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By M. D. Schlesinger

Mercury exists in coal at very low levels; the structure of coal, the vapor pressure of mercury, and its almost universal occurrence introduce unusual problems into the analytical methods. Round-robin analyses by several laboratories, each using its own techniques, indicate that the average mercury content of coal is about 0.2 part per million. Some western coals are as low as 0.05 ppm.

Jan 1, 1971

By L. H. Wullstein

Bureau of Mines research on methods for reclaiming land disturbed by the minerals sector of the economy has produced a specific procedure for effectively germinating seed of Indian ricegrass, a drought-tolerant plant valuable for reclaiming arid and semiarid sites. This report describes the procedure which consists of acid-treating the seed followed by temperature and light cycling treatments. Use of the procedure resulted in an average germination rate of 29 percent, ranging from 18 to 56 percent. Seed subjected to long cold treatment but with acid treatment yielded an average germination rate of 9.2 percent, ranging from 6.6 to 14.7 percent. Untreated seeds (controls) gave germination rates less than 0.1 percent.

Jan 1, 1979

By George McCaa, H. C. Howarth

"During recovery operations following a recent coal-mine explosion, 12 small fires were encountered near the break line of pillar extraction in a large panel. All of the fires except one were quickly extinguished by the rescue and recovery parties. This fire had found its way into a large quantity of loose material at a corner of the cut-through between two rooms, about 100 to 150 feet from the break line of an extensive goaf; had it been necessary to seal the fire, the inclusion of this break line not only would have made the work difficult but would have made the section hazardous as it probably would have given off gas. The fire covered a floor space of about 100 square feet and when discovered was burning briskly, with the flame extending to the roof at a height of 3 or 4 feet; it was the cause of much apprehension on the part of those in charge of the recovery operations and resulted in delaying the work considerablyThe object of this article is to describe in detail the method by which the fire was brought under control and finally extinguished, so that other persons encountering similar conditions may have the benefit of the experience.When the fire was discovered a request for rock-dust, fire extinguishers, and other fire fighting equipment was telephoned to headquarters on the surface. The promptness with which fire fighting equipment and material was provided was a big factor in finally extinguishing the fire and illustrates one of the many advantages of a good organization for fire-fighting. Material was transported in mine cars to a point on the main hauling road about 1,200 feet from the fire. It was then carried to the scene of activity by workmen. The first material to be delivered at the fire was a number of fire extinguishers of various types. The contents of 30 to 35 of these were discharged on the fire and with the aid of a small quantity of rock-dust were sufficient to smother the flame temporarily. It was the opinion of several persons who were present when the fire extinguishers were used that the acid-soda type of extinguisher gave more effective results than the two or three other types used.When the contents of all of the fire extinguishers had been exhausted the fire was temporarily smothered, but as there appeared to be danger that the flame would burst forth again, means for completely extinguishing the fire were"

Feb 1, 1929

By L. C. IlsLey

As part of its work for the improvement of safety conditions in mines , the Bureau of Mines has undertaken to establish a list of permissible storage - battery locomotives for use in gaseous mines , and , to this end , has issued Schedule 15 , "Procedure for Establishing a List of Permissible Storage -Battery Locomotives for Use in Gaseous Mines . " Up to the present time , two approvals * have been issued under this Schedule , and considerable testing work done on four other applications which have been made for approval . Prior to the publication of Schedule 15 , the Bureau conducted both field and laboratory investigations to determine the hazard from the batteries used in mine locomotives . ** These investigations indicated that the safety of the locomotive would depend largely on proper care of the battery , also on the use of a battery as mechanically rugged as possible . For this reason the Bureau staff , in testing locomotives submitted for approval , considered it advisable to subject the batteries to a jarring or bumping test to prove their adequacy as regards mechanical endurance and ruggedness . These tests on the batteries of the locomotives are described below.

May 1, 1922

By S. J. Pearce

"INTRODUCTION AND SUMMARYComplaints have been made regarding dust respirators that may be used in coal-mining operations. Some of these complaints may be due to improper use of the respirator, inadequate knowledge of its purpose and mode of functioning, poor choice, poor fitting, or inadequate maintenance. It is hoped that this circular will answer these complaints by discussing the various factors relating to the proper use of dust respirators in general and in coal mines in particular.It is pointed out that dust respirators are not to be used as a substitute for dust-control measures. The construction, functioning, choice, fitting, and maintenance of dust respirators are discussed.FIELD OF USEThe function of the dust respirator is to prevent the wearer from inhaling harmful quantities of dust by removing dust from the air he inhales.A dust respirator is not to be used as a permanent substitute for dust-control measures. It is to be used as a temporary substitute until dust-control measures can be instituted or as a protective means where dust-control measures are impracticable, as in applying rock dust in bituminous-coal mines.The following sections of the ""Federal Mine Safety Code for Bituminous-Coal and Lignite Mines in the United States"" 2/ emphasize the fact that every effort should be made to keep the amount of dust in the air of the working places as small as possible:"

Mar 1, 1950

By Homer J. Ballinger

A multiple drill carriage or "jumbo," which is believed to be unique in both design and performance, was constructed and has been in use for the past year at the Bureau of Mines experimental oil-shale mine near Rifle, Colo. This jumbo mounts four long feed percussion drills and is so designed that two men can operate all four drills. Before the jumbo was placed in operation, a minimum of eight man-shifts was required to drill 72 fifteen-foot holes in headings 60 feet wide and 27 feet high. The sane round is now drilled by two men in about 6 hours. Over 500 feet of drilling per man shift is easily and consistently accomplished. Use of the jumbo has resulted in a 75 percent reduction in drilling labor and a substantially lower drilling cost.

Jan 1, 1950

By Edward D. Thimons

A remote-actuated stench gas fire-warning system has been designed and tested by the Bureau of Mines. This system makes use of the hard-wire network for the mine's phone pager system, thus greatly reducing the system cost. By locating stench gas canisters with remote-actuation release capabilities near working sections, the fire-warning time can be greatly reduced. In a test of the system in a Missouri lead mine, the time required to warn miners of a fire at two working faces was reduced from about 20min with the conventional system to less than 4 min with the remote-actuated system.

Jan 1, 1984

By Richard L. Rains

The 15,770-acre Worm Creek Roadless Study Area is in southeastern Idaho about 8 miles (mi) west of the northern portion of Bear Lake. U.S. Bureau of Mines personnel examined the roadless, area during the summer of 1984. No mineral resources were identified within the study area. There were no mines or mining claims in the study area in 1984. However, the study area is blanketed with oil and gas leases, but no known productive horizons have been identified within nor nearby. The roadless area is in the Cordilleran fold-thrust belt and is underlain by Paleozoic and Mesozoic marine strata more than 50,000 feet thick. The trace of the Paris thrust fault is 2 to 3 mi east of the study area and has an eastward displacement of about 4 to 7 mi.

Jan 1, 1985

By D. J. Parker

State governments are increasing their efforts each year toward promoting the safety of miners .. Accidents underground are being avoided and mines made safer by means of revising and adding to their mining laws , by enforcing them through mine inspection departments , and by hearty co - operation with other agencies working miners ' safety . The U. S. Bureau of Mines is glad to testify to the co -operation that it receives from State mining departments in its safety work ; reports of the field mining engineers of the Bureau bear witness almost daily to the efforts of the States toward safety in mining . * This Through the courtesy of Mr. William Ogilvie , District State Wine Inspector of District No. 2 , with headquarters at "cAlester , Oklahoma, the Bureau has been furnished with a copy of a letter sent to various mining companies of Mr. Ogilvie's district in Oklahoma, relative to safety in Oklahoma mines . letter shows both the vigorous efforts which the State of Oklahoma is making toward increased safety in mines , and the recognized value of the types of electric cap lamps approved by the U. S. Bureau of Mines as " permissible " for use in gaseous mines ; it is accordingly reproduced in part : "hen during my first inspections of several coal mines in the district I found gas , or fire- darp being given off more or less constantly from the freshly cut coal at numerous points throughout the mines , I became uneasy relative to safety conditions , and am still considering your safety from many angles , but I am more concerned about the gas given off and the coal dust produced daily, than any other factor at the present time .

Jun 1, 1922

By BUREAU OF MINES

The cheapest method of handling gravel in placer mining operations is by hydraulic mining . In working gravel deposits by hydraulic mining , it is essential that an abundant supply of water under sufficient head can be economically developed and that there is sufficient grade for sluice boxes and for disposal of the tailing . Without dumping facilities , simple hydraulic mining is an impossibility . The cost of hydraulic mining may range from 2 cents a yard under favorable condıtions to 12 or even 20 cents under less favorable conditions and to 35 cents or more a yard in Alaska , according to conditions of operation , and if frozen gravel is encountered . When it is necessary to elevate gravel , the costs may exceed 60 cents a cubic yard . When the natural conditions do not permit of hydraulic pining proper , other methods of elevating the grade are employed , some of which are described below . Bucket dredging has replaced hydraulic mining in importance in California and other states where hydraulic mining was once extensively carried on , and is by far the cheapest method of elevating gravel when mechanical methods are required and the physical conditions are suitable for dredging . Dredging costs vary greatly under the different conditions encountered , and the total amount of gold to be recovered must of course be enough to warrant the cost of a dredge installation . Gold dredging operations in the United States are fully described in Bull . 127 , U.S. Bureau of Mines .

Jan 1, 1922

Introduction The NIOSH Office of Mining and Construction Safety and Health Research has redesigned its Mining Safety and Health Web topic page. The updated page incorporates a significant amount of new safety and health information, plus an improved layout to better serve stakeholder needs. It also provides back-ground information about the NIOSH Mining Research Program, including research awards, core competencies, unique labs, community and educational outreach, and a brief discussion of how the research program is structured. The new Web topic page can be found at www.cdc.gov/niosh/mining. "Search" Feature The redesigned Web topic page features improved search capabilities. The "Search Mining" feature on each page lets you search only the NIOSH Mining Safety and Health Web topic page. The user can still search the entire NIOSH Web page by using the "Search NIOSH" option. New Safety and Health Topics Developers expanded the "Safety and Health Topics" and reorganized the site to make it easier to find information. Each topic link now has a significant amount of new and updated information, as well as links to related topics of interest. Safety and health topics include dusts, diesel exhaust, hearing loss, contact with electric current, fires, explosives, ventilation, emergency management, new and older workers, and education and training. All topics can be accessed from the home page (Figure 1). Publications Although the Web topic page highlights many of the most requested publications on the safety and health topic links, you can find a complete list of downloadable publications as well. More than 600 mine safety and health publications are now downloadable from the page. Short summaries let the user quickly identify publications of interest. Products The updated Web topic page offers more than 120 NIOSH mine safety and health products, including training exercises, toolbox talks, videos, computer software, guides, and checklists, many of which are downloadable. If not, instructions are given on how to obtain copies. Some of our products include: • Software to analyze horizontal stress, design pillars for longwall mines, and select roof bolts for ground control. • Educational software including the Hearing Loss Simulator, which simulates the effects of noise and aging; and Coal Country, which teaches children about coal formation, mining techniques, and everyday uses of coal. • Utility software including the HazCom Helper software to assist individuals in writing a HazCOM plan, as required by the Mine Safety and Health Administration (MSHA), to track hazardous chemicals at their mine sites. • Guides for troubleshooting roof support systems, under-ground workstation design, and seating design. • Training exercises and videos that can be used for safety training. Data and Statistics General mining statistics are used by a wide variety of stakeholders. The NIOSH Mining Web topic page offers statistical graphs, tables, maps, fact sheets, and other publications that document the mining population, injuries, fatalities, diseases, and occupational exposures for all mining commodities. If users prefer to analyze data themselves, downloadable files of MSHA data are available. These cover employment, production, injuries, fatalities, and accident data from 1983 to the present and are available in both SPSS® and dBASE® formats.

Jan 11, 2005

"Reports are sometimes heard of one ill effects of pneumatic tools on the hands of workmen. In consequence of such reports, Dr. Francis M. Barnes, Jr., M..D. of St. Louis, Missouri, was retained by the operators to make an investigation of conditions in the Bedford, Indiana, region, and the result of this investigation was published the Journal of the Missouri State Medical Association, Volume 16, February 1919. A brief review of this report may be of interest to all users of pneumatic tools, or operators of plants where such tools are employed.The investigation was made during December 1917, and involved an examination of general working conditions, and a careful physical examination of stoneworkers who had long used pneumatic tools. As the Bedford district is the most important structural limestone producing center in the country, the results of this investigation may be regarded as fairly conclusive as to the general effect of pneumatic tools on limestone workers."

Jan 1, 1920

By Philip W. Holland

The U.S. Bureau of Mines has designed and built an inexpensive, weatherproof, temperature-controlled cabinet to provide temporary housing for analytical instrumentation. The cabinet consists of an inverted Styrofoam ice chest, an electric fan for air circulation, and a proportional temperature controller equipped with a thermistor sensor and a light bulb as the heater. The cabinet provides a constant-temperature environment for a moisture analyzer and a strip chart recorder when outside temperatures range from -SO to 21° c.

Jan 1, 1993

By Albert E. Long

By the USB of X-ray diffraction methods, scientists have learned how the atoms in a diamond crystal are arranged and how the atoms are tied together by chemical bonds. They have found that, even though the bonds between all atoms of the diamond have equal strength, they are so distributed that there are more bonds in certain layers or directions through the crystals than in others. The unequal distribution of the bonds in certain directions creates planes, within the diamond, of unequal strength and resistance to abrasion. The location and disposition of the directions that are relatively harder than the others were determined by Slawson and Kohn 3/ in 1950. By plotting these directions on stereographic projections they delineated the hard regions on the surface of the diamond, but only those trained in the methods of crystallography can readily interpret their diagrams. The principal purpose of this report is to present information that will help individuals without previous training in crystallography to learn to recognize the special features of the surfaces of diamond crystals that are definite guides to the location of the various hard directions of the stones. A crystallographer trained in using various precise laboratory instruments might consider such rudimentary criteria as rather unscientific, but these simple characteristics of diamond crystals are practical clues which anyone equipped with a magnifying lens can find and recognize. The use of the special faces, points, edges, and growth lines as a gui.de in orienting a diamond will allow it to be placed in a position reasonably close to the optimum. Preliminary results of experimental work conducted by the Bureau of Mines indicate that this is all that is necessary in setting diamond-bit crowns. This experimental work demonstrated that setting bits with the hard vectors of the diamond as cutting points greatly reduces the diamond loss and increases the efficiency of the bit.

Jan 1, 1952

By Franklin D. Cooper

The value of nonfuel mineral raw materials produced in the United States in 1978 was $20 billion. In 1979, total value increased to an estimated $24 billion, up 20% from 1978. Of the principal metallic ores produced in 1979, about half showed increased quantitative output and all showed increased value per ton compared with that of 1978. Most nonmetallic commodities showed increases in quantitative output and in average value per ton. Because of its decreasing share of the world market, the domestic mineral industry's concerns were the increasing costs of capital, labor, and energy; withdrawals of public lands from mining; and the increasing cost of environmental regulations that tended to deter or delay investment in the Nation's capacity for producing essential minerals.

Jan 1, 1980

By D. B. Dow

The transportation of any commodity which is actually or potentially a source of fire or explosion, has been made safe, insofar as humanly possible, by rigid requirements as to inspection mechanical safety devices, and by printed labels. For the most part these precautions have been sufficient. This is evident when it is considered that in the thousands of instances in which commodities with a great fire risk have been transported, few disasters have occurred. This paper deals with the recent gasoline explosion which occurred at Memphis, Tennessee. At 7:50 a.m. January 24, 1921, vapors from a tan: car of gasoline became ignited and resulted in a blast that killed eleven people and badly injured nineteen others. Probably forty or fifty men, women, and children received slight injuries from falling debris or from burns. The explosion wrecked an oil plant, leveled a block of frame buildings, and broke window panes within a radius of five blocks.

Feb 1, 1921

By Oliver C. Ralston, Foster Fraas

"INTRODUCTION The predominant characteristic of powdered mica is the thin -plate shape of the particulars, and the thinner the plates, the more enhanced is this characteristic. Consequently, it is frequently desirable to grade mica according to the thickness of the plates. Concerning the various possible methods for grading mica, very little has been published. There is also no information on the relative quantities of mica per given range of plate thickness. This paper presents a graphical method that shows how these quantities are distributed and how the different methods of grading compare.CUMULATIVE BULK DENSITYBulk density, which is an indirect measure of the plate thickness, was determined in a small cylindrical cup of 3.37 cubic centimeters volume. The mica was placed in the cup under a standard procedure. The densities thus measured checked these determined in a 273 cubic centi¬meter cup with less than a 2 percent error.In calculating cumulative densities it is important to know how they are averaged. In any grading operation the bulk density of a series of fractions is determined. Starting with the lowest density fraction, the cumulative percent under-density can be calculated through the various fractions. It is possible that quantity may be measured by volume or weight and that the averaging may be done by a number of methods. However, experimentally it has been shown that the quantity must be by volume and that the averaging must be arithmetic. This is illustrated in table 1, in which the calculated and actual bulk densities are listed."

Sep 1, 1942

By W. E. Miller, G. S. Scott, G. W. Jones

"INTRODUCTION One of the major activities of the Bureau of Mines is the promotion of safety in mining and the mineral industries. Research is undertaken in connection with these problems to determine the explosion and ignition hazards of combustible gases, liquids, and solids and to investigate means of reducing them.Occasionally the Bureau is asked to determine inflammability or ignition temperatures to enhance safety in nonrnineral industries. From time to time it has complied with such requests when no other agency was available to do the work and the investigation could be conducted with a minimum of time and expense. The present investigation is one of this class.Nicotine (C10H14N2), a colorless combustible liquid having a boiling point of 246°C, is usually obtained from tobacco and its products by extraction processes. When heated to its boiling point it decomposes; the purified product is obtained from tobacco extractions by distillation at reduced pressures or is distilled in a current of inert gas.It has an unpleasant odor, a burning taste, and in the undiluted state is highly toxic. Under certain conditions it can be oxidised to nicotinic acid and in the near future may therefore become of considerable economic importance. Nicotinic acid is a component of the vitamin B complex now commonly used to fortify white flour and other foods that normally are deficient in these vitamins."

May 1, 1942

By D. W. Frommer

Laboratory mineral-dressing investigations were conducted on talc-bearing samples from Arkansas and Texas under the Bureau of Mines program of examinations and surveys, which is concerned, in part, with the improvement of conservation and utilization of domestic mineral resources. Two of the soapstones in question were successfully upgraded by flotation, utilizing stage additions of a frother and an amine to promote their talc content. The process could enable the producers to meet more rigid specifications of higher priced talc commodities. INTRODUCTION Talc is an industrial mineral with distinctive properties, such as softness, smoothness, large surface area in relation to mass, chemical inertness, and good retention as a filler, that make it particularly valuable to a number of industries. Sales to 6 industries -ceramics, paint, insecticide, rubber, roofing, and paper -consumed 84 percent of the domestic production of talc, pyrophyllite, and ground soapstone in 1952. Mine production in that year totaled 600,908 tons. Sales of crude and ground material were 593,147 tons valued at $11,347,317.2/

Jan 1, 1956

By l.J Prosser

from 1990 to 1996, 16 states reported 92 injuries from falls of roof, rib or face in the more than 90 underground stone mines in the United States (Fig. 1). Missouri, Pennsylvania and Kentucky accounted for 48% of the total number of injuries (Fig.2). Of this total, 11 miners were killed. Of the 11 fatalities, 10, or 91 %, were associated with unrecognized loose or failed rock within the roof beam. Additionally, unrecognized roof beam failures resulted in a majority of the falls of ground injuries occurring in underground US stone mines from 1990 to 1996.