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To develop a business case that promotes adoption of noise controls by reducing barriers to industry acceptance and enhancing drivers that foster their implementation. Background Over 75% of the U.S. mining workforce is exposed to hazardous noise, putting them at risk of noise-induced hearing loss (NIHL). Consequently, coal miners suffer high rates of hearing impairment that increase to 70%-90% by retirement age. To address the noise problem for coal miners, researchers from the National Institute for Occupational Safety and Health (NIOSH) first determined that the continuous mining machine (CMM) ranked first among machines associated with reported coal noise overexposures. Further studies found that most CMM noise is generated by three component systems on the machine: dust collection, cutting, and conveying. Of these systems, the on-board chain conveyor was found to be a dominant noise source. Noise generated by the conveying system was addressed through the development of a urethane-coated flight bar chain. The coated chain, shown in Figure 1, has demonstrated an 8-hour time-weighted average (TWA) reduction of operator exposure by 3 dB(A). It has since been accepted by the Mine Safety and Health Administration (MSHA) as a "technologically achievable" noise control for CMM operators who are exposed to noise that exceeds the MSHA permissible exposure level. Having demonstrated the noise reduction performance of the coated chain, NIOSH has assembled information into a business case that can be used by operations considering adopting the chain at their worksite.

Dec 1, 2009

By C. J. Walker

The ever-increasing use off natural underground formations for storing natural gas has focused attention on the behavior of such storage formations under varying operating conditions. The need for a means of evaluating in¬dividual wells and groups of wells has become manifest. It is essential that industry and others be able to determine the rates of flow that can be ex¬pected from a given well or group of wells under different conditions and to ascertain whether certain wells are deteriorating. Such questions need more exact answers now than ever before because of the vital role underground gas storage plays in the industrial and domestic consumption of natural gas. The Bureau of Mines--in cooperation with the American Gas Association--has main¬tained an active interest in gas-well testing because of the implications of such test procedures on the consumption and efficient production of natural gas. A basis for testing gas wells was provided by the back-pressure method of Rawlins and Schellhardt (12).4/ They showed that for normal gas wells there is a consistent relationship between rates of delivery of gas and corresponding pressures when the formation pressures are used as the basis of interpretation, The equation for this relationship is as follows: Q = C (Pf2 - Ps2)n where; Q = rate of flow, generally expressed in cubic feet per 24 hours. C = a coefficient.

Jan 1, 1960

By William H. Pomroy

Spontaneous combustion fires involving high-sulfide-content ores are a relatively infrequent yet serious safety hazard in mining. They are also the cause of lengthy mine shutdowns because they typically occur in areas of a mine where abundant fuel material is present but which are inaccessible for fire fighting. This Bureau of Mines report describes research to design, fabricate, and test in the laboratory and field a system that warns of spontaneous combustion fires in metal mines. Overall performance of the detection system was found to be satisfactory, in that the system was capable of reliably detecting low levels of combustion products believed to indicate the preflaming stage of spontaneous combustion in metal mines. Installation of similar systems in mines with a high risk of spontaneous combustion is recommended. Principal operating problems and recommended corrective actions are also discussed.

Jan 1, 1987

By Robert J. Anderso

Few elements have received more attention and developed greater interest in the last ten years than titanium. The substantially pure metal has been din...ie. cult to isolate, and so far has been little employed oommercially, but the use af alloys and chemical compounds of titanium has increased markedly in recent years. The earlier attempts at preparing pure titanium resulted in various impure forme which, from their metallic appearance, were always mistaken for the metal. Hunter in 1910 isolated pure titanium by the reduction of titanium tetrachloride with sodium. This brief statement is issued by the Bureau of Mines in response to numerous inquiries which have been received concerning titanium. More complete in. formation on the metal may be had by consulting the referenpes appended. The Literature is voluminous and only the more important references are Riven. It has been drawn upon freely in preparing this report; also information was supplied by M. g. Hunter, Arthur Braid, M 1. Schmid, C. M. Johnson, N. B. Hoffman, and de Courny Browne. The pioneer investigator in titanium is A. IL Rossi.

Oct 1, 1922

By W. S. Landers

This report presents a study by the Federal Bureau of Mines of technical factors related to the production of special carbon and tar from selected Wyoming coals. Certain Wyoming high-volatile bituminous and subbituminous coals were processed in bench-scale apparatus to determine potential carbonization yields and in pilot plant retorts to produce sufficient char and tar for testing. These tests have shown that a critical selection of coal is necessary when the coal is processed for a specialized carbon. Generally high yields of tar are obtained from low-temperature carbonization of Wyoming high-volatile bituminous and subbituminous coals, and the yield of tar usually increases with increase in rank within this range of coals. The production and evaluation of industrial carbons from Wyoming coals by using pilot plant and bench-scale techniques is part of the continuous program of upgrading western coals. It has been found that: 1. Most Wyoming coals are nonagglomerating and may be carbonized in fluidized systems. Chars produced in pilot plant retorts at low temperatures contain about 17 to 23 pct, residual volatile matter and are easily ignited. These chars appear suitable as power plant fuel. The tar-plus-light-oil yields range from 14 to 40 gal./ton of raw coal processed. 2. Wyoming high-volatile coals produce a slightly smaller and somewhat weaker coke than currently mined Western United States high-volatile coals used commercially as blending stock in metallurgical coke production.

Jan 1, 1961

By Irving Hartmann, John Nagy

"The pressures produced by dust explosions are frequently so great and are developed so rapidly that widespread destruction of manufacturing equipment and buildings results. Experimental data on maximum pressures and rates of pressure rise produced in a closed vessel by numerous metal powders and by dusts used in the plastics industry were published in two previous Bureau of Mines papers.4/5/One means for reducing structural damage is provision in the enclosing walls and/or roof of rapidly opening explosion-relieving devices or relief vents through which the pressure of an incipient dust explosion can be quickly dissipated. The vents can be simply unrestricted or free openings: hinged or pivoted sash which swing outward at a predetermined internal pressure; fixed sash, with light wall anchorages; scored glass panes; light wall panels; monitors or skylights; poppet-type vent closures; paper, metal foil, or other diaphragms that burst at low pressures; pull-out diaphragms, or other similar arrangements.The use of pressure-relief vents is recommended in the dust-explosion codes of the rational Fire Protection Association,6/ and recently a special committee on explosion venting has been organized. However, technical data on which the design and distribution of relief vents can be based are meager. An experimental study on venting grain-dust and cornstarch explosions was made by the Bureau of Chemistry and Soils, United States Department of Agriculture.7/ Tests on cork fines, cinnamon, starch, barley dust, and a phenolic plastic were made in a laboratory-scale (0.1-cubic-foot) apparatus by the engineering department of the Factory Insurance Association.8/ A study on the venting of explosions of acetone-air mixtures was made by the Bureau of Mines.9/The object of the present investigation is to extend the limited knowledge on the effectiveness of pressure-relief vents of different types, shapes, and sizes. The aim is to determine the venting requirements in equipment and structures of various dimensions and shapes for dusts of widely different explosive properties. On the basis of such accumulated information, together with theoretical considerations, it is hoped that ultimately it will be possible to recommend correct venting for most operations in which a dust-explosion hazard exists."

May 1, 1946

By J. F. Barkley

Under the procedure of the American Standards Association, with the American Society for Testing Materials as sponsor, the Sectional Committee on Classification of Coals has arrived at the classification of coals by rank as shown in Table 14/. The standard explains the term "agglomerating" used for classification under physical properties, as follows: Agglomerating Index. - Coals which in the volatile-matter determination produce either an agglomerate button that will support a 500-g weight without pulverizing, or a button showing swelling or cell structure, shall be considered agglomerating from the standpoint of classification.***. Pending the adoption of a method by the American Society for Testing Materials, the coke-button grading test5,/ afforded by the examination of the residue in the platinum crucible incident to the volatile matter determination, shall be used.

Jan 1, 1937

By W. D. Dietzman

This Bureau of Mines report presents a profitability analysis of producing crude oil by waterflooding. Included are the estimated costs of installation of water injection and producing equipment for waterfloods at 2,000 and 4,000 feet and the estimated annual operational expenses for each in west Texas. Using these cost estimates as a base for selecting a range of costs that are indicative of producing crude oil by waterflooding, a simulation technique was derived for determining the profitability under various conditions. Because of the large number of combinations of variables used in this study, a high-speed digital computer was utilized for the calculations. The variables include operational expenses, capitalized costs, price of the oil, annual production, and leasehold acquisition cost. The results obtained from the simulations are presented Fn the appendix. In addition, a nomographical approach was chosen for presentation of the profitability. Five nomographs are presented that can be used for fast estimation of the discounted cash flow (DCF) rate of return that might be expected from a prospective or active operation under various sets of assumed conditions.

Jan 1, 1974

By G. S. Scott

[The Duretiu of Kinen, as :) pr<r"Yof its :;encr:rL propan clealini: with the causes, behavior, n.ncl tor-trol of o1:t1?;.?cite-mine fires, hns investic:&apos;lte3 I varionr. Te:.nr, for Je tec tin:: iccj.r)ic:~ t he;, tint; :,:.zqdergro-.:rid and of <~e termining the trend of the hen tir..: once -I i&apos;i re j 7 knnm tr, he nrcsc~t.]

Jan 1, 1938

By G. S. Scott

[The Duretiu of Kinen, as :) pr<r"Yof its :;encr:rL propan clealini: with the causes, behavior, n.ncl tor-trol of o1:t1?;.?cite-mine fires, hns investic:&apos;lte3 I varionr. Te:.nr, for Je tec tin:: iccj.r)ic:~ t he;, tint; :,:.zqdergro-.:rid and of <~e termining the trend of the hen tir..: once -I i&apos;i re j 7 knnm tr, he nrcsc~t.]

Jan 1, 1938

By R. Clark Lantz, Charles Stanley, David E. Hinton

Morphometric examination of lung alterations following exposure to toxic and pathogenic substances is invaluable in detecting subtle changes which might otherwise be overlooked. Results, from evaluation of initial structural alterations, support and guide subsequent nonmorphological techniques and, when coupled appropriately, can lead to a better understanding of the pathogenesis of a disease. Morphometry is a technique which can be used to determine, quantitatively, the site, extent, development, and progression of a disease state. Determination of the extent of tissue and cellular involvement in the response to inhalation of silica has been performed in order to gain a better understanding of the development of fibrosis following inhalation of this toxicant. In addition, since silica has been postulated as one of the important pathogenic minerals in coal mine dust' it is important to understand the lung tissue response to silica prior to evaluating the effects of inhaled coal mine dusts. Male Syrian golden hamsters were placed in Hazelton 1000 inhalation chambers and were exposed to either filtered air (controls, n = 24) or filtered air plus 30 mg!m3 silica (Min-U-Si110,95%ofparticles < 5 um,n =24)for16hours per day, five days per week, for two weeks. Animals were returned to the animal quarters prior to subsequent tissue processing at 1, 4, and 12 weeks following exposure. This schedule was designed to allow time for the development of fibrosis. Lungs were fixed by intratracheal perfusion of ½ strength Karnovsky's fixative at a pressure of 20 cm H20 and tissues were taken for embedment and analysis at the light level. Determination of site, extent, and development of alterations was performed using a multitiered approach. Changes in large structures (airways, blood vessels) was determined prior to evaluation of changes at the septal tissue level. Data will be presented outlining the progression of changes. Results indicate the usefulness of morphometric analysis of lungs following inhalation of toxic substances in quantitatively defining the structural alterations.

Mar 1, 1989

By E. J. Harris

Data obtained from mine ventilation pressure and quantity surveys are required to accurately diagnose ventilation problems, project future air quantity needs, and to locate conditions adversely affecting the efficiency of a mine ventilation system. A method for making mine ventilation pressure surveys with aneroid altimeters was presented in Bureau of Mines Information Circular 7809, and a description of field calculation technique is presented. This report supplements Information Circular 7809 by developing the information obtained during a mine ventilation pressure survey into a single equation suitable, with appropriate modification, for use with desk-top calculators and digital computers. The equation can be used to calculate the ventilation pres sure from the base station to any underground station, or between any two underground stations, and can be programed for semiautomatic sequential calculation using a desk-top calculator. An example of application to a programed desk-top calculator is provided in the appendix.

Jan 1, 1973

By W. W. Graff

This paper describing the mining practices at Mine, No. 4 on the Marquette range, Michigan, is one of a series of articles on mining methods and practices in various mining districts in the United States. Mire No. 4 is located in the Swanzy district, in the southern end of the Marquette range, about 3 miles from Gwinn, Mich. The Swanzy district is an isolated ore-bearing formation, and Mine No. 4 is at the extreme southeastern end.

Jan 1, 1930

By W. P. Yang, L. B. Berger, G. W. Jones

"Any burning carbonaceous material, unless supplied with enough oxygen for complete combustion, will liberate carbon monoxide. Since tobacco in its many different forms consists largely of carbonaceous material, and duo to the conditions under which it is smoked (burned), carbon monoxide should be liberated. That this is true has been shown by Armstrong.***** who found that undiluted smoke from cigars contained in some tests more than 3.00 per cent carbon monoxide, the amount present depending upon the size and closeness of packing of the tobacco during manufacture and on the rate of burning.****** Cigarets gave much less CO, varying from 0.06 to 1.40 per cent. The rate of consumption and carbon content of the tobacco are not g.ven, so that a correlation of the values reported to conditions in closed spaces where people might be assembled are difficult, if not impossible.The Bureau of Mines is interested in the general question of carbon-monoxide hazards from tobacco smoke, mainly with regard to mine ventilation. In non-gaseous mines, especially metal mines, the question arises, whether, if groups of miners are permitted to smoke while working at unventilated faces or entries, would the accumulation of tobacco smoke in these places create an' additional hazards the to carbon-monoxide poisoning. The results should, in addition be of general interest in connection with ventilation of building and inclosed places where people may be assembled and smoking is permitted. The investigation described in this report was made with the above idea in view."

Oct 1, 1923

By E. Wittenau

This paper describing the concentrator practice of the Copper Queen Branch of the Phelps Dodge Corporation at Bisbee, Ariz., is one of a series of papers on milling methods and costs being prepared by the United States Bureau of Mines. The Copper Queen Concentrator treats 4,000 tons of copper ore daily by preferential flotation, whereby the copper sulphides are floated and considerable iron pyrite is depressed. During 1929 the heads to the concentrator averaged 2.15 per pent of copper, the recovery was 91.32 per cent of the total copper, and the concentrates produced contained 12.92 per cent of copper.

Jan 1, 1931

By R. V. Higgins

This report presents the results of a study of gas injection in the Upper and Lower Terminal zones in fault block VB and in the Upper Terminal zone in fault block VI, Wilmington field, California. This report is based on data obtained to January 1956. Earlier studies of gas injection in other California fields have been reported .3/ The Upper and Lower Terminal zones, fault block VB, have been producing oil since 1945 and the Upper Terminal zone, fault block VI, since 1948. Before starting the gas-injection project, the expansion of dissolved gas was the principal mechanism moving the oil to the wells. Gravity drainage and an edgewater drive also have contributed to the movement of the oil to the wells. When the gas injection was begun, the reservoir pressure and the oil production had declined appreciably. Gas injection was started in the Upper and Lower Terminal zones, fault block VB, in May 1953 and in the Upper Terminal zone, fault block VI, in October 1953.

Jan 1, 1957

By Paul V. Mullins

Review and evaluation of all available data on the vapor pressure of car-bon dioxide at the ice point, including previously unpublished results obtained by the Bureau of Mines, are presented. Suggested corrections and adjustments to all the data yield an average value of 26,136.4 mm mercury. Indicated agreement is within plus 1 part in 8,000 to minus 1 part in 11,000. A novel pressure bomb in which a sample of pure carbon dioxide is placed and sealed by a diaphragm fluid separator and its use as a reference pressure standard for extended and repeated use in the calibration of deadweight gages is described.

Jan 1, 1966

By B. K. Shibler, K. C. Vincent, W. W. Agey

"INTRODUCTION As a part of the investigation of domestic manganese deposits, examining engineers of the Bureau of Mines collected samples of ore from three from three properties in the general vicinity of Tracy, Calif.The Buckeye mine is 23 miles of Tracy, just inside the northeast boundary of Stanislaus County. The mine is owned by K.O. Winship estate of San Francisco and is leased by Verner Allen, also of San Francisco.The ore is principally manganese carbonate occurring in interbedded layers in white chert, with the original,carbonate mineral altered in place. Four samples, representing four types of ore, were submitted, as follows: A, black oxide; B, pink carbonate; C, gray carbonate.The Wilfred Murphy property (also known as the Murmac claims) is approximately 30 airline miles south of Tracy. The property can be reached by road from either Livermore or Patterson and is on the divide separating Santa Clara and Stanislaua Counties Calif. The ore occurs in lenses along a white-chert formation. A 2-ton sample of ore for testing was taken from a dump accumulated from assessment and development work. The Ladd mine, 13 miles from Tracy in San Joaquin County is owned by Pat J. Connolly of Tracy and is leased by Mack C. Lake of San Francisco. The ore is essentially a chert impregnated with manganese oxides and the association is therefore exceedingly intimate and complex. Samples from each of the three adit levels of the mine were submitted for ore-dressing study.As the samples differed widely in physical character and response to ore-dressing methods of treatment, beneficiation of ores from each property was considered as a separate problem. Hence results of the investigations will be prescribed in separate sections of this report."

Nov 1, 1947

By Charles Vaught, Richard S. Fowkes, Ronald S. Conti, Barbara Fotta, William J. Wiehagen

The purpose of this study was to determine mine workers&apos; state of fire-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers &apos; responses are presented in this report, along with segments of narrative accounts, to profile miners&apos; fire-fighting capabilities. The data indicated that much variability exists from mine to mine and that there are several important changes operators may undertake in order to make miners better prepared to deal with fire underground: select appropriate sensors, establish and test a warning and communication protocol, construct a system capable of delivering hundreds of gallons of water per minute for sustained periods, institute formal fire preparedness audits, develop case studies of events that occur at an operation to use as teaching and assessment tools, and provide structured practice that can be incorporated into fire drills.

Jan 1, 1995

By W. W. Adams

This bulletin covers all mines in the United States that were operated in 1936 to produce metallic ores and all mines that were operated to produce nonmetallic minerals other than coal, stone, sand, gravel, or their products. Reports from mine operators revealed a better safety record for fatal accidents in 1936 than in any other year except 1934 during the 26 years for which annual surveys of accidents in the mineral industries of the United States have been conducted by the Bureau of Mines. On the other hand, the record for nonfatal injuries, although better in 1936 than in any year prior to 1930, was not as good as it was from 1930 to 1935, inclusive.

Jan 1, 1939