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By W. P. Yant

This report describes result of a study of the carbon monoxide and particulate matter in the air of the Holland, Tunnel and metropolitan New York made by the Bureau of Mines (which had participated in the development

Jan 1, 1941

By C. D. Litton

This Bureau of Mines report presents a set of guidelines for determining the distribution of product-of-combustion fire sensors in underground mines. Sensor spacing is defined in terms of sensor alarm threshold, ventilation flow rate, and mine entry dimensions. Sensor spacing guidelines are presented for detection of fires from two primary combustibles, coal and wood, which are common to the majority of underground mines. The guidelines are based on data from full-scale and intermediate-scale fire tests conducted by the Bureau of Mines.

Jan 1, 1983

By G. E. McElroy, A. S. Richardson

"Experiments in the determination of friction factors for fan-pipe installations were carried on in a Butte mine during the fall and winter of 1922-23, under a cooperative agreement between the Bureau of Mines and the Anaconda Ccpper Mining Co. The results have been summarized in a separate paper,*** and this report, which is one of several giving more detailed data, discusses the methods used and the application of the results to fan-pipe practice.The use of canvas and galvanized-iron pipe, 8 to 20 inches in diameter, with small fans, usually electrically driven blowers, is an important factor in the ventilation of metal mines and is increasing in coal mines and long tunnels. In the Matte district the standard installation is an electrically driven small blower fan and 8 to 16 inch canvas pipe.The application of available data on friction losses in sheet-metal pipe to mine installations was doubtful, and very little has been published on canvas pipe, except general statements that the friction looses are greater than in galvanized-iron pipe. Experiments by Weeks and others,**** who determined friction losses under laboratory conditions for a few typical materials used in mine equipment, supported the statements.In 1918, one of the authors (Richardson) conducted tests for the Anaconda Copper Mining Cc. on the friction losses in canvas-pipe systems and the beet type of centrifugal blower for use with such pipe lines. He obtained the average total resistance per unit of length in use, without reference to the variable conditions of the lines. The results were of great value in developing more efficient equipment for average service conditions, and indicated that average friction losses for the commercial canvas tubing then used by the company were equal to or lees than these given for galvanized-iron pipe. Later on, the particular canvas tested was discarded for a heavier and more service-material."

Oct 1, 1923

By R. H. Grau, S. B. Robertson, R. B. Krog

The National Institute for Occupational Safety and Health (NIOSH) has conducted research to improve the ventilation of large-opening mines. Large-opening mine ventilation is unique for the following reasons: (1) it is challenging to keep airflow velocities high enough to effectively remove or dilute airborne contaminants, (2) large air volumes can be moved through the mines with little static pressure drop, and (3) stoppings to direct ventilation airflows are costly to construct and maintain. The research results suggest that by incorporating ventilation planning into the mine planning process, using propeller fans, developing new stopping materials and construction methods, and using long pillars to eliminate crosscuts where possible, the ventilation of large-opening mines can be significantly improved. The ventilation improvements created by incorporating these various techniques into the ventilation plan will help reduce the exposure of mine workers to airborne contaminants in underground large-opening mines.

By Russell G. Warncke

"This report is based primarily on a study of safety conditions and practices followed in the coal mines of Japan. Not all of the coal fields in Japan were studied, but typical mines in the largest producing areas and a fair cross section of coal-mine-safety conditions observed during February to April 1948 are described.Information was obtained through investigations conducted in the mines, discussions with mine-management officials and representatives of labor unions of the various mines visited, and examination of records and statistics from the various offices of the Coal Board of the Ministry of Commerce and Industry and from the Coal Association of Japan. Statistical data covering the same subject, obtained from different sources, varied in many respects and apparently were reported inaccurately, but such discrepancies can be attributed to different methods of reporting and compiling statistics.It is difficult to correlate the high fatal and nonfatal injury rates that prevail in Japanese coal mines with the conditions observed in the mines. Virtually all mines visited were attempting to prevent accidents and explosions, by apparently following known safety precautions for the prevention thereof. Some commendable safety innovations were observed at several mines; they indicated that mine officials are giving thought and consideration to hazardous conditions that affect their particular mines.Naturally, the operating officials and management were anxious to impress the writer with their interest in accident prevention and safety. Operating officials were found to be receptive to safety and wore interested in formulating definite safety programs. Some nines had well-planned and well-organized safety programs, which, if put into effect, would contribute greatly toward reduction of accidents.The approach to safety in Japan is quite different from that in the United States, especially the concept of personal responsibility for accidents and the extent to which the individual should be protected against hazards. Management is responsible for providing and maintaining safe working conditions. Collaboration between management and worker, as understood in the United States, does not exist in Japan.Increase in accidents since the cessation of hostilities is the result of unsettled economic conditions in the coal industry, influx of inexperience workers, and breakdown of discipline among the miners, who have been organized into unions. Those unions are greatly influenced by ""leftist"" tendencies.It was observed that the Japanese mine worker is fatalistic by nature and has little, if any, noticable safety consciousness. The most urgent major requirements to reduce accidents in the coal mines are to train the worker in accident prevention and instruct him regarding the inherent hazards of his occupation.Revision of the mining laws would help to reduce accidents if the companies would comply with such laws and provide safer working places and if the workers would cooperate with management and observe and comply with such laws as are enacted for their protection."

Dec 1, 1949

This sheet explains your audiogram (hearing test) and gives some basic information about protecting your hearing. Keep it so you can refer to it later. What is an audiogram? • An audiogram is often called a “hearing test,” but there’s no pass or fail • It is a written record of your hearing levels • A series of audiograms can track changes in hearing over time • Your hearing threshold levels (the quietest sounds you can hear) are measured in decibels (dB) at different frequencies from low (500 Hz) to high (8000 Hz) Why should I get audiograms? • To measure your hearing ability • To identify hearing problems • To monitor success at maintaining your hearing • To see if noise exposure is affecting your hearing Do I have normal hearing? Compare your hearing threshold levels to this scale: -10 – 25dB Normal hearing 26 – 40 dB Mild loss 41 – 55 dB Moderate loss 56 – 70 dB Moderate/severe loss 71 – 90 dB Severe loss 91 – 100dB Profound loss [ ]

Jan 1, 2008

By H. D. Kline

This paper describes the methods of mining and washing brown iron are in 1957 at the Sawyer mine, leased by Wayne County Mining Co., and the Fore mine, leased by Four Mining Co., both in southern Missouri; it is one of a series prepared by the Federal Bureau of Mines on mining and milling methods and costs in various districts of the United States. The Sawyer mine is in Wayne County, about 10 miles north-northeast of Williamsville (fig. 1); the Fore mine is in Howell County, about 20 miles southwest of West Plains (fig. 2). Both are open-pit mines from which the crude are was upgraded by washing and hand-sorting to produce are of grade and quality suitable for sale to operators of iron and steel furnaces. The operations described are typical of many others that produce or have produced marketable brown iron are from small sedimentary deposits, several hundred of which outcrop on the crests or hill sides of southern Missouri (fig. 3). The 1957 production of marketable brown iron are by 40 separate operations in the southern part of the State was 281,427 wet long tons, valued at $1,637,243. Production from the Sawyer mine that year was 17,000 dry long tons of washed are, and from the Fore mine, 20,816 dry long tons.

Jan 1, 1960

To improve communication among Government, industry, and academic researchers in the field of thermodynamics, the Federal Bureau of Mines sponsored a Workshop on Techniques for Measurement of Thermodynamic Properties in August 1979. Participants at the workshop presented 33 papers on the subjects of temperature measurement and control, general calorimetric techniques, low-temperature calorimetry, high-temperature calorimetry, galvanic cells, ionic solutions, and heterogeneous phase equilibria. A special invited lecture was presented by E. F. Westrum, Jr., on the resolution of lattice heat capacity. This Information Circular comprises the proceedings of the workshop and includes the texts of papers presented and discussion by attendees.

Jan 1, 1981

By Galen H. Clevenger

Although there are exceptions, oxidized silver ores containing the higher oxides of manganese are generally refractory to hydrometallurgical methods of treatment. When these ores are of high enough grade they can be smelted; indeed, some rather low-grade ores of this type have been smelted at a profit because of their fluxing value. In the past, when these ores could not be smelted, they either were not treated or were treated at low efficiency, generally by cyanidation. The need for thorough investigation of the problem was therefore evident for some time before the writers began their research. The problem of treating manganese-silver ores seems to have been recognized first about 35 years ago by C. W. Goodale in applying pan amalgamation at Tombstone, Ariz. He attributed the low extraction of silver to the fouling of the mercury by manganese rather than to the presence of a refractory compound of manganese and silver. Although definite knowledge as to the cause of the poor extraction of silver was lacking, a more or less effective preliminary treatment, that is, a chloridizing roast, was applied.

Jan 1, 1925

By R. A. Franks, G. F. Friel, J. C. Edwards, L. Yuan

The reversal of smoke products-of-combustion (POC) from a mine fire was determined in a mine section with the airway connectivity of an electrical Wheatstone bridge. Four diesel-fuel fire experiments with fire heat-release rates between 504 and 771 kW were conducted in the Safety Research Coal Mine (SRCM) located at the National Institute for Occupational Safety and Health’s (NIOSH) Pittsburgh Research Laboratory (PRL). Smoke reversal propagated upwind from the fire with significant leakage into the upwind diagonal airway and without causing a complete reversal of airflow in the diagonal airway. A control measure consisting of a brattice suspended half entry height from the entry roof was determined to abate the smoke rollback. Computational fluid dynamics (CFD) analysis of the smoke movement agreed with the measurements.

By George L. Richert

The Minas de Matahambre is situated on the north coast of Cuba, in the Province of Pinar del Rio, approximately 150 miles west of Havana. This nine is the only producer of copper in Cuba, and has been worked for the past 15 years. In 1921 the property was affiliated with The American Metal Co., Ltd., and has been worked by them since that time under the direction of Mr. D. D. Homer, General Manager. Extracts from P. D. Wilson's ?Preliminary report on the geology at Minas de Matahambre? have been freely used in this report.

Jan 1, 1929

By P. B. Altringer

The Federal Bureau of Mines conducted a study to determine if residues from fractional distillation represent a potential source of mineral values. A literature review and discussions with tar sand specialists failed to disclose the mineralogical nature of residues remaining after bitumen extraction. To develop this information, pilot plant tar sand residues or toluene-cleaned tar sands from 23 deposits were examined. The nature of the residues was determined by standard mineralogical methods and the chemical compositions were determined by X-ray and ICP (inductively-coupled plasma spectroscopy). None of the sands or concentrates examined contained sufficient valuable minerals to be economically important.

Jan 1, 1982

By William F. Hahn

The Bureau Of Mines recognized the desireability of illuminating working places in trona mines. This report describes two illumination system designs, their demonstration and evaluation on a Jeffrey 120HR continuous mining machine in an active working trona mine in Wyoming.

Jan 1, 1980

By Hideo Ando, Yuka Satou, Tatsuya Ishitake

Whole-body vibration occurs when the body is supported on a surface which is vibrating. Occupational exposures to whole-body vibration mainly occurs in the transportation industry, but also in association with other industrial process. Epidemiological studies have frequently indicated an elevated health risk for the spine in workers exposed to whole-body vibration. With regarding to train or bus operators, a fall of drivers’ wakefulness level because of fatigue is often pointed out. This decrease in wakefulness results in an increase of the occurrence of accidents. However, a study of how whole-body vibration affects people's level of wakefulness has not been done. To test the hypothesis that exposure to whole-body vibration has a certain effects on level of wakefulness, the change of a subjective wakefulness level and changes of electroencephalogram (EEG) were observed under experimental exposure to short-term whole-body vibration. Methods Subjects are ten healthy male university students, with an average age of 20.7 ± 1.8 years old, and they are all nonsmokers. Using the equipment (CV-300, AKASHI) of whole-body vibration generator, we consider an exposure environment of actual driver work, so that set the frequency and the acceleration level as 10 Hz and 0.6ms-2 r.m.s.. The subjects were exposed to whole-body vibration in the seated position and exposure time was fixed for 12 minutes. Subjective wakefulness level was evaluated using the questionnaire of VASS (Visual Analog Sleepiness Scale) and KSS (The Kwansei Gakuin Sleepiness Scale). For the electroencephalogram (EEG) measurement, it was equipped with the electrodes based on the International ten-twenty electrode system (C3-A2, O1-A2, O2-A1). EEG activity in the alpha frequency band (8 – 12 Hz) is one of the most typical physiological indicator which represent the transition from wakefulness to sleepiness. AAT (Alpha Attenuation Test) which repeats three times each opened and closed eye for 1 minute was performed in a seating position with directions of the researcher in the beginning, in the middle and in the end of exposure to whole-body vibration. For analysis, power spectral analysis was conducted over the last 6 min of EEG, and wakefulness levels were defined as the ratio of mean alpha power during eyes closed versus eyes opened. The laboratory was kept at room temperature (21 ± 1.0 degrees C), humidity was 50 ± 5%, noise level was 63.6 dB (A) eq, and illumination 510 lx. Each experiment was started around 10:00 am to minimize the effect of biorhythm.

Jan 6, 2006

By Berk. A. A.

"INTRODUCTION Corrosion of sections of piping used in steam-heating systems is frequently regarded as unavoidable, and periodic replacement is provided. Surfaces exposed to newly condensed steam appear to be especially vulnerable to attack. As an added nuisance, solid products of the corrosion tend to accumulate, plugging return lines.The trouble is ascribed in the main to carbon dioxide and oxygen 3/ 4 / 5/ 6/ dissolved in the condensate. When oxygen is the principal factor, the corrosion usually is characterized by pitting. Carbon dioxide tend3 to cause an acidic condensate which dissolves the metal more uniformly and produces the familiar failure at threaded areas where the piping is relatively thin, and where high stress may tend to acceletate the attack. Carbon dioxide enters the system with the feedwater, generally in a combined form such as carbonates and bicarbonates. Oxygen enters both with the raw feedwater-and as air leaking into lines under partial vacuum. The larger central-heating plants have sought to reduce corrosion by eliminating these gases as much as possible. A smaller plant ordinarily lacks the equipment and technical supervision required for this purpose."

Jun 1, 1944

By Alfred V. C. Meyer

A Blastcorder4 was calibrated on the Bureau of Mines shaking table in the frequency range of 12 to 40 c.p.s. and in the amplitude range' of 0.25 to 1.0 g. The results of this calibration study show that in the frequency range of 12 to 30 c.p.s. the average accuracy of the Blastcorder is approximately ± 0.1 g.

Jan 1, 1962

By Roy C. Bartholomae, Jeffrey Shawn Peterson

1. INTRODUCTION In the early 1980s, the U.S. Department of the Interior’s Bureau of Mines Pittsburgh Research Center required that a large reverberation acoustic facility be constructed. This facility was designed to determine the sound power level emissions of mining equipment, especially continuous miners and jumbo drills. A contract for a conceptual design of a reverberation chamber was awarded to Wyle Laboratories of Huntsville, AL, which had extensive experience in the design, construction, and accreditation of acoustical reverberation chambers. The following standards were referenced as guidelines for the design of the chamber: ANSI S1.31-1980, “Precision Methods for the Determination of Sound Power Levels of Broadband Noise Sources in Reverberation Rooms” and ANSI S1.32-1980: “Precision Methods for the Determination of Sound Power Levels of Discrete-Frequency and Narrowband Noise Sources in Reverberation Rooms.” Specific requested criteria included that the room be large enough to accommodate typically large mining equipment and that there be adequate acoustical modal density in the frequency range of interest. It was also required that the room dimensions would support broadband acoustical measurements down to the 100 Hz third octave band. With the closing of the Bureau of Mines in 1996, this reverberation chamber lay dormant for a number of years. However, this facility is now part of the National Institute for Occupational Safety and Health’s (NIOSH’s) Pittsburgh Research Laboratory (PRL). One of NIOSH’s missions is to decrease noise induced hearing loss among the nation’s mineworkers. To this end, PRL researchers are refurbishing and instrumenting this reverberation chamber to facilitate assessment of the various engineering controls being developed to decrease the sound power level emissions of mining equipment. Early on, this work has sought to bring the chamber up to the level of ISO 3743-21 standard for engineering grade measurements for broad-band noise, with a longer range goal of improving the lab to meet the requirements of ISO 37412standard for broadband precision grade measurements. 2. DESIGN OF THE REVERBERATION CHAMBER The nominal room dimensions are 18.3 meters long by 10.3 meters wide with a height of 6.7 meters. The chamber volume is 1,286 cubic meters. These dimensions are important, as few reverberation facilities are large enough to test typically huge mining equipment. The floor is poured concrete with a sealer to make it acoustically reflective. The walls are built of hollow concrete block, 16 inches long x 8 inches high by 12inches thick. Each block has two hollow cores. The hollow block cores were completely filled with concrete with horizontal and vertical steel reinforcing bars 16 inches on center. This was done to supply a

By E. P. Youngman

Titanium ranks as one of the more abundant elements, is widely distributed, and occurs in concentrated form in numerous deposits. This substance was discoveres 140 years ago; but despite the efforts of metallurgists and chemists to find a place for it in industry, only within the last 10 or 15 years has the increased use of titanium pigments provided any extensive outlet for titanium ores. Even to-day titanium is confined to a few highly specialized industrial applications. The metal itself is now quoted regularly in trade journale, but scarcely yet can it be said that the production or use of the metal. has progressed very far beyond the laboratory stage. Ferroalloys containing the element were largely used for a time, especially in connection with the manufacture of Bessemer steel rails; but as American rail- ways adopted open-hearth rails in preference to Bessemer rails, the demand for the alloys in the rail manufacture gradually dwindled into insignificance. New outlets for ferrotitanium have been found in the steel industry; and the production of titanium alloys, both in the United States and in Europe, has increased in recent years. By far the largest use of titanium at the present time, however, is in pigments. The manufacture of titanium white began in Norway, but at present the United States is the leading producer. One of the two companies now operating in the United States is also the leading factor in European production. Although titanium occurs, in many minerals, the principal commercial sources are rutile (the natural oxide, Ti02) and ilmenite (iron-titanium oxide, FeO. TiO2). The latter is a coal-black mineral, but it is the one used in the manufacture of the titanium white of commerce, as well as in the manufacture of ferroalloys and arc-lamp electrodes. Rutile, the natural oxide, is not pure white and, being less common in nature, costs more; it is, therefore, reserved for use in the manufacture of titanium chemicals employed in relatively small amounts in dye works and bleacheries and for sundry minor purposes. This paper summarizes the titanium industry, with special reference to its economic aspects. It is offered as a survey of current trade literature and as a digest of material in the files of the bureau and is presented in response to numerous inquiries from prospective producers as to ways and means of exploiting deposits. (At present, much of the ilmenite consumed in this country comes from overseas, principally from British India..). A forthcoming circular, devoted to deposits of titanium-bearing ores, deals with foreign and domestic sources of supply.

Oct 1, 1930

By K. T. Menzies

This report documents laboratory and in-mine analyses of diesel exhaust pollutants carried out to assess the fate of potentially reactive species in the mine environment. Specifically, the concentration of stable compounds including carbon monoxide and carbon dioxide, and potentially reactive compounds including nitric oxide, nitrogen dioxide, sulfur dioxide, aldehydes, formaldehyde, acrolein, formic acid, odorants, particulates, soluble sulfates, and polynuclear aromatic hydrocarbons were determined. The concentration and mass emission rates of these compounds were measured in the laboratory under three engine speed and load conditions and with three exhaust control conditions, i.e., none, catalyst, water conditioner. Once calibrated, the engine was installed in the Bureau of Mines Safety Research Coal Mine and the concentration of exhaust pollutants measured at several distances downstream (inby) of the engine. Laboratory results confirm the relatively small effect of exhaust control devices on most pollutants under engine conditions of low speed and load. At higher engine speed and load, the catalyst is more effective in controlling many pollutants. The in-mine data indicates that during residence times, which are typical for miner/exhaust contact, most diesel exhaust pollutants do not decrease in concentration. The obvious exceptions are nitrogen dioxide, sulfur dioxide and formaldehyde. The concentration of these pollutants is reduced by up to 75 percent in five minutes. The lack of increase in levels of obvious reaction products indicates that surface loss may be a major sink for these pollutants.

Jan 1, 1980

By Oliver C. Ralston

[The NOJ'l..metals Division deals wi tt mi:leral n t inte .ded to be used a ra\o,f materials for extraction of metals. ~ _ ereas, a. materinl containing a chromite, if used' for production of c~1r()rrti1..1r.'l ::tetE' .. l or fcrrochromiu"1, 1,oJould be a chromi te ore, if used as 8. rcfrn.cto~J or for prod .1.ction of chromium chemicals, it is a chromi te-beari [. ~?oCl... Li;{eHise, a r:1a&neti te used for production of iron is a metallifero"'..ls ~in8re..i; if used 8.S a water-filtration granule in .:l magne.tically cleaned filter bed, it 'ould be a nonmetallic in-dustrial mineral.]

Jan 1, 1940