the Phelps-Dodge Corporation at Bisbee introduced these ventilation doors and adapted them from those in use in the company's coal mine at Dawson, New Mexico. Other mining companies have installed the same type of door and it is now being used in a number of districts in Arizona.The doors at the Calumet and Arizona mine in the Bisbee district are representative of those in use. The doors at this mine are substantially built of 2-inch lumber, are air tight, are well placed and have two openings or passageways. The main door, which is used for the motor trains, is 5 feet wide by 6 feet high and is opened by compressed air and closed by a counterweight. At the side of the motor door is the man door, which is 16 inches wide by 5 feet high and is opened and closed by hand."

Aug 1, 1921

By Travis Q. Lyday

The Other South Pacific Island states extend from Palau, also called Belau, near the Philippines in the west, to French Polynesia in the east. However, a number of countries and territories have been omitted, from this chapter because their mineral production was insignificant to the local economy. These include the French over-seas territories of French Polynesia and Wallis and Futuna Islands; independent states, including Kiribati, Marshall Islands, Micronesia, Palau, Tonga, Tuvalu, and Vanuatu; the New Zealand freely associated state of the Cook Islands, and the New Zealand dependency of Niue. What mineral production existed in these islands was limited to construction materials such as coral reef limestone, crushed stone, and sand and gravel in minor quantities solely for domestic consumption. FIJI The mineral industry of Fiji continued to be dominated by gold, although this sector contributed less than 1 % to the gross domestic product (GDP) of the country. Gold and silver together ranked second in value among the country's exports. Fiji's economy contracted 11% during the 8-month period following the first, on May 14, of two military coups. Although the island nation had been a member of the British Commonwealth of Nations since its independence on October 10, 1970, Fiji's membership terminated with the emergence of the Republic or Fiji on October 15.

Jan 1, 1989

By T. A. Henrie, D. C. Fleck, D. G. Kesterke

Uranium metal was electrowon from uranium dioxide dissolved in fluoride melts . The UO₂ was fed directly to the cell in a continuous manner . Electrolysis was performed at 1 , 200 ° to 1,300 ° C in electrolytes composed of UF4 , LiF , and BaFa . A single regulus of metal was collected in a confined area of the crucible . Product purity of 99.8 percent was attained . Carbon was the major contaminant . Compartmented cells were studied as a means of confining the oxide feed to the vicinity of the anodes .

Jan 1, 1964

By R. W. Van Dolah

The feasibility of formulating cap-sensitive slurry explosives for use in underground mines with potentially flammable gas atmospheres was examined. Formulations containing aluminum metal as sensitizer and sodium chloride to reduce incendivity were prepared; some were cap-sensitive and had adequate air-gap. Flaked aluminum metal rather than the atomized type proved to be the more effective sensitizing agent of the formulations tested for incendivity in the large gallery of the Bureau of Mines, some were found to be suitably nonincendive.

Jan 1, 1968

By L. C. IlsLey

The first thing to consider in prevention of electric shock is the voltage of the circuit. No person can be sure that he will not be killed, even from a 110-volt circuit, if he makes proper contact with the circuit so as to cause the maximum current to pass through his body. As the voltage is increased to 250 volts, 500 volts, or 2,300 volts the danger from contact with the electric circuit is increased, Alternating current of the same nominal voltage is possibly more dangerous than direct current. Experience has taught us that both will cause death, and that if the fatalities from this source are to be kept low, certain precautions in the guarding of circuits must be observed.

Feb 1, 1929

By Maria I. De Rosa

Table 28 and figure 10 show the number of fires and fire injuries for coal preparation plants by state during 1990-1999. Table 28 also shows the risk rates, employees' working hours, and lost workdays by state. For coal preparation plants, 91 fires occurred in 1 1 states during 1990- 1999. Twenty-three of those fires caused 25 injuries (the yearly average was 9.1 fires and 2.5 injuries). Ten fires and eight injuries involved contractors. The Ewhr value was 24 1 x 10' hr (Irr = 0.02 l), and the LWD value was 198. Pennsylvania had the most fires (24 fires and 4 injuries), whereas West Virginia (22 fires and 7 injuries) and Kentucky (22 fires and 7 injuries) had the most fire injuries. Among these states, Kentucky had the highest injury risk rate value (Irr = 0.025). Table 29, partly illustrated in figure 11, shows the number of fires, fire injuries, risk rates, employees' working hours, and lost workdays by time period. The number of fires decreased during most of the periods (an increase is seen only during the last period). The number of fire injuries show a decrease followed by an increase during the periods, accompanied by a decline in employees' working hours throughout the periods. The Irr values follow patterns similar to those shown by the injury values (see table 29 and figure 11). Tables 30-35 show the number of fires by ignition source, method of detection and suppression, equipment involved, location, and burning material by time period. Figure 12 shows the major variables during 1990-1999. Table 36 shows the fire injuries per number of fires causing injuries and total fires by year, ignition source, equipment involved, and location.

Jan 1, 2004

By R. P. Beyer

Low-temperature heat capacities and standard enthalpy of formation of copper difluoride (CuF2) were determined by the Bureau of Mines. The low-temperature heat capacities were determined from 11 to 302 K by adiabatic calorimetry. The enthalpy of formation was determined by HC1 solution calorimetry. The standard values of entropy (S°) and enthalpy of formation (?Hf°) at 298.15 K are l8.65±0.03 cal/deg mole and -129.02±0.29 kcal/mole, respectively.

Jan 1, 1978

By Nicholas T. Zilka

One mineral deposit in the Golden Trout Wilderness has potential. The currently producing Pine Tree Mine on the Little Kern River has an estimated 120,000 tons (109,000 t) each of indicated and inferred reserves averaging 0.77 percent tungsten trioxide. No apparent potential exists for base or precious metal or other mineral deposits. INTRODUCTION The Golden Trout Wilderness, established by Congress in 1978 under Public Law 95-237, encompasses 240,000 acres (97,000 ha) of conifer-forested, rolling, upland plateau at the headwaters of the Kern River in Inyo and Sequoia National Forests (fig. 1). Abundant streams locally contain Golden Trout, namesake of the area. Major roads serve the area to the west and east of the Wilderness; access is poor to the north and south.

Jan 1, 1982

By R. L. Montgomery

Electronegativities of the rare-earth elements were calculated from heats of formation. The values obtained from different compounds varied widely. The postulates of Pauling's electronegativity theory were interpreted for bonds that are primarily ionic; the study showed that many compounds obey rules of the form expected. Revised electronegativity values are given for the more electropositive elements, including the rare-earth metals (which are near magnesium in electronegativity). Estimates of un-known heats of formation are made from electronegativities and are compared with other estimates. INTRODUCTION Calculation of the electronegativities of the rare-earth elements is interesting to show how these metals stand relative to the other metals and to each other, and also possibly to systematize the thermochemical data on them.

Jan 1, 1960

By C. M. Flynn

The Bureau of Mines prepared and investigated xanthated sawdust adsorbents to determine their effectiveness in removing heavy metal ions from dilute aqueous solutions, mine-drainage waters, and brines. Stripping of the metal values from the metal-laden adsorbent was also investigated. The treated sawdusts had an adsorption capacity of 0.3 to 0.4 meg/g dry adsorbent for Mn, Co, Ni, Cu, Ag, Zn, Cd, Hg, or Pb from feed solutions with pH 5 to 6. The feed solutions tested included mine-drainage waters and geothermal brine. Effluent metal concentrations as low as 0.05 to 0.1 mg/l were obtained at effluent pH values of 6 to 9. The order of affinity of metals for the sawdust adsorbent is Na«Ca~Mg~Mn<Zn<Ni<Cd<Pb~Cu. The presence of Ca, Mg, or Na in concentrations as high as 2 g/l does not seriously impair the heavy-metal adsorption. Metals were desorbed from the metal-laden adsorbent by elution with dilute mineral acids, sodium cyanide, or salts of ethylenediaminetetra-acetic acid.

Jan 1, 1979

Develop methods of enhancing and measuring the high-temperature softening and melting properties of iron oxide pellets reduced under simulated blast furnace smelting conditions. Approach Add dolomite and Limestone flux and a low-cost organic binder, such as starch, carboxyl methylcellose (CMC), or waste papermill sludge, to the iron oxide concentrate to produce hematite (ferric oxide) pellets with superior high-temperature metallurgical properties. Simultaneous increases in softening temperature, gas permeability, and enhanced metallization rates are sought to improve blast furnace productivity and energy efficiency. Background In the past, bentonite, an inorganic binder, was the only additive (binder) used in the production of pellets made from iron ore concentrate. Research has shown that the reducibility of conventional (acid) pellets can be increased by the addition of flux or an organic binder. The increase in pellet reducibility results in less wustite in the center of the pellet at high temperatures, such as those obtained in the cohesive zone of the blast furnace.

Jan 1, 1990

By P. A. Surgeon, R. R. Sayers

It is not the purpose of this report to try to describe all the work done during the past year for the improvement of health or the prevention of illness among miners , but to call attention to a few of the more outstanding investigations in which progress has been made . Among these , the investigations on the physiological effects of carbon monoxide , dust and ventilation , and temperature and humidity will be discussed . Carbon Monoxide . During the years 1920 and 1921 , much more work has been done on the various A survey phases of carbon monoxide than has been carried on for a number of years . of carbon monoxide poisoning in the American steel works , metal mines , and coal He conmines was made by Dr. Henry S. Forbes , of the Harvard Medical School . ** cludes from his survey that late after- symptoms following acute severe gassing rarely occur , and that almost always there is evidence of pre - existing pathological conditions when such effects do appear . He further states that he found no evidence of cumulative harmful effects resulting from frequent exposure . Dr. Forbes , Dr. Forbes , assisted by Louise Hompe , made a laboratory investigation in which anesthetized animals were exposed to carbon monoxide , illuminating gas , and benzol *** . The investigators conclude that , under the conditions of their experiments , there is no change in the coagulation time of the blood . It has been stated by many investigators that the blood of those affected by carbon monoxide does not clot as quickly as normal blood . While the investigation referred to above may not cover all the conditions , it is a valuable contribution to the subject as it indicates that the small hemorrhages found in the membranes covering the central nervous system , abdominal organs , etc. , at autopsy of those dying of carbon monoxide poisoning is probably not due to direct toxic action of the gas upon the blood .

Feb 1, 1922