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To restore ventilation and prevent the accumulation of explosive or toxic gases by quickly installing substitutes for stoppings blown down by an explosion. Approach Temporarily replace blown down stoppings with a parachute-shaped brattice which can be erected in minutes. How It Works The self-sealing brattice is secured to the roof, ribs and floor by anchoring its nylon edge strip at several points using extensible poles, shads, or available projections such as roof bolts. The air pressure in the entry pops open the chute of lightweight sailcloth, forcing it tightly against floor, roof and rib. See Figure 1. This emergency brattice has been tested at two locations in the Bureau's Experimental Mine at Bruceton, Pennsylvania. In a test last December, one MESA inspector wearing full rescue apparel (including self contained breathing apparatus) installed a self sealing brattice in an entry at the Bruceton Mine. Although he did not have any previous experience with the device, he easily erected it in slightly less than 10 minutes, using two extensible supports (pogo sticks). Research to improve and refine the self-sealing brattice is continuing.

Jan 1, 1977

By Francis E. Federspiel

Silver and gold are the principal metals in the study area; they occur in quartz veins or silicified portions of shear zones. In some deposits, lead, antimony, zinc, and molybdenum are associated with gold and silver. A uranium-bearing buried stream channel lies near the southern boundary. Since 1850, more than 300 lode claims and relocations have been recorded mainly in the southeast corner of the study area (fig. 1). Complete mine production records are not available; however Clark (1977, p. 28) reported less than $300,000 of gold and silver were produced, mainly from the Exchequer, IXL, and Pennsylvania Mines. Other mines in the area probably yielded are before 1900, but early records are not available.

Jan 1, 1981

By D. F. Smith

The thermodynamic data presented in the literature for zirconium compounds are incomplete. Among the compounds for which adequate data are Zacking are zirconium fluoride and sulfate. This paper reports experimental heat-content values determined by the Bureau of Mines for these two zirconium salts throughout the temperature range of 273° to 1,200° K. No crystalline transformations were found in the two compounds investigated, and neither of the compounds melted over the temperature range studied. MATERIALS TESTED The Oak Ridge National Laboratories, Oak Ridge, Tenn., supplied the two zirconium salts used in this investigation. The zirconium fluoride was high- purity reactor grade material. The zirconium sulfate contained between 0.01 and 0.10 percent hafnium and calcium, and other elements in concentrations below 0.01 percent, A spectrographic analysis of the two compounds is given in table 1. Before use the compounds were dried at 400° C. for several hours to removed adsorbed moisture.

Jan 1, 1962

By Sidney Katell

Philippine laterite and serpentine ores can be utilized in an electric furnace operation to produce both a steel ingot and a ferronickel product. Figure 1 is a schematic interpretation of a plant in which laterite and serpentine ores are processed separately to obtain both ferronickel and steel as products. A relationship of estimated capital requirements and probable returns has been established in this study for a plant of this type. No attempt has been made to evaluate the risks involved in commercial operations. At such time that the project might be constructed and placed in operation, changes in the costs of material, labor, and power may materially affect the profitability aspects of this study. One of the uncertainties involved in the economic evaluation is the cost of mining, handling, and shipping the ores. It is on this basis that the cost of ore delivered at the plant is assumed to be variable at $3, $5, and $7 per net ton (dry basis). For all other costs a plant site at Iligan City, Philip-pine Islands, has been assumed in preparing the economic characteristics for a plant that will process 2,000 tons4/ of ore per day. Results of the study, for the 2,000-ton plant, with all monetary values expressed in terms of United States currency (Philippine peso valued at $0.50), are summarized as follows:

Jan 1, 1962

By G. L. Barlett, J .. D. Barry

Supernatant media of dust-exposed pulmonary alveolar macrophages (PAMs) were inactive in assays for both Interleukin-1 and fibroblast growth factors (FGF). We have begun to evaluate several factors that may interfere with dust-PAM interactions. To determine the effect of sterilization on the activity of dusts, PAMs were exposed to autoclaved dust, heat-sterilized dust or to dust that had not been heated. Supernatants from the first two groups were inactive in the FGF assay, but supernatant from PAMs exposed to unheated dusts stimulated growth of lung fibroblasts. Recent data have revealed that freshly crushed mineral dusts possess labile free radicals that are absent in dust that has been stored for more than a few days. Suspensions .were prepared of a "stale" sample of anthracite dust 867 and of a freshly ground sample of the same dust. These suspensions were instilled intratracheally into guinea pigs under general anesthesia. Two, five or eight days later, PAMs were collected from the lungs by bronchoalveolar lavage, and the cells were counted. At two and five days after instillation, all lavage suspensions contained 70 to 85% PAMs, of which 5 to 18% contained phagocytized dust particles. On day eight there were again 80-84% PAMs in all suspensions, but in the presence of "fresh'" dust, 48% of PAMs. had phagocytized particles in comparison to 16% in the presence of '"stale'" dust. A similar experiment was performed in short-term cell culture. During 24 hours, >95%. of PAMs phagocytized dust particles, whether or not the dust was "stale" or '"fresh". Our studies are being extended to determine the effect of (1) removing surface oil contaminants by organic extraction and (2) suspending dusts without surfactant.

Jan 1, 1988

Another major aluminum company announced intentions to follow other domestic producers recent price actions by raising its unalloyed ingot quotes by 3¢ to 44¢ per pound, effective June 1, 1976. COBALT: All final data for 1975 are included in the table for cobalt on page 23. Demand in March increased significantly for the second month in a row, signaling a recovery from the previous year's relatively low demand levels. Imports of cobalt tripled in March over those of February. This should partially offset reduced sales of cobalt excesses from the National Stockpile. Import projections for the next several months have been lowered because transportation difficulties in Zaire are expected to result in reduced shipments.

Jan 1, 1976

By T. J. Lutz, G. T. Homce

A standard Ford1 4600 agricultural tractor was converted to remote control to perform ASAE/SAE field upset tests (rear rollover and side rollover). This paper discusses the engineering process to develop a remote-controlled tractor in determining the critical parameters of operation, to choosing appropriate actuators, designing the circuitry to control them, installing the actuators on the tractor, testing the system for functionality and then conducting numerous overturn tests. The system uses off-the-shelf components for simplicity, replaceability, and economic concerns. The remote control system has withstood 21 tests to date with no failures and will continue to be used for at least three more years of testing.

By Rudolf E. Greuer, Linneas W. Laage, Xinton Chang

All output is saved in the file MFIRE OUT m the di¬rectory and on the disk containing the program The file can be inspected with a text processor and sent to a print¬er, if needed CONTENTS OF OUTPUT FILE The comment lines, reference temperature, air densi¬ty, a table of the units of measure for the results, and the average values are shown at the beginning of MFIRE OUT All input data will be shown in the output file if LOUT on Control line number 1 is _<-1 For each contamination source, a new branch will automatically be setup The new airway and junction ID numbers will not interfere with the original numbering scheme of the data file Next are the results of the selected simulation(s) in the following order network balancing, network balancing considering temperatures, transient-state modeling, and altered equilibrium due to fire and distribution of the contaminants. Depending upon the contents of the data file, and the simulation selected, attention, warning, and error message will be shown at locations where calculations resulted in unusual conditions

Jan 1, 1990

By William A. Hustrulid

An overall summary and the individual reports of eight workshops to determine research and development needs in western mining ore presented. Problem areas are identified, and recommendations regarding priorities, funding sources, and prime movers are made. The objective of this contract was to identify research and development needs for advancing mining technology as well as health and safety measures for western U.S. Surface and underground mining. This was accomplished by convening a series of workshops where problems could be thrashed out by producers of trona, uranium, open pit copper, underground salt (from the Midwest and New York), underground metal and nonmetal, etc. In addition to problems, future priorities, funding, and the desicion as to who should be the prime mover on R & D were discussed.

Jan 1, 1976

By R. Agarwal

The in-situ stress field was determined, using the overcoring technique, at two underground sites at the Pea Ridge Mine, Sullivan, Missouri. At one of the sites in magnetite, the three dimensional stress field showed the largest principal stress to be compressive (-4564 psi), nearly horizontal and closely parallel to the strike of the orebody. The smallest principal stress was also compressive (-2047 psi) and nearly vertical. Considerable difficulty was experienced in drilling porphyry rock at the second test site in the host rock. Only one hole was drilled at this site. The secondary principal stresses obtained in the porphyry are -9464 and -4945 psi, respectively. The-test site in magnetite is located at a depth of 2505 feet whereas the site in porphyry rock is at 2475 feet. The vertical stresses: due to overburden loading at these sites are -3590 and -2782 psi, respectively. Field determined values of the vertical stress are -2207 and -5098 psi, respectively. The variance; between the two sets of values is most likely attributable to the orebody formation and the differences in the modulii of the host rock and the orebody.

Jan 1, 1977

By Lloyd A. Morley

This report abstracts project work performed under USBM Grant GO155003 during the period 4 November 1975 to 3 November 1976. The research was funded, as a continuance of previous support from USBM Grants GO133077 and G0155003, to gain further knowledge in mine electrical system safety. Five reports have been separately produced, all under the grant title, "Coal Mine Electrical System Evaluation," and are as follows: 1. Volume I - Continuous Monitoring, 2. Volume II - Transient Analysis, 3. Volume III - Shielded Cables, 4. Volume IV - Computer Modeling, and 5. Volume V - Battery and Battery-charging Safety. Abstracts of these comprise the balance of this document with one exception. The task ?d-c offsett currents," does not fall under the scope of the other report volumes and, further, the material to be presented does not justify a separate report. Hence, this subject concludes the Executive Summary.

Jan 1, 1977

By A. E. Ketler

The Bureau of Mines Research Program has defined per coal miner&apos;s illumination needs. Due to similarity in the environment in which coal and Hardrock miners work, coal mine illumination technology has been applied to Hardtack room and pillar mines.

Jan 1, 1977

By George A. Savanick

An experimental hydraulic jetting device intended to operate in a 16-in-diam borehole was designed, fabricated, and used to cut coal and simulated coal samples. This device consisted of two 0.107-in-diam nozzles that rotated in a plane perpendicuIar to a 50-inch length of high-pressure tubing. Experi¬ments were also conducted with stationary jets issuing from a single 0.142-in-diam nozzle. Numerous experiments were performed using systematic variations of jet parameters coupled with assessments of cutting rates. These Bureau of Mines tests showed that when operated at 4,000 psi pressure and a 40-gpm flow rate (1) the device can fragment coal up to a distance of 8 feet from the nozzle, (2) 4,000-psi jets cut more effectively than lower pressure jets with the same nozzle diameter, (3) stationary jets do not cut as effectively as moving jets, (4) interkerf breaking occurs when the kerf spacing is less than 2 inches, and (5) if the kerfs are spaced <1/2 inch, the jet is deflected and thereby reduces cutting effectiveness.

Jan 1, 1975

By Alice Turcot

Knowledge of risks from exposure to hand-arm vibrations is usually presented by clinicians and researchers from a medical and engineering point of view. There is a strong need to develop innovative health promotion programs for exposed workers. Risk perceptions by vibration exposed workers and HAVS (hand-arm vibration syndrome) affected workers are less well known. In 1983, Brubaker demonstrated that 75% of studied fellers thought that whitening of the fingers was part of the job and/or an unrelated nuisance, while only 25% believed it was a disease. 1Grounds also showed that even though there were a very high number of forestry workers with white fingers, none considered quitting because of their condition. 2 It seems that many workers hesitate to declare the illness or believe they are less affected than they really are, perhaps from fear of losing their jobs and livelihood. 3 Risk awareness, on the part of exposed workers and their employers, as well as knowledge and acceptance of available preventive solutions are necessary steps before installing adequate preventive measures, whether organizational, behavioral or environmental. Workers need to understand fully the hazards and risks in order to be able to make informed decisions under uncertain conditions.4 Prerequisites include the following: workers knowledge about the risk, their attitude towards it, which in turn, can be influenced by values, needs and interests. Also, knowledge and attitudes towards safety behaviour, organizational or environmental barriers must be taken into account. Our research focuses on these key elements, which help bridge the gap between health promotion research and practice. Methods A descriptive exploratory study is in progress with workers exposed to hand-arm vibrations. It uses qualitative methods that include focus group discussions with workers exposed to hand-arm vibrations, as well as individual interviews with other key informants (employers, health care professionals). An open-ended questionnaire was developed to collect qualitative data on perceived risks and solutions to prevent or reduce HAVS. Based on an integrated theoretical framework related to known determinants of behavior change, the analysis will focus on the following5: 1) knowledge of health effects, safety, well-being and/or quality of life 2) related beliefs about individual susceptibility and severity of consequences 3) attitude and values related to hand-arm vibration exposure 4) knowledge and attitudes towards exposure reduction, as well as perceptions of barriers and facilitating factors for these measures, in the workplace environment or otherwise.

Jan 6, 2006

By F. S. Kendorski

This report covers the work on developing criteria for determining when a hazard exists when mining stratified mineral deposits beneath bodies of surface water. The nature of water bodies is considered, the disturbance to the strata induced by mining is described, inundation case histories reviewed, reasonable water inflows derived, and methods of mining to prevent or minimize the hazard are presented. Criteria are given whereby effected industries and agencies can recognize a potential hazard and plan a mine accordingly, releasing considerable mineral reserves otherwise considered unminable.

Jan 1, 1979

By William C. Cooley

This study Identifies and evaluates deposits of noncoal minerals in the U.S. which are most amenable to be mined underground hydraulically and transported hydraulically. A method was developed to screen and compare mineral deposits including economic comparisons. The most applicable minerals for hydraulic mining by borehole monitor jets from underground entries are soft uranium sandstones In Wyoming in locations where water is available. This method with hydrotransport could improve the safety, health and economy of underground uranium mining. Soft oil-bearing sandstones in California and Texas could be mined and transported by this method more safely than by other underground mining methods. Other weak sandstones may be hydraulically mined economically. Man, minerals are too hard to be mined by monitor jet but are amenable to hydraulic transport and hoisting. Uranium sandstone in New Mexico is of interest because of potentially improved health and safety in transport and lower transport cost, Increases in mine output for potash, in New Mexico and trona in Wyoming can be achieved most economically by adding hydraulic hoisting when existing skip capacity is at its limit. Research is recommended to obtain site-specific data on the feasibility of mining uranium ores by monitor jets.

Jan 1, 1981

By N. R. Dixon

This report summarizes all work performed under U.S. Bureau of Mines Contract No. J0395028, "Noise Control of Rubber-Tired Front-End Loaders Used in Surface Mining. " Two loaders, a Caterpillar 988 and an International H-400B, were chosen for this program, and the noise sources and acoustic paths that contribute to the operator&apos;s noise exposure were identified. Retrofit noise control treatments were designed and installed on these loaders, and noise reductions of more than 10 dBA at the operator position were achieved on both machines. The retrofit packages are low cost and have been field tested in two mines for more than two years. The results of the program were communicated to the mining industry through a series of noise control workshops and a field manual. The workshops were given in nine states across the U.S. and more than 440 manuals were distributed An audio/visual slide presentation was also developed which the program.

Jan 1, 1983

By Rudolf E. Greuer

This report contains the practical application of a computer program for the simulation of ventilation systems under the influence of mine fires and other emergencies on five hardrock mines. The introduction describes the need for such a program, its basic features, and the range of its applicability which is mainly a function of the available ventilation data. The second chapter discusses program modifications, whose necessity or desirability was, during the application, discovered. The following five chapters, which comprise the major portion of the report, give the detailed description of the program application on the five mines. For every one of the selected mines, the ventilation system, the source of the used ventilation data and their preparation for computer simulations are outlined. Based on data for the airflow distribution solely, fumes concentrations in the mines are calculated for several assumed fire locations. Based on data for airflow and pressure distributions, ventilation disturbances caused by fires as well as the resulting fumes concentrations and temperatures are determined. The consequences for escape routes and the possible means to keep them free of fumes are discussed. To investigate the capabilities of the program, other contaminant sources and other potentially dangerous ventilation factors, like fan failures and changed surface temperatures, are simulated also. The results of the calculations have been entered into ventilation plans which makes them easier to scrutinize. All significant computer printouts have been attached.

Jan 1, 1981

By F. T. Eddingfield, F. E. Wormser

"The premium on gold in London, reflecting the further depreciation of the pound sterling, has risen from about 22 per cent as noted in these reports for December, to about 28%. This will enable more South African gold mines to come into the profitably ;reducing class, and will also tend to increase the gold production from that region.Figures are now at hand showing the drop that occured in the sold output in the Transvaal, South Africa, during 1919, in which year 8,330,091 ounces of gold were produced against 8,418, 292 ounces in 1918, a decrease of 88,200 ounces. Annual gold output from this, the most important gold area in the world, has dropped almost one million ounces in the past three years, as the following table shows:Although the decrease in not as marked comparatively as that of 1918 over 1917, it is a further indication of the general world-wide curtailment of gold production, and the steady decline in production everywhere that is going on and will continue until some rational means is found to stimulate production, or until conditions return to normal.The subject of relief for the gold miner has received attention in all parts of the world, particularly in the United States and South Africa in the past few years, but in spite of all the plane that have been formulated to remedy the situation none have yet been adopted anywhere, due mainly to great danger of tampering with the gold standard. In the United. States a plan has advanced by H. N. Lawrie of the American Mining Congress to tax the new gold entering into manufacture of jewelry or the arts in general, as furnishing some measure of increased compensation to unprofitable gold mining.Gold production in Australia, as indication by figures issued by the Australian Mines department, shows a marked decrease, and for the first ten months of 1919 amounted to 914,957 ounces against 1,073,317 ounces for a similar period in 1918. Western Australia produces about two thirds of all the gold rained on that continent. The total gold production of Australia for 1919 will reflect the universal decrease in output.Ever since June 7, when the embargo on the export of gold Was lifted, there has been steady and heavy outflow of gold from this country, as a consequence of which considerable gold accumulated during the war has been exported. Changes in the gold money stock of the United States are shown by the following table:"

Jan 1, 1920

By J. D. Noll, S. E. Mischler

Measurement and sampling of diesel particulate matter in mine air presents a challenge due to the complexity of the diesel aerosol. The results of a series of tests carried out by the National Institute for Occupation Safety and Health, Pittsburgh Research Laboratory, in an underground mine were used to evaluate several measurement methods that are currently used to characterize particulate matter emitted by diesel-powered equipment. This paper presents an overview of these techniques and examples of the results along with a discussion of the advantages and information gained by each technique. The measurement methods discussed include particle size measurements using a scanning mobility particle sizer, total particulate matter measurements using a tapered elemental oscillating microbalance, a size selective sampling method for workplace and personal exposure assessment and a size-selective high volume sampling method for carbon analysis.