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By Launa Mallett, Charles Vaught, Michael Brnich, ROBERT PETERS

Interviews of 48 miners who escaped underground coal mine fires revealed that none of them had ever, before that incident, worn their self-contained self-rescuer (SCSR) either in training or in a real emergency. Consequently, they were ill-prepared to use this emergency breathing apparatus. One persistent problem stemmed from the fact that miners had no notion of breathing resistance, nor of the fact that it would get more difficult to breathe the longer they wore their device. As a result, many of those who were interviewed had simply removed their mouthpieces and breathed ambient air. This is obviously behavior that should be trained out of the workforce. Unfortunately, because of high costs and difficult logistics, miner training is unlikely to ever include donning and wearing an apparatus on a regular basis. In order to give workers a better idea of what to expect from their devices, therefore, the National Institute for Occupational Safety and Health researchers developed a tabletop (paper and pencil) simulation based upon actual predicaments evacuees had reported encountering. The simulation is designed to emphasize important points related to donning and wearing a self-contained self-rescuer in a mine fire escape, and, by doing so, to bring miners' expectations more in line with what their actual experiences would be. The simulation was field tested in six training classes at three different mining operations. In all, 99 individuals were involved in completing the exercise and rating its properties. In their ratings 88% of the respondents indicated they thought the scenario could definitely happen in real life, and over 80% agreed they had learned something new. From the field test data it was concluded that the simulation had authenticity and potential value as a teaching tool. The simulation was therefore used in a pre-test/post-test control group experiment to determine whether it led to improvements in miners' scores on a true-false test of their SCSR's functional capabilities and proper usage. Eighty-three miners were included in this part of the study. As expected, miners who had participated in the training exercise scored significantly higher on their post-test than miners who had not.

By James P. Bennett

The U.S. Bureau of Mines investigated the role of imported natural flake graphites in dolomite-carbon refractories used in steelmaking processes and evaluated carbon fibers as a potential substitute. Varying quantities (1.5-30 pct) of natural flake graphite and carbon fibers were added to test samples. The effect of the additions on modulus of rupture (75°-2,750° F), deformation under load (2,750° F), and air-slag-metal resistance (3,000° F) was studied. Carbon purity of natural flake graphite additions did not influence hot strength, deformation under load, or air-slag-metal resistance. When the quantity of 90-pct-carbon graphite addition varied between o and 30 wt pct, hot strength was highest, deformation under load lowest, and air-slag-metal wear the least at 10 wt pct. As test temperature increased from 500° to 2,750° F, the hot strength difference became less. Carbon fiber additions were limited to 1.5 pct in dolomite-carbon brick. At this level, physical properties were generally comparable to those obtained with natural flake graphite, but were below values obtained with 10-pet-f1ake graphite additions. Carbon fibers are not considered a satisfactory substitute for natural flake graphite.

Jan 1, 1989

Southeast Alaska's mining industry has come to life after nearly 50 years of relative dormancy. Commencement of operations of the Greens Creek Mine in 1989 marked a turning point in the industry as the first large scale mining operation in the region since closure of the Alaska-Juneau Mine in 1944. The Greens Creek Mine is now the nation's largest silver producer. Other large scale mining projects are now on the drawing board, including development of the Kensington Mine and reopening the Alaska-Juneau Mine, which could become North America's largest underground gold mine. The region's mining industry includes more than these large scale projects, however. For example, a significant level of mineral exploration occurs each summer in Southeast Alaska. In addition, mining operations in British Columbia and Yukon Territory are generating jobs and income in Southeast Alaska.

Jan 1, 1992

By F. W. Richard

This paper describing the mining practices at the Ground Hog Unit of the Asarco Mining Co., a subsidiary of the American Smelting and Refining Co., is one of a series being prepared by the United States Bureau of Mines on mining methods, practices, and costs in the various mining districts of the United Stated. The Ground Hog mine is at Vanadium in the Central mining district, Grant County, N. Mex., about 1.0 miles east of Silver City and 2 ½ miles southwest of Santa Rita. A branch line of the Atchison, Topeka & Santa Fe Railway connects Vanadium with Deming, about 45 miles southeast.

Jan 1, 1930

By Richard V. Ageton

Compressed- air blowers are frequently used both in large and small metal ines , not only as an aid to ventilation , but in some mines as a substitute for an dequate ventilation system . As a temporary fixture , blowers have their uses , but hey should never be used in lieu of a permanent ventilation system. A number Probably the most common error made in placing dependence on compressed- air lowers as an aid to underground ventilation is the tendency to over- rate their cooling efficiency . It is a very common but natural error to assume that compressed air which issues freely from a blower is of the same temperature as the compressed air which issues freely from the exhaust port of a rock-drilling machine . of readings were taken in different mines of the temperature of the rock- drill exhaust , of the compressed air flowing from the blowers , and of the surrounding air In both cases . In general , the temperature of the rock- drill exhaust was from 10 to 30 degrees below that of the surrounding air , in many instances being slightly below freezing , 32° F . The average temperature for a number of compressed-air lowers and for the mine air surrounding them is shown in Table I.

Jan 1, 1922

By F. F. Netzeband

This report relates to the sulfur industry of seven States--Arkansas, Kansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas--and is part of a national study of the sulfur industry by the Bureau of Mines. Markets as used in this report are divided into two components for individual analysis-- (1) supplier markets which include regional Frasch and byproduct sulfur producers and (2) consumer markets which include processors and manufacturers requiring sulfur in their operations The term sulfur as used in this report includes brimstone, native sulfur, elemental sulfur, or sulfur equivalents.

Jan 1, 1964

By David J. Kusler

This report describes a primary or direct, continuously sampling, and automatically averaging gravimetric method for analyzing gaseous mixtures of carbon dioxide, carbon monoxide) hydrogen, and (by volume measurement) nitrogen. The gaseous mixture is analyzed by passing it at a controlled and definite rate through a system that permits carbon dioxide and water retained by appropriate absorbents to be determined and the residual-gas volume (essentially nitrogen) to be measured. The accuracy and dependability have been established by comparison with very carefully conducted Orsat analyses. The method was developed for, and has been satisfactorily applied to, the analysis of blast-furnace top gas. It permits relatively attention free operation, using simple and low-cost materials usually found as basic equipment in the analytical laboratory. It provides, over a wide range of time or sampling intervals (from less than 1 to over 24 hours), the average composition, in terms of volume-percent, for those components usually determined in blast-furnace gas, if (as is usual) the flow rate of gas from the blast furnace is essentially constant over a selected analysis interval. Oxygen and methane are not determined; but, since these gases are normally absent or present only in traces, their analysis is seldom required.

Jan 1, 1959

By P. M. Ambrose, C. Travis Anderson, Cresap Moss, R. S. Dean

"MANGANESE METALMethods of PreparationMethods of preparing the manganese metal that has been used in chemical and metallurgical investigations have passed through a cycle. Most of the investigations made before the turn of the century used Moissan's pyrophoric manganese. 5/ This material was made by electrolysis into a mercury cathode and distillation in vacuo. It was essentially a pure material, and investigations in which it was employed (with proper precautions against oxida¬tion) led to accurate results concerning the intrinsic behavior of metallic manganese.An early investigation of the properties of ""Manganese-by-Mercury"" was made by M. Guntz. 6/ He prepared manganese by electrolysis of a concentrated MnCl2 solution with a mercury cathode. The manganese amalgam was pressed through chamois and distilled in vacuo (2 to 3 cm. of mercury) at 200°0., slowly rising to 250°0. Guntz recognized especially the decreased reactivity of manganese with increased temperature of mercury distillation. The most careful and com¬prehensive study of manganese made by this method is that of Kuh 7/ whose work unfortunately was never published in an accessible journal.Royce and Kahlenberg 8/ studied the electrode potential of manganese made by this method."

Nov 1, 1939

By Henry M. Harris

Low-carbon shales from 65 deposits and 11 sources of coal-mine waste in western Oregon and Washington were tested in a rotary kiln for their suitability as raw material for expanded aggregate. Shales from 41 sources bloated enough to produce crushed, expanded aggregates, weighing less than 65 pounds per cubic foot in the preliminary tests. The samples were judged on the basis of processing qualities, physical properties, and size and uniformity of the source. Nine low-carbon shale deposits and three coal-mine waste sources were selected for more extensive bloating tests and for examination of the expanded aggregates in concrete shapes. Composite samples from these 12 sources and from 2 commercial operations, when processed for testing in concrete shapes, had bulk densities ranging from 37.S to 72.9 pounds per cubic foot. Damp-cured concrete shapes made with these aggregates had bulk densities ranging from S6 to 119 pounds per cubic foot, and all but three of the lightweight concretes had crushing strengths ranging from 3,270 to 6,810 p.s.i. Properties of the lightweight concretes were compared with those of concrete shapes made with commercial aggregates, and with sand and gravel.

Jan 1, 1962

Effective control of respirable dust is one of the most serious problems associated with longwall mining in the United States. This report describes the development and laboratory testing of dust collectors for use on double drum shearers. Systems tested included: ? High Capacity Flooded Bed Scrubber ? Water Powered Extraction Cowls ? Water Powered Extraction Drums ? Water Powered spot Scrubbers. The systems were tested using tracer gas in a full-scale model of a longwall shearer face. This report provides a detailed description of the test facility, test methods, and system test results.

Jan 1, 1982

This report describes the activities and publications of the Bureau of Mines Health and Safety Research and Testing Center, Pittsburgh, Pa., for the fiscal years 1960-65. It includes a discussion or work being conducted on roof control, dust explosions, ventilation, health, coal mine fire control, and electrical-mechanical testing, and an abstract of each paper published during the report period.

Jan 1, 1966

By Scott Turner

We are here today to witness the graduation of 63 young men as Engineers in the mineral industries . It is an important occasion and one in which the public takes a keen interest , since this school has long been famous for the educational facilities it affords young men, and for the high professional standing of its graduates . : : : It is fitting that once each year we should pause to review the path the student has traveled , and to reflect upon the perspective opening before him as an engineer . I was invited to come from Washington to take part in this ceremony and to say something to these young graduates . In searching for a theme ," it occurred to me. that perhaps my best contribution would be to duscuss certain beliefs as to college training , deal with the situation in which the young engineer finds himself on graduation , touch on the new ideas of the social and political responsibilities of the engineer , and point out what he may expect to find in practice , and , above all , what he must do to orient himself properly in the mining profession and maintain the best traditions of our brotherhood . Let us first review your college days and see what they have done for you . I am told there are still many temptations in college . I know there used to be . Rest assured the same holds true in the professional life ahead of you. The main difference is , perhaps , that your greatest temptations in college were those offered by your teachers , who tried to entice you into realms of harder work, closer application , increased concentration , clearer thinking and better understanding , by animating your curiosity and increasing your powers of reasoning and of observation . In other words , here you have carefully and systematically been decoyed toward finer and loftier things . Do not expect that similar helpful influences will greet you on every side in your professional life . Often quite the contrary is the case .

Oct 1, 1930

By J. F. Messerly

The purity of three specially prepared samples of benzene was determined with an adiabatic, low-temperature calorimeter with automatic control of shield temperature. Extensive measurements were made on each sample to determine how variations in operating procedures affect melting-point and freezing-point as well as purity data obtained by the calorimetric method. Detailed results of the investigations are presented, and effects of different operating procedures are discussed, together with problems encountered in interpretating experimental results.

Jan 1, 1963

By R. M. Gooding

This paper presents a short history of the production of mineral-energy fuels and energy from waterpower in the United States, with brief discussions of the utilization of each of the fuels and hydropower, and a look at fuels competition and interchangeability. Basic data, in figures and tables, are brought together in this publication for the production of coal in the United States from 1800 to 1960, for crude petroleum, natural gas liquids, and natural gas from 1859 to 1960, and for hydropower since 1900. Production for each segment of the fuels complex in the principal producing States from 1946 to 1960 is shown. Data are not included for consumption as such or for imports and exports.

Jan 1, 1963

By Joseph H. White

In its investigations looking to the improvement of health condi- tions and the increase of efficiency in the mining industry, the Bureau of Mines, in cooperation with the Bureau of Public Health, is studying sanitary conditions in and about mines with the intent of pointing out how those conditions that are a menace to the health of the miner may be most efficiently removed or remedied. An out- line of sanitary betterment work at mining villages in the Birming- ham district of Alabama has already been published by the bureau," and in this bulletin are presented suggestions on the planning of mining towns and the construction of miners' houses. The bulletin does not pretend to be a treatise on the so-called "housing problem," and mentions sociologic issues only incidentally. It is assumed that the influence of proper shelter on health is understood and that not a lack of appreciation so much as a lack of knowledge of the best remedies is responsible for many of the undesirable conditions that exist at mining towns. The purpose of this bulletin is to supply facts on the building of well-lighted, well- ventilated, warm, attractive, and economical houses for miners, these houses being assumed to be units of an industrial village or town the building and management of which are under the control of a corporation, so that special conditions hold which do not apply to houses built and owned by individual miners. From this it is not to be inferred that the company-controlled town is the best system or the only one in vogue. The discussion of this side of the subject in all its phases is too involved to be included in this paper. One element in favor of the company-controlled town is its possible immediate responsiveness. Hence this assumption. Also the assumption is made that a-new isolated town is being built, and hence the selection of the site, the arrangement of the streets, and the situation of the houses are discussed before the house itself is treated, for one of the most important factors in obtaining an economical sanitary house is a well-selected town site. Many of the suggestions, however, may be applied in improving conditions in existing towns, in building new houses in old towns, or in repairing old houses. Emphasis must be laid on the fact that as a rule a mining village has a shorter life than a manufacturing town. Economy is emphasized frequently because the discussion is predi- cated upon the assumption that the miner himself is to pay for all that he gets. House rent will doubtless be expected to bring in a reasonable return on all money invested in streets, sidewalks, water supply, sewer system, and houses; in other words, the town is to be run on a business and not on a paternal or charitable basis. "Fair and reasonable" precludes, of course, the idea of excessive returns. Some companies do not consider it good policy to realize as high a rate of interest as an independent realty company would be war- ranted in realizing. Under some circumstances part of the town improvements might be charged as "expense of the industry," that is, to the consumer. The isolation of a mining town introduces a unique responsibility. As the miners are practically obliged to rent the company houses, the officials of the company ought to scrutinize all expenditures in- volved so that house rent may be reduced to a minimum. In a way the town builders are placed in the position of trustees. They deter- mine, within certain limits, what proportion of a man's wages shall be spent on house rent. This consideration should restrain fanciful and unnecessarily expensive building; the other extreme should like- wise be avoided. True economy should be distinguished from cheap- ness. Ugly, insanitary, uncomfortable shacks should not be built even if, because of their cheapness, there is a demand for them from tenants. The obligation of the industry to society as a whole as well us to the tenant ought to forbid this. A cheerful, strong, healthy, virile race will not rise out of the filth and squalor of cheap hovels. An insanitary environment often does its damage slowly and silently; vitiated air does not, like mine gas, announce its deadly work by an explosion. As Talbot⚫ says: Health depends in part on freedom from infection. The probability of obtain- ing that freedom will be greatly increased by maintaining the body at a high state of vigor, or "vitality," as it is popularly called. This implies the promo- tion of all agencies which have to do with the physical well-being as well as with the control of sources of infection. Many men realize that in building houses for their workmen they are invested with a peculiar responsibility that must be wielded wisely, and in large developments they call into consultation the land- scape architect, the sanitary engineer, and the building architect, as well as the mining engineer.

Jan 1, 1914

By H. A. Dierks, H. B. Link

The purpose of this investigation was to develop a practical feeder apparatus to introduce comparatively large pieces of coal and similar material into a pipeline under pressure in connection with the vertical hydraulic transportation of solids , termed " hydraulic hoisting . " This method of hoisting the precrushed run - of - mine product of an underground mine has been given unusually wide attention abroad and could be of considerable significance to the U.S. mining industry in its search for operating improvements and cost reduction . A lock-hopper assembly was developed after a series of sinking velocity tests were made by dropping anthracite in a column of water . The system functioned reliably as an automatically operated feeder apparatus .

Jan 1, 1964

By F. M. Goodwin, John Campbell, G. W. Jones

"INTRODUCTION The investigation of the general hazards of combustible gases and vapors in manholes owned by the Edison Electric Illuminating Co. and the study of methods for eliminating these hazards, conducted by the Bureau of Mines, the Edison Electric Illuminating Co. of Boston, and the Boston Consolidated Gas Co. since 1929, was continued during 1933.From May and through December 1933 these tests were supplemented by a study of the manholes of the New England Telephone & Telegraph Co. The test crew was under the direct supervision of John Campbell, superintendent of the Special Service Department of the Edison Electric Illuminating Co., and F. M. Goodwin, vice president of the Boston Consol¬idated Gas Co.The procedure of sampling manhole atmospheres and of shipping the samples to Pittsburgh was the same as that used heretofore. In previous reports the relative explosibility of the samples was calculated by adding the percentages of the illuminants, hydrogen, carbon monoxide, methane, and ethane, dividing the total by 6.5, and multiplying by 100. Experience has shown that the factor 6.0 is more nearly correct; therefore, this has been used in calculating the relative explosibility of all the samples listed in appendix A and B of this report. If gasoline vapor is present a smaller factor must be used.ACKNOWLEDGMENTSThe cooperative investigation was arranged through the interest and effort of W. C. Bayliss, president of the Edison Electric Illuminating Co. of Boston; W. C. Beckjord, vice president and general manager of the Boston Consolidated Gas Co., and A. C. Fieldner, chief engineer, Experiment Stations Division, United States Bureau of Mines. Thomas H. Haines, superintendent, Distribution Department of the Edison Electric Illuminating Co., cooperated heartily in furnishing both men and information for the work."

Oct 1, 1934

By Parry. V. F., John B. Goodman

"INTRODUCTION The Denver region coal field, covering an area of approximately 7,640 square miles, extends from the Wyoming State line to the middle of El Paso County, Colo. The coal in this region is subbituminous in rank. Much of it is used as domestic fuel. During the last decade the production of coal in this field has remained fairly constant at an average of 2,600,000 tons per year. This production has come from 50 to 60 mines, 88 to 90 percent of the production being from the section of the field north of Denver.According to the Standard Specifications for Classification of Coal by Bank of the American Society for Testing Materials 4/ the coals in this region are classified in the Subbituminous B and C group. On the as—mined basis, they contain about 22 percent moisture and average 9,600 B.t.u. per pound. They are noncoking and slack to a variable extent when exposed to the weather. This is characteristic of subbituminous coals."

Aug 1, 1939

By Earl T. Hayes

[This work represent a continuation of the efforts of the Metallurgical Division of the Bureau of Mines to ascertain and apply knowledge of miner physics to processes metallurgy.]

Jan 1, 1941

By Joan Weinberg

The economy continued to expand during the third quarter, as real GNP rose at a seasonally adjusted annual rate of 3.8%, up from 2.5% in the second quarter (table 1). Continued job gains (see below), higher incomes, and an increase in installment debt, resulted in a nearly 20% increase in consumer spending on durable goods. Consumer expenditure on nondurables fell slightly, while spending on services continued at a moderate pace. Nonresidential fixed investment climbed nearly 24%, as producers purchased more durable equipment. Residential fixed investment was adversely affected by rising interest rates, which slowed new home construction from January to August, 1987 to a rate 11.2% below a comparable period in 1986. Net exports of goods and services deteriorated slightly, after three consecutive quarters of improvement. The volume of net exports has risen 15% for the year, contributing to economic and employment growth, but large price increases on imports have slowed the improvement in the nominal trade balance. Although U.S. goods have declined in price relative to foreign goods because of the devaluation of the dollar, faster growth in exports is hampered by austerity programs in developing countries, and emphasis in Germany and Japan on curtailing inflation and fiscal deficits.

Jan 1, 1987