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By R. Raines, S. P. Signer

Researchers from the Spokane Research Laboratory of the National Institute for Occupational Safety and Health installed 39instrumented, fully grouted bolts at six test sites in a trona mine retreat panel to study mine roof stability for the improvement of workplace safety. Variables at each test site included bolt spacing, bolt length, roof span, and location in the panel layout. At most test sites, two rows of instrumented bolts were installed, one in or near the intersection created during development and the other in or near the intersection created during second-pass mining. The most significant factor affecting bolt load was roof span. The highest loads were on the bolts installed in the intersections of the 6-m-wide entry. Mining-induced stress resulting from panel layout was the next most significant factor affecting bolt loading. Minor variations in bolt loading could be attributed to changes in bolt spacing and bolt length. Gas pressure release in the immediate roof contributed to some bolts showing compressional loading during gas bleed-off.

By Audrey F. Glowacki, August J. Kwitowski, Richard L. Unger, Edward F. Fries

Well-prepared personnel and an effective emergency response plan are essential components of any emergency command center. Unfortunately, evaluating emergency preparedness is often difficult until a disaster actually occurs. For example, unexpected events may develop during an emergency that were not considered during the planning phase. Also, the command center may need to cooperate with organizations that it has not worked with previously. Preparation can be especially difficult for smaller or remotely located command centers, or those with limited resources to conduct mock drills. This paper explores the potential of using the Internet to teach and evaluate command center skills. The National Institute for Occupational Safety and Health (NIOSH) is developing an Internet-based, computer simulation training package for the mining industry. Trainees will play the role of command center leaders at a mine, while the actions of other individuals and organizations are simulated. Trainees will be able to test their emergency response plans and learn valuable lessons from past mine emergencies. Nationally recognized experts will be able to create new training scenarios and make them available to mines throughout the U.S. This product should better prepare command center personnel for large-scale disasters such as fires and explosions. Keywords: emergency preparedness, simulation, training, internet

By Todd M. Ruff

A training software package for new mine employees, called Miner Training Simulator (MTS), has been developed by researchers at the National Institute for Occupational Safety and Health. MTS is a computer-based tool that allows a trainee to enter a simulated mine and interact with his/her surroundings in order to learn basic mining concepts, safety procedures, mine layouts, and escape routes. The training simulator software and instructions for its use are described in this report. Also, each mine using the software will have different requirements with regard to safety training. To customize the simulator for these differences, an interpreted scripting language is used to define interactions between the trainee and the virtual mine and objects in it. The scripting language, called Tool Command Language, uses simple commands to control various actions in the simulation, such as sounds, safety messages, hazards, and movement of objects. The basics of the scripting language are described here, along with many examples and instructions for building a script for MTS.

Jan 6, 2001

By Lloyd A. Morley, Robert Stefanko

The most time-consuming research segment was assembling the ref¬erences. These are provided immediately after the conclusions but are divided into two categories. The first is directly applicable publi¬cations, correspondence and personnel communications. The second listing contains those publications that are not directly tied to the research but where a probable application exists. In both listings, all important USBM publications are provided. The reference numbers used in the report apply only to the first reference portion. Further¬more, it should be noted that all entries are not used but are retained to help anyone who wishes to look further into different or allied areas of this research topic. Explosion-proof enclosures have been researched since approxi¬mately 1906. Even so, little is understood about the mechanism by which they are effective. Due to the voluminous literature published, there is a good probability that the assembled list is still incomplete. The literature search took the following directions. Work was first directed to reviewing the several references assembled by the Department of Mineral Engineering - Mining Section prior to the present project year. As a result, some duplications and inapplicabilities were found and eliminated. The primary sources of the previous search were the commonly available and usually superb library listings, such as Engineering Abstracts. Because these sources have enormous content on all subjects, they were cross-checked in the first semiannual period several times by different individuals to make sure all normally avail¬able literature were uncovered.

Jan 1, 1974

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

BIBLIOGRAPHY 1. Dougherty, John J. , "Control of Mine Fires", Publication of the Mining Extension Service, School of Mines, Appalachian Center, West Virginia University (1969). 2. Coal Age, "Fire, Explosions and Recovery, Federal No. 1 Mine", November, 1963. 3. Nagy, et al., "Sealing a Coal Mine Passage through a -Nor-ii-hole: A Progress Report", U.S. B. M. Publication No. 6453, (1964). 4. Murphy, et al., "Use of Fly Ash for Remote Filling of Underground Cavities and Passageways", U.S. B. M. Publication No. 7214, (1968). 5. Pennsylvania Drilling Company, Pittsburgh, Pennsylvania. Personal Review of Equipment. 6. Industrial Hazards and Communication, Division of U. S. B. M. Personal Communication with John Murphy and Merle Bowser. 7. Instrument Technology, Inc., Borescopes and CCTV Systems for Inspections of Nuclear Reactors; Personal Communication. 8. "Public Works", July, 1972. 9. The Industrial Hazards and Communications Division of the U.S. B. M. , Personal Communication regarding Cohu Model No. 2006. 10. "Bibliography on Underwater Photography and Photogrammetry", Eastman Kodak Pamphlet No. P-124. 11. Optical Properties and Visual Effects of Smoke-Stack Plumes, U.S. Department of HEW, 1967. 12. Middleton, W. E. K. , "Vision Thru the Atmosphere", Univ. of Toronto Press, 1952. 13. Kodak "High Speed Infra Red" film and Singer Corporation Model TI Silicon Vidicon TV Camera. 14. Night Vision Laboratory, Fort Belvoir, Maryland; Barnes Engineering Company, Stamford, Connecticut, Model, T-101; AGA Inc. , Secaucus, New Jersey, Model, "Thermovision" 680.

Jan 1, 1973

Objective Develop field measurement and computer modeling methods to predict the potential for hang-ups and structural failures in underground mine ore paws. Background Analysis of Mine Safety and Health Administration (MSHA) accident statistics has identified ore pass hazards as a significant safety problem in underground metal mines in the United Stales. Recent ore pass failures have underlined the lack or ore pass design methods ant1 standards available to both MSHA and mine engineers. Injury and fatality data for the 20-ycar period between 1975 and 1095 show that nearly 75% of the injuries were directly or indirectly related to pulling or freeing ore pass chutes, the use of hand tools, falls or broken rock, and structural failures or chutes or gates and ore pass walls.

Feb 1, 1998

By C. B. Manula, R. L. Sanford, R. A. Rivell

A generalized flow diagram is presented in Figure 1, which shows the relationship of major model functions. This chart does not necessarily represent the anatomy of the computer program, but is designed to illustrate the informational interchange between major model functions. The related flow-charts-and computer program are listed in Parts I and II, Appendix A, respectively. Mine Car Stations The mine car stations are the activity centers for the model. The locomotive logic structure is designed to provide these stations with adequate cars and to clear them of car buildup. The model is designed to simulate a three stage haulage situation which suggests the need to differentiate station levels by type numbers. These are: a) TYPE 1 stations - mine cars are loaded here; b) TYPE 2 stations - intermediate stop and storage for mine cars; c) TYPE 3 stations - all mine cars that are stored here leave mine; and d) TYPE 4 stations - mine portal. TYPES 1, 2, and 3 have all loaded cars assigned to an ascending TYPE as their next destination. In input, if single stage haulage is designated, TYPES 1 and 3 do not exist, and if two stage haulage is called for, TYPES 2 and 3 are absent. A motor is not permitted to exchange cars between stations of the same type. Station Status Update. One major model function is to continuously evaluate the status of each mine car station. The major evaluations

Jan 1, 1974

Provide a simple and effective means of measuring mining-induced pressure changes in coal mine roof and pillars. Approach Develop a reliable, easy to fabricate and install borehole instrument which measures mining-induced pressure changes in pillars and in the mine roof. Ground pressures are monitored through use of aluminum platens coupled with d copper flat jack. How It Works The Bureau's instrument measures mining-induced pressure changes by transmitting strata pressure through the aluminum platens to an oil-filled borehole platened flat jack (BPF). Pressure in the flat jack is displayed on a gage located outside of the borehole. The instrument is in-stalled in the borehole by inflating the flat jack using a hand-held hydraulic pump. In addition, the platens have been designed to allow up to three BPFs to be installed in a single borehole, thus permitting pressure change measurements in more than one direction from a single borehole. Installation pressure is calculated on the basis of the estimated pressure exerted by the overburden and the percent of recovery after intial mining has

Jan 1, 1986

By John Owens, Wayne Howie, Hamid Maleki

After an analysis of the hazards of room-and-pillar retreat mining systems, it became apparent that safety could be significantly improved by considerations of (1) human factors, (2) remotely controlled mobile roof supports (MRS=s), (3) mine layout designs, and (4) ground monitoring systems. Initial studies of the effectiveness of MRS=s focused on their interaction with mine strata and evaluations of suitable measurements for detecting roof stability problems during pillar extraction. These studies indicated that overall stress distributions and strata movement were most influenced by the stiffness of coal-measure rocks and the design of mining layouts. Thus, to improve worker safety, mine layouts should be carefully designed and a pillar extraction method chosen for specific geologic and stress conditions. Pillar failure was often associated with an increase in pressure on the hydraulic gauges of the MRS, and roof failure was often preceded by rapid changes in the rate of roof-floor convergence. These studies led to development of a monitoring system that displays loading rate on an MRS in real time. A major MRS manufacturer cooperated in installing and testing the system on an MRS. New field studies focus on evaluating the performance of the system, measuring roof-floor convergence, and optimizing the safety of MRS operations through proper mine layout design.

By R. V. Ramani, V. T. Burgos, J. A. McClay

The data for Test I1 describes an underground bituminous coal mine operating in a 72 inch seam, with an estimated production rate of 4,257,000 tons per year. The system includes 15 continuous mining sections, conveyor belt haulage, and a rail network for supply and personnel transportation. The following section includes the input data sequence, annual cost report, and cash flow analysis "report for this data set.

Jan 1, 1975

By W. P. Rumancik, C. P. Lazzara, A. C. Smith

The United States Bureau of Mines (USBM) developed SPONCOM to aid in the assessment of the spontaneous combustion risk of an underground mining operation. A prior knowledge of the spontaneous combustion risk of the coal and factors that increase that risk can be useful in the planning and development of proactive monitoring, ventilation, and prevention plans for the mining operation. Interactive data input screens prompt the user for information about the coal's chemical and physical properties, the geologic and mining conditions encountered in the mining of the coal, and the mining practices employed. During the input process, 'expand' screens provide the user with specific information on each input parameter. This information includes a description of the parameter and its effect on the overall spontaneous combustion risk. The program logic determines the coal's relative spontaneous combustion potential, based on the coal's proximate and ultimate analyses, and heating value. The program then evaluates the impact of the coal properties, geologic and mining conditions, and mining practices on the spontaneous combustion risk of the mining operation. The program output provides details on each factor that increases the risk of spontaneous combustion.

By Thomas V. Falkie, R. Venkataramani

Underground coal winning operations can broadly be classified as conventional, continuous, and longwall mining. In conventional mining, the operations of cutting, drilling, blasting, loading and hauling, and roof support are performed in that sequence in each working face in a work area. The major difference between continuous and conventional mining is that the coal is cut and loaded by a continuous miner in the former, thereby combining the unit operations of cutting, drilling, shooting, and loading into one. Longwall applications have been viewed with great interest in recent years, and although at the end of 1970 there were only 37 longwall installations in the U. S. with combined production of less than 4 percent of underground total, there is no question about the growth potential of longwall in the United States. Increased capacity, versatility, and power characterize continuous miners today. Although continuous miners have outsold conventional gathering-arm type loading machines for some years, the latter, in the new extra-high capacity types, are continuing to find wide use. Whether the mining system is continuous or conventional, the haulage units may include six-wheel articulated shuttle cars, tractor-trailer units, or extensible belt and bridge-conveyor systems, all tending to increase the productivity of the face units. The decision as to which to choose - continuous or conventional mining - is complicated, and both systems are capable of high production rates. Most continuous miners in use today have a revolving pick-mounted drum to cut the coal and a gathering arm loading unit. Functionally, there is little difference between the loading unit in a

Sep 1, 1972

By Oscar Lee

"Flotation is generally regarded as a process that is only applicable to metallic minerals. However, its scope is now known to be greater than this, because some of the nonmetallic minerals are floatable, such as graphite, sulphur, and fluorite. Recent observations show that limestone may be added to the list of floatable nonmetallic minerals. Such work is being done on a laboratory scale at the Southern Experiment Station (Tuscaloosa, Ala.) of the Bureau of Mines, Department of Commerce, where experimental magnetic concentration of the low-grade iron ores of the Birmingham district is in progress. Certain experiments have demonstrated that the limestone may be floated from the magnetic log-washer tailing, and then incorporated in the iron concentrate.If the loss of lime could be prevented, some ores though low in iron and high in insoluble contain enough lime to make their concentrates self-fluxing. Since this loss in the magnetic log-washer can not be avoided, the Time must be recovered from the tailing by some method and added to the magnetic iron concentrate before sintering. Then the resulting concentrate will be self-fluxing.While seeking a suitable means of treating the tailing for recovery of lime, flotation was tried. It was at once evident that this method had possibilities, during the early part of the investigation, soap solution made from a common soap was used as a flotation reagent. The froth obtained was a fairly good lime concentrate. This result was an important clue, and led to tests with the use of such reagents as oleic acid and sodium oleate. Later, cresol, creosote, coal tar and other similar flotation reagents were tested in combination with the oleic acid and soap solutions. As a result, oleic acid and cresol used together were found to be satisfactory.The tailing from the magnetic log-washer is in excellent physical condition fur flotation. The iron ore had been ground in a ball mill to 100 mesh for magnetic concentration. Hence the bond between the lime carbonate and the other constituents of the tailing was well broken."

Apr 1, 1926

Develop and demonstrate a lightweight material that has low thermal conductivity and that would be suitable for placement using shotcrete methods. This material could be applied in deep, hot mines where mine drifts must be insulated. Its use would decrease mine refrigeration needs and reduce energy costs.

Jan 1, 1994

By Joseph Grumer

In addition to nine powder and gaseous extinguishants of propagating Pittsburgh seam coal dust-air explosions earlier evaluated,6 10 other powders have similarly been evaluated under like conditions such that wall quenching of the coal dust-air flames was virtually absent and the dust concentration was temporally and spatially uniform to within about ±5 percent. None of the newly examined extinguishants was better than Purple-K (potassium bicarbonate); the 10 of this report are anhydrite (calcium sulfate), monobasic (4 types) and dibasic ammonium phosphate, natural and synthetic cryolite (sodium fluoalumi-nate), sodium sulfate, and tricalcium phosphate. Except for anhydrite, sodium sulfate, tricalcium phosphate, and the cryolites, these materials were about equally effective, when present in relatively low concentrations (weight-percent of the coal dust-extinguishant mixture). The maximum oxygen concentration for the extinguishment of otherwise uninhibited coal dust explosions and the influence of coal dust particle size and the volatile content of the coal were also explored. For the present, the choice of the inhibitor among the good ones evaluated is not as critical as the system to be used to deploy the extinguishant against a coal dust explosion.

Jan 1, 1973

By Guy A. Johnson

This Bureau of Mines report summarizes the results of efforts to develop reasonably priced, reliable mine shaft fire and smoke protection hardware for metal and nonmetal mines. The hardware was incorporated into a viable prototype system that would minimize fire and smoke hazards. The design of the system had to be sufficiently flexible to be utilized in a wide variety of metal and nonmetal mine shaft and shaft station configurations. As a result of long-term, rugged field tests, an improved (second generation) system was developed. The hardware is now commercially available.

Jan 1, 1978

By Thomas C. Miller, Rudolph Sporcic

A relatively simple and inexpensive encapsulated hydraulic device has been developed by the Bureau of Mines to facilitate study of coal bumps , and to measure pressure changes in a coalbed as it is subjected to roof loading during mining . Construction of the device and application techniques are described . Preliminary feasibility tests in the laboratory and field indicate that the device responds satisfactorily to pressure changes in coal created by roof loading .

Jan 1, 1964

Volumetric measures [ ]

Jan 1, 1962

By R. V. Ramani, R. Stefanko, G. W. Luxbacher

TEST DECK - AITIHETER SURVEY WITHOUT ALTIMETER TEUPERATURE CORRECTION DATA INPUT

Jan 1, 1977

Jul 1, 2003