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By Chris Jobes, Alan Mayton, N. Kumar Kittusamy, Dean Ambrose

NIOSH researchers conducted a study to compare seat designs on underground coal mine haulage vehicles. The objective of the study was to support prior findings that NIOSH-designed seats, which incorporated ergonomic design features (e.g., viscoelastic foam padding and low-back support), are improved designs. Based on measured levels of vehicle jarring/jolting and perceived discomfort, researchers evaluated four different designs - two in-use and two NIOSH-developed, ergonomic designs. Researchers collected data using a short questionnaire, a linear, visual analog scale, and accelerometers with a data recorder. Results showed that vehicle operators favored the NIOSH seats with added adjustability, low-back support, and improved seat padding over the existing seats. In addition, the measurements indicated all NIOSH seats performed better than the existing seat, under the no-load (worse of two) conditions, in reducing peak acceleration, crest factor, and RMS acceleration. The authors summarize the data collected and operator preferences for seat designs and different foam padding arrangements.

Although the mining industry has achieved record-low fatalities and injuries for each of the last three years, there are still too many miners injured or killed in this nation ís mining operations. Many mining injuries or deaths might have been prevented by using risk assessment to identify and control or eliminate the hazards associated with a task. To focus attention on the importance of conducting risk assessments in keeping mining workplaces safe and healthful, MSHA introduced this initiative on October 12, 2004. This initiative is called SLAM. SLAM is an acronym for Stop, Look, Analyze, and Manage. The steps involved in SLAM are: Stop ñ stop and consider the work involved Look ñ look for and identify the hazards Analyze ñ analyze what needs to be done Manage ñ manage safety by developing and implementing controls Everyone should be aware of the risks of an accident before beginning a task. It may not always be obvious that performing a seemingly routine task could result in an accident. That is why conducting a risk assessment is so important. Itís important to remember that over time a mining workplace seldom remains unchanged. Risks must be assessed whenever procedures or processes change, whenever new tasks are started, or non-routine tasks are performed.

Jan 1, 2005

By Charles A. Kumbe

"INTRODUCTION The Sullivan Mine was examined by Thomas L. Chapman, an engineer of the Bureau of Mines, in March 1943. Samples taken from the few mineralized exposures justified further investigation of the property. To determine whether extensive exploration of the property would be warranted, the Bureau did a small amount of trenching and underground work during April 1943, 3/ under Bureau project 1462.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its, primary objective the, more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratary project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurigical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests.The investigations of the and Metallurgical Branches of the Bureau, as reported in this paper, were supervised by J. Hedges, district engineer for Arizona, and S. R. Zimmerly, regional engineer for the Western Region, respectively."

Feb 1, 1947

By Henry P. Chandler

THE year 1950 was one of increased activity in almost all branches of the abrasives industry, with nearly all abrasive materials showing a marked increase in tonnage and value. New records were made In the production of tripoli, ground sand and sandstone, pumice and pumicite, and garnet. Total production of crude artificial abrasives in the United States and Canada increased 17 percent in tonnage and 30 percent in value. Imports of industrial diamonds increased 100 percent in total value and 72 percent by weight, the 1950 importation being the largest since 1944. Imports of corundum increased 76 percent in tonnage and 4 percent in value.

Jan 1, 1953

By George H. Schnakenberg

Automation of coal mining activities at the face offers improvements in worker safety, health, and productivity. Introduction of integrated computer-sensor systems to current mining machines will enable these machines to perform some of the most hazardous tasks through supervised teleoperation. The U.S. Bureau of Mines is pursuing the development of the enabling technology necessary to achieve this goal. The research program consists of both basic and applied research, each focused on the fundamental issues of computer and sensor technologies. Short-term research is directed to providing computer-assisted, remote supervisory operation of present underground equipment; the long-term goal is the development of progressively more intelligent mining systems. The research program includes a review of robotic machine and autonomous vehicle technologies and of current mining technology, which provides a base for developing innovative mining methods; research in navigation and guidance technology, emphasizing control of a continuous mining machine; research on coal-rock interface sensing technology for horizon control, and rib thickness control in highwall mining; the development of computer systems and hierarchical architectures for real-time control; and development of expert systems for machine system fault diagnostics and predictive maintenance. This report presents a brief background and the current status for each of these research areas.

Jan 1, 1989

By B. Numerov

A numerical proceeding of corrections with respect to topography is worked out for places near the station and a graphical one for the remote parts of the terrain. The description is clear and very detailed. The numerical proceeding is very similar to that of the Eötvös and Schweydar methods which are in use already. In both methods the levelling is accomplished in certain circles and fixed azimuths around the station. While, in using the Eötvös method, the height differences are directly inserted into the final formulas with regard to the foot of the instrument and in case of accurate formulas derived by Schweydar the height differences are calculated with respect to the center of gravity of the attachment, Numerov introduces functions A and B, the heights, of the terrain and of the center of gravity, which are to be inserted into the formulas.

Jan 1, 1929

By Bill York-Feirn

The Colorado Mine Safety & Training Program (MSTP), in late 2005, completed and began distributing two new training tools; one geared to underground coal mine foremen and the other to surface aggregate employees. Through strong partnerships with MSHA, Colorado Coal Mine Board of Examiners, Colorado Mining Association and the Colorado Rock Products Association, the MSTP continues to create innovative and interactive training tools for not only Colorado, but for the national mining community. "Although we shoot and produce these materials in Colorado, it's important to us to make sure they are useful nationally," said Bill York-Feirn, MS TP Manager. The interactive DVD program "Underground Mine Foreman Certification Study Guide (Coal)," was completed in October 2005. It won the 2005 Grand Prize at the MSHA National Training Materials Competition in Beaver, West Virginia. [ ] This program is fully based upon the requirements of Title 30 Code of Federal Regulations (30 CFR) Parts 48, 50, 70 and 75 for underground coal mine foremen. It contains eight modules plus immediate access to relevant laws in the appendix. Topics covered include: Federal Law, Practical Math Skills, Mine Gases, Ventilation Maps, and scenarios addressing a variety of practical mining concerns. The DVD is designed for self-¬paced study and practice.

Jan 1, 2006

By Robert F. Chaiken

More than 500 fires are now burning in abandoned coal waste banks and coal deposits in the United States. Once established, such fires can burn for decades, and extinguishing them by conventional methods such as surface sealing to exclude air, excavation to remove fuel, or flushing to cool the fire zone is usually difficult and always expensive. Burnout Control, a technique developed by the Bureau of Mines for the control of abandoned fires, involves the accelerated combustion of coal in place with total management of the heat and fumes produced. A burning waste bank or mine is placed under negative pressure relative to the atmosphere, and heat and combustion products are drawn from the combustion zone through an exhaust ventilation system. Heat produced appears as sensible heat in the exhaust, at temperatures as high as 1,000° C (1,832° F), and can be recovered for the production of steam, hot water, process heat, or electricity. The Bureau's first field demonstration of Burnout Control was at Calamity Hollow in Allegheny County, PA (near Pittsburgh). Calamity Hollow was the site of an underground mine in the 1900's and was surface mined in the 1940's. In the winter of 1961-62, a fire of undetermined origin was discovered in the exposed coal. In 1963, the Bureau constructed a trench barrier around the fire and a surface seal over the affected area. The fire was isolated, but not completely extinguished. In 1979, when the Bureau began work on the Calamity Hollow Mine Fire Project, to demonstrate controlled burnout, the fire was still smoldering on the hot side of the trench barrier. The project, which was begun in December 1979 and ended in July 1982, consisted of the design, construction, operation, and subsequent dismantling of a Burnout Control ventilation system. This report is the fourth in a five-part series that describes the Calamity Hollow Mine Fire Project. The first report, part 1, describes the design and construction of the field installation. Part 2 will present the results of a continuous 4-month burnout operation. (Because part 2 involves the analysis of a substantial body of data, it will not be published until after publication of parts 3, 4, and 5). Part 3 describes the instrumentation used to control and monitor the progress of the burnout operation. This part (part 4) and part 5 both deal with the closeout phase of the field demonstration. The quenching of the fire is described in this report, and part 5 will describe the final excavation and backfilling of the heated zones. The reports in this series document the Calamity Hollow controlled burnout demonstration, which showed that (1) controlled in situ combustion is a feasible method for controlling underground fires in abandoned mines, (2) the resultant thermal exhaust output is sufficient for energy utilization, and (3) water injection with fume exhaustion is a potentially effective method for cooling large underground fire zones. Further trials of both Burnout Control and water injection with fume exhaustion are planned.

Jan 1, 1984

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations 4251. The factual data obtained during the project are reported in a series of Reports of Investigations, of which this is the seventh. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate half-township map. The description of each half township is followed by a description of each deposit developed in that half township. The 14 half-township maps and 77 detail maps of the bauxite deposits in , this series of reports give the locations and numbers of all the holes drilled on the project, except the deep holes drilled to test the geophysical anomalies. The locations of those holes are shown on figure 13 in volume 1. The descriptions of the deposits developed are followed by complete detailed logs of the drill holes. Many of the widely spaced exploratory holes did not discover bauxite of .1 minable thickness and grade. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated, and a table for each half township is given with the discussion covering that area.

Jan 1, 1948

By C. E. Augustine, B. A. Landry, P. Nicholls

"Wien bituminous coal is burned in a hand-fired up-draft boiler used for heating purposes it has a decided tendency to produce smoke. A design of furnace and a method of firing and attendance that are satisfactory for fuels low in volatile matter, as anthracite or coke, are not necessarily Satisfactory for bituminous coals. It is therefore becoming common practice to use a special design of furnace for bituminous coals, in order to facilitate the combustion of the volatile matter and soot. This is done by (1) providing a larger combustion space to give more time for the combustion, (2) construction that will produce a better mixing of the gases and secondary air supplied over the fuel bed, or (3) keeping the gases at a higher temperature by preheating the secondary air, as may be done by surrounding them with refractory surfaces, or causing them to pass through a fuel bed of hot coke. A furnace may be built to use any or all of these methods of smoke prevention.In Bureau of Mines Technical Paper 303, Blizard5 and others give tests on a large heating boiler when burning coke, anthracite, and bituminous coal. Certair alternative furnace arrangements were used, but there was no material change in the furnace design for the various fuels. Since that time the manufacturer has made modifications in design to adapt it for use of bituminous coal, and additional tests have been made to determine how this change affected the production of smoke and the efficiency of the boiler."

Jun 1, 1929

By Mark R. Pettitt

The results of an extensive research and development program to reduce the noise generated during coal cutting are presented. The characteristics and magnitude of continuous miner coal cutting noise sources are defined. This work consisted of development of a simulated coal ,cam to facilitate above-ground coal cutting tests, noise measurements in a reverberant acoustic chamber during simulated mining operations of a continuous miner (cutting the simulated coal scam), and noise measurements in an underground coal mine during continuous miner operation. In-mine and laboratory test results were in excellent agreement for both A-weighted overall levels as well as A-weighted one-third octave band spectra. Methods to reduce coal cutting noise are presented. These methods take full advantage of the dynamic characteristics of the forces generated during coal cutting. Dynamic cutting force isolation was shown to be a very effective technique. Finally, a continuous miner was equipped with a cutter head that incorporated (among other design factors) cutting force isolation. Successful, lung term, in-mine use of the cutter head demonstrated coal cutting noise at the operator's station of less than 90 dBA and 50% coal, 50% rock cutting of less than 93 dBA.

Jan 1, 1985

By R. V. Lundquist, A. E. Morris, E. L. Singleton

This experimental research was performed to determine rate - of - reaction constants on the MnO - C and Mn , C₂ - 3MnO systems at 1,100 ° , 1,150 ° , and 1,185 ° C. Reactions were conducted at atmospheric pressure under controlled flow of purified helium through the furnace chamber . The weight - loss method defined reduction percentages , and reaction products were identified by X- ray methods . The system Mn0 - C followed a linear reaction rate , and experimental results produced an apparent activation energy of 55.8 kcal per mole of Mn0 . The system Mn, C - 3Mn0 followed a parabolic rate of reaction law and yielded an apparent activation energy of 114.4 kcal per mole for the reaction .

Jan 1, 1964

By James S. Browning

Research by the Bureau of Mines demonstrated that organic heavy liquid adhering to or adsorbed on fine mineral particles can be effectively removed by a novel method embracing pulping or displacement washing with hot water alone or in combination with a detergent. Displacement washing with steam alone or in combination with a detergent also was effective for removing the heavy liquid. In tests of sized minus 48-plus 200-mesh mineral charges, both the hot water washing with detergents and detergent steaming effectively reduced the heavy liquid losses on the particles to about 0.2 pound per ton of mineral or less. Centrifuging of the wash solutions permitted an almost complete recovery of heavy liquid from the solution as a pure heavy liquid product.

Jan 1, 1966

By William Porter

Hand scaling is a physically demanding job and is responsible for numerous overexertion injuries in mining. This experiment studied rib scaling from an elevated bucket to examine force generation capabilities and electromyographic responses to a prying subtask. Subjects exerted force using two bars (steel and fiberglass) at five target heights. Work height significantly affected peak prying force during scaling activities with highest force capacity at the lowest level (p = 0.0188). Bar type did not affect force generation (p = 0.7843): However, use of the fiberglass bar required significantly more muscle activity to achieve the same force (p < 0.05). It was concluded that miners should scale points on the rock face that are below their knees, and reposition the bucket as often as necessary to do so. Additional research is needed to fully understand the impact of bar type on the physical demands of an entire scaling task.

Jan 1, 2006

By Paul M. Tyler

The colony of French Guiana ( or Cayenne ) is administered by a governor , assisted by a privy council of five members . A council - general of 16 members is elected by French citizens resident in Guiana, and the colony is represented 3 in the French parliament by one deputy . The area is about 34,740 square miles . French Guiana is the largest gold producer of the French colonies , producing nearly $ 1,000,000 worth annually . Considerable prospecting has been done on the bauxite deposits , which are extensive . Copper , iron , lead , and 4 mercury deposits are also reported . In 1931 , 10,000 prospectors for gold were reported as working . The French Government is taking an active interest and has sent a committee of mining experts to explore the region ; no permits are to be issued to individual prospectors while the committee is in the colony . Plans for development of mining industry include consideration of 4,500 convicts and 2,500 natives already in the colony and available for labor .

Apr 1, 1933

By Robert H. Townsend

The following paper discusses the mining, transportation, and crushing methods, with costs, at the San Andreas plant of the Calaveras Cement Co. It is one of a series, prepared for and published by the U. S. Bureau of Mine describing methods used in cement-rock quarries throughout the country. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total cost. It is recognized that publication of total costs mightin some instances cause embarrassment to individual producers as well as to the industry as a hole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost-tabulations shall ensue.

Jan 1, 1933

By Larry L. Wischhoefer

The Automated Breathing Metabolic Simulator (ABMS) is a versatile machine capable of performing almost any physiologically appropriate respiratory simulation. The first ABMS was delivered to the Bureau of Mines by IBM in 1973. Since then efforts have been made to refine the systems and components which make up the ABMS including the Breathing Simulator Module (BSM), Gas Analysis Module (GAM), and Supervisory Controller (SC)-each of which are also capable of stand-alone operation. Since September 1980, Reimers Consultants has been testing and modifying the ABMS and its components in order to improve the equipment and to develop simulation criteria and parameters. Changes have been made to the Phase I Design Plan and Performance Specifications; future improvements based on current experience are recommended; and test results of full scale testing conducted by Reimers Consultants in November 1983 on several types of breathing apparatus are reported and illustrated.

Jan 1, 1984

By L. B. Pankratz

Thermodynamic data on the halides were reviewed, evaluated, and compiled at the Bureau of Mines Albany Research Center. Values for Cp°, S°, H-H°298, -(G°-H°298)/T, ?Hf°, ?Gf°, and log Kf are given in tabular form. CP°, H-H°298, ?Hf°, and AGf° are also expressed algebraically.

Jan 1, 1984

By NEFE AEWFW

Changes in the 1980 quantity and value of the sales of various natural abrasives, compared with the data for 1979, were of a mixed nature. Output of garnet and special silica stone products increased in both tonnage and value during the year, while emery and tripoli-type materials production decreased in both tonnage and value. The reported quantity and value of sales of manufactured abrasive material-fused alumina and alumina-zirconia, silicon car-bidet and metallic iron and steel shot and grit-also decreased for 1980. [ ]

Jan 1, 1981

By D. C. Dahlin

To identify and characterize potential domestic chromium resources, the Bureau of Mines investigated podifom chromite deposits along the Border Ranges Fault in southern Alaska. Part 1 of this two-part report describes an extensive field investigation and preliminary resource evaluation studies by the Bureau&apos;s Alaska Field Operations Center. This paper, part 2, describes the mineralogy of 38 samples that were collected from low-grade deposits in the Chugach Mountains, on the Kenai Peninsula, and on Kodiak Island, and presents the results of laboratory batch beneficiation tests designed to concentrate the chromite. The samples are peridotites and chromites that consist primarily of variable amounts of chromite, olivine, and serpentine. They were beneficiated by a sequence of grinding, sizing, and gravity concentration operations. Twenty-four high-chromium or marginal high-chromium chromite concentrates, six high-iron or marginal high-iron chromite concentrates, and five submarginal concentrates were produced with chromium recoveries that ranged from 37 to 95 pct. Three very low-grade samples were not beneficiated. These results indicate that several of the de- posits may be significant chromium resources, Potential precious metals association with the chromite was also investigated. Analysis of these samples indicates that the chromite deposits are not good platinum sources.

Jan 1, 1985