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By Richard L. Unger

The Crewstation Analysis Programs (CAP) is a package of computer programs that can be used to analyze some human engineering aspects of crewstation design (such as visibility and illumination) that have particular significance in underground mining. It was developed under the U. S. Bureau of Mines (USBM) Health, Safety and Mining Technology program at the Pittsburgh Research Center, Pittsburgh, PA. This manual describes the steps necessary to collect data in the laboratory to develop luminaire profiles for the CAP illumination analysis. It also describes how the CAP Illumination Model calculates illumination. 1.1 How CAP Calculates Illumination 1.1.1 Background -CAP currently includes assessments of visibility and illumination in the surrounding work area. The advantage of using computers for these types of analyses is that many design iterations can be tested quickly and efficiently to learn the effects of changes. This reduces the need for expensive testing using physical mockups. Another advantage is that design ideas can be tested in situations where it would not normally be possible. For instance, the effects of modifications to a lighting system or canopy design on visibility could be tested while the machine remains in service.

Jan 1, 1994

By Manuel Gomez

Carbon number distributions were obtained for tar acid fractions from five low-temperature tars by low-ionizing voltage mass spectrometry. Quantitative data for phenols representing seven structural compound types were examined by statistical analysis. It was shown that for the phenols discussed, the data could be represented by regression equations expressing phenolic concentration as a function of the reciprocal of the carbon number and the carbon-to-hydrogen ratio of the parent coal. The total concentration of each structural type present was found to depend on the molecular weight and boiling point of the initial member of the group. Carbon distribution data for the tar acid fractions studied support the view that low-temperature tars contain the same chemical compounds but in different proportions.

Jan 1, 1965

By A. B. Cecala

A new prototype bag nozzle system has been designed under a Bureau of Mines contract to reduce dust generated during the bagging operation on fluidized air baggers. A field analysis of the new system has shown that the bag operator's dust exposure was reduced 83 pet. The amount of blowback was reduced 89 pet, which corresponds to a significant product savings. The new prototype system has been operating for a substantial period of time with no major problems.

Jan 1, 1984

By G. S. Scott

In the course of the investigation into the causes, behavior, and control of mine fires, which the Bureau of Mines is now conducting, some attention was given to the subject of spontaneous heating. It is self-evident that the temperature of a pile of broken coal will rice if the rate of generation of heat exceeds the rate of brat dissipation and will fall if the opposite is the case. Factors that affect the rate of generation of heat are:

Jan 1, 1941

This paper has peen translated from the Russian by the United States Bureau of Mines and is issued as one of a series of circulars dealing with mining methods and costs in connection with a general study of this subject sponsored by the bureau. The paper presents some interesting features in connection with the methods employed in Russia and describes certain variations in standard methods which might conceivably be applied to a limited extent in this country.

Jan 1, 1930

By D. Harrington

A uniform hoisting-signal code for mines hoisting from more than one level, if adopted by all mining States, would be beneficial to employees and owners alike and should largely reduce the number of hoisting accidents. Misunderstood hoisting signals cause many shaft accidents involving injuries to men, damage to equipment, and loss of production from the resultant delay. Many of the metal-mining States have adopted codes for hoisting that are effective within the borders of that State but usually entirely different from the signal code, if any, in use in an adjoining State. For many years safety engineers have recognized this lack of uniformity as a distinct hazard, but a uniform code has never been adopted by the States or by the mining industry in those States that have not incorporated signal codes in their mining laws or mining regulations.

Jan 1, 1944

By Earle S. Burnett

This report outlines the experimental procedures for using a Burnett apparatus to obtain compressibility coefficients for multiphase, multicomponent fluid mixtures. The conventional Burnett method is described briefly whereby multiphase compressibility data can be obtained by first determining the compressibility factor, Z, as an isothermal function of pressure alone. Then starting at conditions of temperature and pressure where Z is known, the fluid is cooled at constant volume to some lower temperature at which the resulting pressure is measured, and a corresponding value of Z is obtained from a fundamental relationship between compressibility factors, pressures, and temperatures at constant volume. The isochoric treatment of the fluid, extended to still lower temperatures and along other isochors, eventually results in compressibility determinations for the whole two-phase system thus covered experimentally.

Jan 1, 1963

By D. H. Zellers

Since its inception the United States Bureau of Mines has fostered the development of portable mine lamps. Although there is still much to be desired with respect to illumination in coal and metal mines and the replacement of open lights has been slow the Bureau has been given credit for assisting materially in the development and introduction of the safe and efficient portable mine-lighting equipment available today. Much of the work conducted by the electrical section of the Bureau entails approval tests of various types of electrical equipment, including lamps; to be used in atmospheres that may contain methane or coal dust in explosive proportion. If a can lamp meets the requirements-for safety, efficiency, and adequacy, as published in Schedule 6B,4 it is approved and is generally known as a "permissible" lamp. The terms "approved" and '"permissible' often are used interchangeably. The manufacturer must put an approval plate on each approved lamp, showing it has mot the schedule requirements. The approval plate is not a guarantee that the lamp is safe. However, if the lamp, once in service, has not had any parts changed or improperly assembled or if carts that wear out or depreciate have been properly replaced it should still, be safe, efficient, and adequate for the service intended. Virtually all electric cap lamps in service today in the United States and a great many that have been sent to foreign countries bear the approval plate of the United States Bureau of Mines. Although many explosions have been attributed to open lights none has been charged against the permissible cap lamp. Nystagmus, a disease of the eye attributed to working under insufficient illumination, is practically unknown among; American miners, although it is quite prevalent among European miners.

Jan 1, 1935

By Raymond B. Ladoo

The uses of talc are many but are not, in general well known or fully developed within the last decade several companies have realized the possibilities of greatly increased use and have intelligently proceeded to develop some of the fields which seemed most promising. This has had a tendency to lift talc from the obscurity in which it had existed for years, but the work is only started and much remains to be done. Considerably more attention has been paid to the technology and utilization of talc in Germany and Austria than in this country, despite the fact that the United States produces 65 of the world's talc and Germany and Austria combined but 5.4%. In the "Bericht,uber die tatigkeit des verbends der talcum-interessenten in Oesterreich-Ungarn" (Proceedings of the Austro-Hungarian Talc Association), for the years 1912 and 1913, many notes upon new uses appeared, together with suggestions as to further development of old uses. Aside from a few notes on the use of tar in paper, little has been published in the English language upon this subject. By recent action of the Talc and Soapstone Producers Association (U.S.A.) funds for research into the properties and uses of talc have been made Available and it is hoped that markets will be materially broadened a a result of this work.

May 1, 1920

By A. W. Frolli

This paper, describing the mining and reduction methods and costs at the Oceanic quicksilver mine, is one of a series of similar reports being prepared by the Bureau of Mines on various mines in the United states. The property, which is owned and operated by the Anglo American Mining Corporation, Ltd., is 5 miles east of Cambria, San Luis Obispo County, Calif. It lies in a region of steep hills and sharply incised canyons on the west slope of the Santa Lucia Range at an elevation of about 500 feet above sea level. The climate is ideal for living and operating conditions. A 40-mile paved highway connects the mine with San Luis Obispo, the nearest convenient railroad town.

Jan 1, 1937

By Todd M. Ruff

This report summarizes ongoing research at the National Institute for Occupational Safety and Health, Spokane Research Laboratory, in which collision warning systems for surface mining dump trucks are being evaluated. Common accidents involve these large trucks running over smaller vehicles or pedestrian workers. Collision warning systems currently use one of several methods, including radar, radio-frequency-signal detection, or ultrasonic signals, to detect and warn of the presence of an object or person in the blind spots of the mining equipment. Most available systems have not been tested on large off-highway dump trucks. This report evaluates several systems on two sizes of trucks, a 50-ton-capacity truck commonly used in quarries and construction and a 240-ton-capacity truck commonly used in open-pit mines. Tests were conducted to determine false alarm rates, alarm effectiveness, and reliable detection zones for a person and a pickup truck. The results indicate that radar and radio-frequency identification systems show promise for this application and that several of the improved systems are ready for extensive field tests. However, challenges still exist in applying these technologies to large trucks.

Jan 11, 2000

By R. G. Dressler

The Federal Bureau of Mines designed, constructed, and operated a demonstration plant at Louisiana, Mo., to produce gasoline, liquid fuels, and organic compounds from coal by a modified Fischer-Tropsch gas-synthesis process. Satisfactory equipment was developed to produce and purify synthesis gas and convert it into the desired products. Coal or coke was gasified with oxygen and steam to make a gas consisting essentially of carbon monoxide, hydrogen, and carbon dioxide. Dust in the raw gas was removed by cyclone separation, water scrubbing, and electrostatic precipitation. Carbon dioxide, hydrogen sulfide, and organic sulfur were removed with diethanolamine, iron oxide, and activated carbon. The gas was passed over iron catalyst and was converted into synthetic liquids, which were then separated and fractionated into gasoline, diesel oil, other liquid fuels, and oxygenated organic compounds. A 39-day continuous run demonstrated the feasibility of the process. Addition of 3 milliliters of tetraethylead per gallon of upgraded (or finished) gasoline gave a product with an octane rating up to 90 by the research method. After a caustic wash, the diesel oil was of a superior quality; its cetane number was 60 or above.

Jan 1, 1961

By J. H. East

"INTRODUCTION .Very little information regarding coal mining in Spain has been published in the American technical press, and few people realize the extent of this industry or the conditions under which coal is mined. The information in this publication was collected in 1945 and consists of personal observations in Spain, statistics, and other data of a, general nature obtained from official sources.Spain produces bituminous coal, lignite and anthracite, but the total tonnage mined is less than the national requirements. Before the war, an appreciable tonnages coal was imported from Great Britain under the Anglo-Spanish treaty, which rebated import duties and effectually prevented competition from any other foreign source. The war stopped the major part of the important of British coal and caused rapid expansion of the domestic sources, but this was not sufficient to supply the industrial demand. Coal that formerly was not acceptable to industry because of quality is now mined and marketed. The Government, allocates the better-grade bituininous coal to the various industries in accordance with the national importance of the work in which they are engaged; for example, the railroads are allotted 100 percent of their requirements, but cement companies can obtain only 25 percent.The Government offered to inducements to increase the production of coal of any class, but the larger part of the increased tonnage obtained was in inferior grades; as a result, the lignite production was taxed, while a bonus was paid for bituminous-coal production in excess of the 1942 tonnage.The anthracite and bituminous-coal areas were severely damaged during the Civil War and many experienced miners migrated to the lignite mines in eastern Spain. This has resulted in an acute shortage, particularly the Province of Oviedo where the most important bituminous-coal deposits are located."

Jan 1, 1947

By Larry P. Jackson

As part of the current research effort in shale-oil chemistry conducted by the Federal Bureau of Mines, reduced chlorophyllins were prepared and pyrolyzed in an effort to identify the role of plant pigments and their decomposition products in the nitrogenous compounds found in the product of oil-shale pyrolysis. The properties of the chlorophyllin pyrolysates were related to the composition of the reduced chlorophyllins with particular emphasis on the amount and types of nitrogen compounds formed. A comparison based on the types of nitrogen compounds present was made betvJeen shale oil and the chlorophyll in pyrolsates. In order to make this comparison, a sample of shale-oil light distillate was separated into polar and nonpolar fractions, and a careful examination of the polar fraction was conducted to obtain an accurate picture of the types of nitrogen compounds present. The information gathered from these studies was used to evaluate reduced chlorophyllin as a model of oil-shale kerogen insofar as the production of nitrogen compounds was concerned. The results indicate that the reduced chlorophyllin does yield nitrogen products which are directly related to the nitrogenous compounds in shale oil, and it therefore represents a good model of shale-oil kerogen.

Jan 1, 1975

By D. Harrington

Although the explosion-fatality record for the fiscal year 1944 showed considerable improvement over those of the preceding 4 years, it is still fur from creditable, and the coal-mining industry and agencies interested in the prevention of coal-mine accidents should not be satisfied until accidents from explosions and fires are eliminated. In view of present knowledge of the methods of preventing explosions and fires, such disasters are inexcusable and discredit the mining industry. Despite this knowledge, far too many coal¬mine operators and employees continue to follow procedures that have resulted in disasters in the past. Included in the appendix to this circular are a number of safety measures designed to prevent coal-mine explosions and fires and metal-mine fires. Their adoption is essential if explosions and fires are to be prevented, as certainly they should be. An epidemic of disastrous mine fires of electrical origin during the past 2 years emphasizes the need for better methods of protection of underground electrical circuits. At present, committees of mining-electrical engineers, electrical-equipment manufacturers' representatives, and others are cooperating with the Bureau of Mines seeking means to solve this problem.

Jan 1, 1945

By W. H. Young

The thickness of the coal seam is one of the more important items influencing the productivity and general overall efficiency of operation of a coal mine. The average thickness of coal seams mined in the United States has changed very little in the past 40 years. The first measurement of thickness of bituminous coal and lignite seams was made for 1920, when the average thickness was 5.3 feet.2 The average thickness for later years was as follows: 1945, 5.4 feet; 1950, 5.3 feet; 1955, 5.2 feet; 1960, 5.3 feet; and 1965, 5.2 feet.3 Table 1 includes data on number and production of bituminous coal and lignite mines classified by 1-foot intervals of seam thickness mined in 1920, 1945, 1950, 1955, 1960, and 1965. Though bituminous coal and lignite are mined today from seams of exceedingly variable thickness--less than 2 feet to more than 50 feet--a large majority of the production, 62 percent in 1965, came from seams 3 to 6 feet thick. This is not surprising since the coal seam of moderate thickness presents the least mining difficulties.

Jan 1, 1967

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

APPENDIX F GOVERNMENT OFFICES CONTACTED DURING SURVEY 1. MESA Inspection Offices North Central District Duluth, Minnesota South Central District Dallas, Texas Rolla Subdistrict Rolla, Missouri Rocky Mountain District Lakewood, Colorado Salt Lake City Subdistrict Salt Lake City, Utah Spokane Field Office Spokane, Washington Osburn Field Office Osburn, Idaho Phoenix Subdistrict Phoenix, Arizona 2. MESA Research and Management Denver Technical Center Denver, Colorado Pittsburgh Technical Center Pittsburgh, Pennsylvania Metal and Non-Metal Office Washington, D C 3. State Offices (State plan States) Arizona State Mine Inspector Phoenix, Arizona New Mexico State Mine Inspector Albuquerque, New Mexico

Jan 1, 1976

By William E. Wallace, S. J. Page, B. L. Razzaboni, C. A. Hill, Pamela Mike, P. Bolsaitis, M. J. Keane, Val Vallyathan

"Respirable quartz cytotoxicity, as measured by erythrocyte hemolysis and pulmonary macrophage release of lactate dehydrogenase in vitro, is neutralized by boiling in water in glass test tubes for 10 to 40 minutes. The cytotoxicity is reduced to near zero by boiling l to IO mg quartz per milliliter water. For greater concentrations of quartz in water the hemolytic potential after 40 minutes of boiling approaches that of native quartz. Replacing the medium with fresh water midway through boiling results in full detoxification through 20 mg quartz per milliliter water. Pre-boiling the medium with silica reduces the detoxification effect. Detoxification persists after mild drying at l 10°C for 8 hours, and persists after three days of resuspension in water at room temperature.INTRODCJCTIONResearch underway to determine interactions of quartz and other mineral dust surfaces with pulmonary fluids and alveolar macrophages in culture led to the observation that when dusts were autoclaved in aqueous suspension, their cytotoxic effects on macrophages were suppressed, in some cases fully and even after several days incubation with the cells. This finding was in direct contradiction to earlier results from both short term macrophage lysosmal enzyme release assays, as well as longer term cytotoxicity assays from macrophages in culture; in those studies, dusts were steam autoclaved at 121°C with no liquid water but with steam present. 1.2 However detoxification under boiling conditions has been reported in other research. 3 It was decided to use the hemolysis assay to further investigate these findings, because of its sensitivity simplicity and cost.RESCULTS AND DISCCISSIONRespirable quartz dust used in this study was taken from a stock of crystalline silica, Min-U-Sil; obtained from Pennsylvania Sand Glass Corporation, fractionated in air with a particle classifier. The small size fraction retained for use was 80% less than S micrometer particle diameter, with an area equivalent median diameter of 1.24 micrometers as estimated by automated image analysis. The silica was at least 98.S mass percent silica as determined by X-ray energy spectrometric analysis; and the crystalline form was alpha-quartz as determined by X-ray diffraction. It's specific surface area was 3.97 square meters per gram as determined by nitrogen adsorption isotherm methods. I"

Jan 1, 1990

By R. Hogg, E. Kaya

"The presence of agglomerated particles in airborne dust in coal mines has been confirmed by SEM examination of static samples collected on substrates. In addition, the effect of agglomerated particles on the performance of cascade impactors and cyclone-type personal samplers has been studied. Simple procedures have been developed for evaluating the extent of agglomeration in air-borne dust by comparing the observed size-selectivity of the sampling devices with that expected under idealized conditions. Applications of these techniques in the laboratory and in underground mines are discussed.INTRODUCTIONAirborne dust is invariably present in mine atmospheres. Particle size is a primary factor in determining the behavior of the dust, its effects on miners' health and the effectiveness of dust control measures. Obviously, agglomeration of the dust particles can have important effects on: ""natural"" dust removal processes such as settling• the use of water sprays etc., for dust control• pulmonary deposition characteristicsIn addition, the presence of agglomerates could influence the effective toxicity of the dust. For example, ultrafine particles are often thought to be relatively unimportant in the development of respiratory ailments because of their low deposition efficiency. However, the latter could be substantially increased if such particles were present in larger agglomerates. It is by no means obvious that there should be significant agglomeration of the airborne dust in a mine atmosphere. In fact, calculations based on the classical coagulation theories indicate that, at the kinds of dust concentrations that exist even in what would be regarded as “very dusty"" atmospheres, the coagulation half-time* .should be of the order of weeks or even months. On this basis, agglomeration would be expected to be essentially negligible. On the other hand, laboratory experiments (Polat et al., 1991) have revealed very extensive agglomeration in the airborne dust released during the crushing of individual coal and mineral particles. It is postulated that such agglomeration occurs immediately at the point of dust generation. In other words, many of the fine fragments produced on fracture are never completely separated from their neighbors."

Mar 1, 1992

By C. W. Huggins

The primary objective of this Bureau of Mines research was to measure the size distribution of respirable quartz collected at metal mines, nonmetal mines, and processing plants to select the best reference standard for use in quantifying quartz in mine and plant dust samples. The secondary objective was to size all the nonquartz particles collected at the same sites. Particle size measurements were made on 29 samples using a scanning electron microscope in the backscatter mode of operation, interfaced with an image analysis system. The Mine Safety and Health Administration, Denver, CO, provided the 29 samples, which were collected at mines and processing plants in 19 states. The accumulated particle size measurements indicate that NBS 1878, minus 5-f.lm Hin-U-Sil, and minus 5-f.lm Supersil would be preferred over Silver Bond B as reference standards for most quantitative determinations by X-ray diffraction and infrared spectrometry. The respirable dust samples collected at sand plants, however, would be better served by a new reference standard having a quartz particle size distribution of approximately 2.2 um, as none of the four existing reference standards matched closely with them. Commercially available NBS 1878 and minus 5-um Hin-U-Sil CQuid be used as reference standards for 28 of the 29 samples studied in this investigation.

Jan 1, 1986