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These proceedings consist of an overview of the underground metal and nonmetal mina fire protection research currently being conducted by the Bureau of Mines. The following papers address the areas of prompt, reliable fire detection, fire planning and warning, fire suppression, and personnel protection. Selected topics are included here that cover fire protection systems for shafts, underground fueling areas, and mobile underground mining equipment; spontaneous combustion, improved stench, and product-of-combustion fire warning systems; computer-aided ventilation modeling; fire doors; and an investigation of fire hazards in mine timbers. The projects described provide a current documentation of problems being addressed.

Jan 1, 1981

A new horizontal borehole packer for use in coal beds has been developed. This packer utilizes a principal of operation which has not previously been used. The resulting packer is less costly to purchase, can be easily repaired in the field with inexpensive expendable parts. This report describes the development and testing of the new packer and the evaluation of commercially available packers.

Jan 1, 1971

By R. R. Falier, W. E. Rice

"PURPOSE OF REPORTThis paper presents the results of a series of tests made by the U. S. Bureau of Mines in cooperation with The Ohio State University Engineering Experiment Station as part of an investigation on the use of fuel in kilns.This report is preliminary and gives only enough of the test data to illustrate results and show the reasons for the successes and failures of the method of firing investigated; fuller details will be included in the final report.PERSONNEL FOR TESTSThe investigation is conducted under supervision of P. Nicholls, supervising fuel engineer, of the United States Bureau of Mines, and G. A. Bole, research professor, of The Ohio State University. These tests were made under direction of W. E. Rice, associate fuel engineer, assisted by R. R. Faller, assistant fuel engineer, of the United States Bureau of Mines; H. C. Harrison, senior research engineer (until October 1, 1930), C. R. Austin, senior research engineer (since October 1, 1930), and H. K. Van Sohoick, junior research engineer, of The Ohio State University. M. J. Rice, field engineer, represented the manufacturer of the stoker.PURPOSE OF INVESTIGATIONThe general aim of the investigation is to develop more economical methods of using fuel in kilns and to improve the over—all efficiency of the process of firing by methods that will produce ware of better quality. One phase of this investigation is the burning of coal on an automatic stoker to gain the advantages of control, constant rate of application of heat, and ability to burn cheaper coal than can be used in the hand—fired furnaces of kilns. It a stoker in to be used it is desirable that the coot of the installation should be low, the control of operation simple, and the distribution of heat in the kiln as good or better than with hand firing. These desiderata were sought in the stoker and furnaces that were used for the tests described herein. The tests were made to determine whether it is feasible to fire a large kiln with a single stoker, whether the use of a single furnace simplifies control, and whether the admission of all the hot gam at the center of the kiln will give symmetrical distribution of heat."

Aug 1, 1931

By D. C. Fleck

Electrorefining yttrium from selected low-melting yttrium--base alloys is investigated, and various halide systems are studied as potential electrolytes for use in preparing low-oxygen yttrium by electrorefining unalloyed yttrium. Yttrium cathode products having significantly less metallic impurities than the anode materials were prepared from alloys containing nickel, iron, and manganese by electrorefining in LiCl-YC13 electrolytes at 900° to 1,000° C. Yttrium-copper and yttrium-magnesium alloys are not suitable as anode feed materials, An evaluation of chloride, fluoride, bromide, and mixed chloride-fluoride electrolytes showed that cathode products containing much less oxygen than the anode material can be obtained in the fluoride and mixed chloride-fluoride systems. Initial cathode current density has no apparent effect on the purity of the products obtained in both phases of the investigation.

Jan 1, 1973

By G. Asai

The purpose of this Bureau of Mines investigation was to determine the properties of arc-melted iron-chromium alloys ranging in chromium content from 12 to 50 wt.-pct. Alloys were prepared by consumable-electrode arc melting of electrodes composed of high-purity chromium and high-purity iron. Alloys were fabricated to rod and sheet, and the following data were obtained: Electrical resistivity, hardness, tensile strength, and impact strength at room temperature; and creep-rupture life at 650° C. (1,200° F.). As the chromium content of the annealed alloys varied from 12 to 50 pct., the properties varied as follows: The electrical resistivity increased proportionally from 41 to 53 microhm-cm,; the Rockwell hardness varied from A 38 to A 58; the tensile strength ranged from 52,000 to 96,000 p.s.i.; the impact strength of V-notched charpy specimens varied from 140 to 405 ft.-lb., and the 100-hour creep rupture life at 1,200° F. varied from 5,000 to 16,000 p.s.i.

Jan 1, 1962

By Michael G. Zabetakis

Vaporization of a solvent into an airstream at temperatures above the flash point of the solvent is hazardous if vapor is liberated at a rate that is sufficient to produce a flammable mixture. In may operations, the formation of such a mixture is prevented by rapid diluton of the vapors with air. The minimum air requirements for the dilution process are determined by the composition of the lower limit mixture at the temperature and pressure of interest. Because limits of flammability cannot always be calculated with sufficient accuracy for a proposed operation, they .rust often be determined experimentally. The present Bureau of Mines investigation was prompted by an application in which the lower limits of flammability of a number of solvent mixtures were required over a range of temperatures at atmospheric pressure. These limits were to be used along with available solvent-vaporization-rate data to establish minimum airflow rates needed to prevent the formation of flammable mixtures in an industrial process. Lower limits of flammability were determined for a number of mixtures containing methyl ethyl ketone, tetrahydrofuran, toluene, ethyl alcohol, and ethyl acetate in dry air-at atmospheric pressure and temperatures between 16° and 200° C. The experimental values were found to be in good agreement at with those predicted by Le Chatelier's law; variations with temperature were in fair agreement with those predicted by a modified Burgess-Wheeler law.

Jan 1, 1962

By Joseph M. Singer

This research project had two main objectives: (1) To identify the smoke limits of gaseous fuel-air mixtures and (2) to obtain and evaluate basic chemical information on the formation of smoke in very rich flames near the smoke limit. Such information would do much to establish the circumstances for car-bon deposition in gas appliances and in other types of combustors. Based on tests with ethylene and propane, these studies showed the following: 1. Smoke limits are related to the yellow-tip limits of the fuel. Previous research established sufficient data to permit prediction of yellow-tip limits on gas burners using a wide variety of fuels. The present study of smoke limits deals only with ethylene-air flames, but the concept that was developed is probably applicable to other fuels.

Jan 1, 1962

By James M. Baugher, Donald W. Conrad, William J. Wiehagen

This report describes a process for quickly developing information that is useful for skills training. The process is called job training analysis (JTA). Its main use is to structure skills training at the jobsite. JTA supports structured skills training by identifying the job duties, tasks, and steps and the reasons why those job components are important. The outcome of the JTA process is a worksheet—a training outline based on the knowledge and expertise of experienced workers. Time invested in developing a JTA will result in significantly more time saved when it is used appropriately by skilled trainers. Like a roadmap, JTA saves time and energy. Experimental work at several mine sites helped document, refine, and validate the JTA process. JTAs for two mining jobs—roof bolting and lift truck operation—at two different mine sites are used to illustrate some of the concepts and the specific JTA process described in this report. The work at these two sites was influenced by cooperative work between the Mine Safety and Health Administration (MSHA) and the National Institute for Occupational Safety and Health (NIOSH) at several other mine sites and prior collaborative work with the U.S. Navy. The mining JTA process is grounded within the military research on the design of instructional systems. MSHA and NIOSH worked to simplify and apply the military training development model for mining industry use through collaborative work at several mine sites. The JTA process involves three activities: (1) planning, (2) a 1- to 3-day workshop where the JTA is developed using facilitated work with subject-matter experts, and (3) followup. Guidelines and considerations for each of these activities are included. Results indicate that the JTA process has been well received and valued by mining industry participants. It blends aspects of health and safety, production, maintenance, and crew coordination.

Jan 8, 2006

By Patrick A. Hamilton

This Bureau of Mines report delineates the coal reserve base of anthracite, bituminous and subbituminous coals, and lignite, by mining method and sulfur content, for coal-bearing States west of the Mississippi River. The parameters used to establish the reserve base definition are the result of a joint agreement by the Federal Bureau of Mines and the U.S. Geological Survey. The reserve base of low-sulfur coal, =10 percent sulfur, is 167,324.5 million tons; medium-sulfur coal, 1.1-3.0 percent sulfur, is 37,531.5 million tons; and high-sulfur coal, >3.0 percent sulfur, is 11,244.1 million tons. The reserve base of coal with an unknown sulfur level is 18,323.0 million tons. The percentages of deep and strippable coal are 56 percent and 44 percent, respectively. The basis for reserve base estimates and analytical data for this report was the Fuels Availability System, a Bureau of Mines data bank containing numerous data tin fossil fuels. Information contained in the system was obtained from publications of the Bureau of Mines, U.S. Geological Survey, State agencies, private publications, and company data.

Jan 1, 1975

By William J. Karwoski

To improve rock-burst control in deep vein mining, a field demonstration has been carried out by the Bureau of Mines to test a new rock-burst control concept--rock preconditioning in advance of mining. The procedure is to fracture the major rock-burst-prone zone during the development of each level before production mining. This allows initial mining to begin in a preconditioned zone and later mining from the level below to end in a prefractured or preconditioned pillar zone that is relatively burst-free. This full-scale field demonstration was carried out On the 7700 level of the Hecla Mining Co.'s Star-Morning mine. An expected burst-prone zone along the main vein between 7 and 10 crosscuts, some 250 feet long by 40 feet above and below the level, was preconditioned by blasting a fanlike ring of drilled holes from each crosscut. The drill holes, up to 100 feet long and 4 inches in diameter, were loaded with high explosives and shot. About 4,550 feet of drilling and 9,000 pounds of explosives were involved in the effort. Comparison of preshot and postshot data from monitoring instrumentation indicated that the blasting did fracture the rock in the planned zone and did result in an immediate stress decrease and softening of rock. The field data compared favorably with predicted results from a finite-element computer model simulation of the destressing. Based on observations made during mining and on the data from the Hecla rock-burst monitoring system, there is no doubt that this preconditioning in advance of mining demonstration resulted in much-improved rock-burst control during first-floor mining. It was also concluded that preconditioning the vein was more effective than preconditioning the wall rock.

Jan 1, 1979

By Peter G. Kovalchik, Rudy J. Matetic, Susan B. Bealko, Adam K. Smith

Overexposure to noise remains a widespread and serious health hazard in the U.S. service providing and goods producing industries. Excessive noise can lead to poor verbal communication and reduce the ability to recognize warning signals. These dangerous work conditions can also cause stress and fatigue. Occupational hearing loss is a permanent illness, with no recovery currently possible. Method: National Institute for Occupational Safety and Health (NIOSH) has recognized Noise Induced Hearing Loss (NIHL) as one of the ten leading work related diseases and injuries in the United States, and has emphasized its importance as one of the critical areas expressed in the National Occupational Research Agenda. Results: One of the most serious noise problems in the goods producing industries is the operation of continuous mining machines during underground coal mining. In order to minimize occupational hearing loss, noise hazards are “designed out” early in the design process. NIOSH is leading a national initiative called Prevention through Design (PTD) to promote this concept. This paper describes the quiet by design approach of a noise control that reduced noise exposures of continuous mining machine operators by 3dB(A) using the four functional areas of PTD, namely Practice, Policy, Research, and Education.

The Bureau of Mines, in an effort to improve resource conservation, mine planning and development, is currently investigating the loading behavior of pillars in multiple-seam developments. The simultaneous mining of two or more coalbeds may cause instability between room-and-pillar operations resulting in an interaction known as pillar load transfer. Although pillars may be adequately designed for single-seam mining, the development of a second seam may complicate loading conditions in both operations. If pillars are not adequately designed to contend with this load transfer, failure of the mine structure may result. To improve multiple-seam development and pillar design, the Bureau studied the loading characteristics of pillars in three separate multiple-seam operations. In all three cases, instrumented pillars recorded increasing pressure after development of the second seam. Increases in the average pillar pressure ranged from 7 to 110 pct over predicted overburden loads. An analysis of pillar loading before and after second-seam mining indicates that the ratio of overburden to innerburden thickness is a critical factor influencing load transfer. Based on this relationship, safety factors for case study pillars are calculated and alternative design considerations are discussed.

Jan 1, 1988

By Charles H. Etheridge

A new filter cassette is described which can be used with Coal Mine Dust Personal Sampler Units (CFR, Title 30, Part 74). The sealed cassette design reduces the chances of sample loss due to reverse flushing, impact or cassette opening. The filter capsule weight is approximately 400 milligrams and is stable for at least one year in storage. The alpha quartz content of the filter element is less than 5 nanograms per square millimeter of surface. The cassette is designed to be used with a new sampling head. The manufacturing costs of the new cassette will require an increase of approximately 30% in the selling price.

Jan 1, 1978

By Shih-Chi Chang

[An exploratory research is done on untreated coal 1v- using&apos; x-ray crnctinn techniques. Comparison is made on diffraction data before And pct Pr n-tiAne is pressurized (n the coal samples. Although, only ? qualificative -1; t s obtained, the FoIIowing Statement r :&apos; n untreated teal seem- There are other materials in cost. They are accumilated in !e ,r rc r, cin? the microseoric layered structure of coal. 7"P partial graph r :r a&apos; o., «&apos; the i&apos;pr1 cart o ! in cna1 assumes varclor, r,rie&apos;,r: r in&apos;is. R nr ?-&apos;c,.r1&apos;ed I n coal is helm ;n the micrornre s&apos;??ste^ o&apos; c, .:l an&apos; t rr i, ,o <.~i:&apos;epee of Ion(4inc to carton h« x-ray tit If raction me.:SUr&apos;rientq. :t?e me r &apos; nP in r^icropores assumes no structure themselves at room tempera¬FLre. ;inally, some of the other materials in coal are in the form of }vrlrited crystallites and they have anisotropic pro&apos;th hnt&apos;1? in the lavers.]

Jan 1, 2012

By Richard A. Allwes

The Bureau of Mines conducted an in-mine case study on two consecutive three-entry gate road systems designed in accordance with the stiff-yield pillar design concept. This Bureau study was conducted in order to further develop technology that will improve the health and safety aspects of longwall mining. Support loading and strata activity were monitored to determine the effects of retreat longwall mining on the gate road ground control system. Analyses of pillar stress and roof bolt loading histories revealed that headgate roof support elements ex-perienced cumulative loading throughout the life of the longwall panel. Tailgate pillar loadings had significantly different histories from the loading histories of the headgate pillars. Stress relief occurred in the tailgate pillars following the passage of the longwall face. More-over, the stiff-yield pillar design, with the abutment pillar placed adjacent to the working panel when part of the headgate system, provided effective ground control in that no major roof falls or roof problems were experienced in the headgate or tailgate systems during longwall mining.

Jan 1, 1985

These proceedings consist of papers presented at a Bureau of Mines Technology Transfer Seminar in September 1981 for the purpose of disseminating recent advances in mining technology in the area of premining research. The introduction and descriptive papers discuss techniques and instrumentation used in premining research for metal and nonmetal mining and shaft design and borehole control for premine planning.

Jan 1, 1982

The panic bars (and associated linkages and electrical circuitry) that are defined in this document are a machine operator-actuated control for the emergency deenergization of the tram motors on self-propelled, electric and diesel face equipment; including haulage equipment such as shuttle cars. There are nine basic types of panic bars (and several variations) that are recommended in this document, but all of the panic bars are characteristically of the "fire door" type that is frequently encountered on outside exit doors of many public and some commercial buildings. It is also the intent of the following panic bar designs that, when emergency brakes are added to the face equipment machinery for which they are required, that they be designed and hooked up so that actuation of the panic bar will result in automatic application of the emergency brakes (immediately following the deenergization of the tram motors). The following panic bar design requirements are a restatement of the proposed requirements defined in the Federal Register, requirements cited in &apos;Guidelines for the Design and Installation of Devices for Deenergization of Self-Propelled Electric Face Equipment/ Automatic Emergency Brakes" by C. E. Lester and J. D. Greenhalgh of MESA, and Bendix recommendations that were formulated as a result of discussions with personnel at the various machine manufacturers and underground coal mines that we surveyed, discussions with G. L. Judy (our consultant), etc:

Jan 1, 1974

By Liane L. M. Kacinuck

This U.S. Bureau of Mines publication is intended to provide mining industry representatives and regulatory authorities with a reference package dealing with studies on hydrology and underground mine subsidence. An annotated bibliography and a list of additional sources are given and represent references published prior to June 1993. Ninety-two references ware identified and 72 obtained for assessment. Annotating the references included evaluating the study methodology and summarizing the basic results. The references are also compiled based on geographic location to aid the user in identifying articles of particular interest.

Jan 1, 1994

By Lawrence J. Froisland

To aid in minimizing adverse environmental impacts of mining and mineral processing, the Bureau of Mines studied changes in soil characteristics in topsoil stockpiled during mining operations. Topsoil stockpiles in arid areas of New Mexico, Utah, and Wyoming were sampled over a 1- to 8-yr period to determine any changes in physical, chemical, or biological parameters in the top 15 ft of soil. Parameters examined in this study included soil moisture, pH, electrical conductivity, and cation exchange capacity; total nitrogen, organic carbon, carbon to nitrogen ratio, extractable potassium, and soluble phosphorus levels in the soil; general levels of bacteria activity in the soil; and productivity of the soil as measured by shoot yield in growth tests. Data were analyzed by multiple linear regression to determine possible effects of stockpile age and depth. Bacteria population counts, used as an indicator of goner l bacterial activity, was the only parameter found to be significantly correlated with stockpile age and depth at more than one site. Bacterial activity increased with depth at the two sites where it was measured. Activity increased with age at one site and decreased with age at the second. Significant changes in soil pH, electrical conductivity, and moisture were significantly correlated with stockpile age and depth at single sites. This study did not show significant, consistent deterioration in soil characteristics or growth yield of topsoil stored in stockpiles.

Jan 1, 1987

By E. P. Youngman

This paper presents one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative, to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the mining laws of British Guiana has been prepared from the best available sources in Washington and is, released subject to amplification and correction, if necessary, by United States foreign-service officials. INTRODUCTION The sources of information available in the preparation of this paper are the following: 1. The Crown lands ordinance, No. 32 of 1903, September 26, 1903.

Jan 1, 1934