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By M. D. Marshall

A survey showed that there were 24 bin-related fatalities in the 5 year period of 1975 to 1979 in the minerals industry. Only 4 victims wore safety belts and only 1 of these had a second person attending his lifeline, as mandated by Federal safety regulations. Not one victim observed the three main Federal safety regulations governing work in and around bins. A study was conducted on the force necessary to pull victims partially buried in sand and limestone. Recommendations are made on procedures and safety equipment that can minimize bin-related accidents. A Handbook, directed to the plant engineer responsible for bin design and safety, was also issued detailing bin designs and flow-aid accessories as a function of the flowability of the stored material to better maintain material flow from bins. A comprehensive table of the flowability of many materials produced in the minerals industry is presented and simple procedures given for determining the flowability of materials if not available.

Jan 1, 1984

By E. D. Wilson

A study of factors related to subsidence was specified in a project proposal entitled "Structural Analysis of Block-Caving Operation, San Manuel Copper Mine, Pinal County, Ariz.," approved by the Bureau of Mines early in 1953. This proposal was designed by Charles H. Johnson, then chief of the Base Metals Branch of the Minerals Division, Washington, D. C., assisted by Dr. Leonard Obert, chief of the Applied Physics Branch, Region VIII (now Region V), College Park, Md., and E. D. Gardner, chief mining engineer, Bureau of Mines, Washington, D. C. It read as follows: This project is a study of the mechanics of undercut block caving in a deep ore deposit. The San Manuel is a low-grade disseminated copper deposit containing nearly a half billion tons of ore lying at depths of 500 to 2,000 feet. Development is just starting. Production is to begin in 3 to 4 years (in 1956) at a rate of 30,000 tons of ore a day, or 60,000 tons of copper a year. A Government loan of $90,000,000 /subsequently increased to $94,000,000/ and a long-term Government purchase contract support the capital investment, which will total about $110,000,000.

Jan 1, 1957

By S. F. Mauser

This report describes the study of factors which affect medium voltage (661 - 1000 volts) trailing cable splices used in underground coal mines. Improvements in quality, dependability, and design of splice kits and shop splices are presented in the study results and recommended guidelines and regulations. Recommended research programs are included which describe approaches for development of the recommended guidelines and regulations for medium voltage trailing cable splices. The basis for the conclusions and recommendations presented in this report is included in three appendices which describe a survey, splice examination, and general requirements development prepared during the progress of this study.

Jan 1, 1977

To improve the level of hearing protection by providing workers with an inexpensive, easy-to-use device to check earplug fit. Background Approximately 30 million workers are exposed to hazardous noise on the job, placing them at risk of permanent hearing loss, tinnitus, and other disorders. Although the preferred solution is to eliminate noise through engineering controls or to reduce noise exposure through administrative controls, hearing protectors are critical when noise is unavoidable. Studies of hearing protector users have shown that average protection values in the real world are much lower than the labeled noise reduction ratings determined in laboratories with trained and motivated subjects. Even worse, many hearing pro­tector users get virtually no protection at all because of poor fit. The studies also show that users have a harder time achieving adequate protection levels with earplugs than with earmuffs. It?s difficult for users to tell if earplugs are working well just by looking at them. A more accurate approach is to check how much they block or ?attenuate? noise. Earplugs vary in their attenuation characteristics, with most providing a maximum of 20?35 decibels of noise reduction when worn correctly. Any earplug that?s suitable for use in noisy settings will attenuate noise by at least 15 decibels. Personal fit testing is an effective way to help hearing protector users improve the fit and protection levels of the devices. However, existing fit-testing systems are expensive and unsuitable for use at many industrial worksites.

Dec 1, 2008

[Module 10. Internally Cued Operating Contingencies Prerequisite: Modules 1-7 - Estimated Instructional Time: 2.42 hrs. Module Abstract Trainees, using programmed instruction, describe the cues, consequences, operational sequences, and possible causes resulting from loss of air pressure from power fluctuations, and from a failure of the automatic lubrication system. Although some of the contingencies may be initially signaled by an alarm or from the oiler, each trainee will demonstrate proficiency in the appropriate operating techniques and procedures. This module also includes a review component for those trainees identified in the assessment exam as requiring less detailed instruction.]

Jan 1, 1976

By F. S. Kendorski

This report covers the work on developing criteria for determining when a hazard exists when mining stratified mineral deposits beneath bodies of surface water. The nature of water bodies is considered, the disturbance to the strata induced by mining is described, inundation case histories reviewed, reasonable water inflows derived, and methods of mining to prevent or minimize the hazard are presented. Criteria are given whereby effected industries and agencies can recognize a potential hazard and plan a mine accordingly, releasing considerable mineral reserves otherwise considered unminable.

Jan 1, 1979

By W. P. Yant, H. C. Fowler

"INTRODUCTIONHydrogen sulphide is probably the most toxic gas associated with crude oil. Hydrocarbon (petroleum) vapors themselves are harmful to the human system, but hydrogen sulphide, when present, is usually more important from the standpoint of health and safety. These conclusions were reached in an investigation of the toxic gases encountered in the transportation end refining of high-sulphur petroleum. The results of that investigation are presented in Bureau of Mines Bulletin 23l. although the writers of Bulletin 231 paid no direct attention to the production of oil in the field, they attributed to hydrogen sulphide reports of accidents caused by gas in the oil fields of Mexico.During the development of oil fields in Texas, a ""poison gas"" was encountered that constituted a decided health and safety hazard. The present report discusses an investigation of this gas made in July, 1926.The major portion of the investigation was conducted in the Panhandle field of Texas, but the study also includes the Big Lake and McCamey fields.Scope of WorkThe work undertaken in each field included:Examination of the gas-coming from representative wells at various locations in the field; also analyses of the gas-air mixtures to which the workmen were or might be exposed.Observation of symptoms of poisoning and severity of these symptoms."

Oct 1, 1926

By A. W. Effinger

The Bureau of Mines used regression analysis and applied statistical methods in an effort to rationalize the results of an experiment examining the effects of certain variables on carbon deposition in a reservoir for thermal recovery of petroleum. Although none of the 15 trials of the original experiment resulted in the response of weight-percent of carbon regarded by the experimenter as adequate, values calculated using canonical analysis in two trials yielded responses 33 and 54 percent higher than the minimum acceptable figure. The actual responses differed by less than 3 and 6 percent, respectively, from the predicted responses. Methods are described for defining a path of increasing response based on the minimum point and the response surfaces and for defining a set of values for the parameters in question, which result in increased response, A detailed explanation of the mathematical process used in this analysis is presented in the appendix for ease in computer programing the technique.

Jan 1, 1970

By R. L. Marek

The number of Persons fatally injured in the petroleum industry in California in 1930 was 50, a decrease of 20.6 per cent from 1929, when 63 men accidentally lost their lives. The decrease in the number of fatalities for 1930 has caused the first downward trend in the fatality curve of the California petroleum industry since 1927 and is coincident with a period of little active development in new fields, the shutting in of many wells, and reduced activity in the older fields of the State. That a direct relationship exists between the number of accidental deaths and the rapidity of new field development is particularly emphasized by the fact that in 1929, a year of intensive field development in California, 48 men were killed in the drilling and producing division, whereas in 1930, a year of less development work, only 25 men were killed in this division. The figures for the average number of drilling and producing wells in 1930 decreased appreciably from comparable figures for 1929 and a greater percentage of producing wells were shut-in in 1930 than in 1929.

Jan 1, 1931

By R. L. Marek

The number of persons fatally injured in the petroleum industry in California in 1930 was 50, a decrease of 20.6 per cent from 1929, when 63 men accidentally lost their lives. The decrease in the number of fatalities for 1930 has caused the first downward trend in the fatality curve of the California petroleum industry since 1927 and is coincident with a period of little active development in new fields, the shutting in of many wells, and reduced activity in the older fields of the State. That a direct relationship exists between the number of accidental deaths and the rapidity of new field development is particularly emphasized by the fact that in 1929, a year of intensive field development in California, 48 men were killed in the drilling and producing division, whereas in 1930, a year of less development work, only 25 men were killed in this division. The figures for the average number of drilling and producing wells in 1930 decreased appreciably from, comparable figures for 1929 and a greater percentage of producing wells were shut-in in 1930 than in 1929.

Jan 1, 1931

By J. D. Davis

THIS REPORT gives results of an investi¬gation of the carbonizing properties of coals from Pittsburgh bed, Jamison No. 9 mine, Marion County, W. Va., and from Upper Freeport bed, Bull Run No. 1 mine, Preston County, W. Va. The study included Bureau of Mines-American Gas Association tests at 800° and 900° C. and various chemical and physical tests designed to evaluate the plastic, expanding, and agglutinating properties of coal. A blend of each coal was carbonized in the 500-pound slot oven. The carbonization sample of Pittsburgh coal contained 2.7 percent moisture, 35.8 percent volatile matter, 54.4 percent fixed carbon, 7.1 percent ash, and 0.9 percent sulfur. It contained 60.9 percent fixed carbon on the dry, mineral-matter-free basis and had a heating value of 14,780 B. t. u. per pound on the moist, mineral-matter-free basis. It therefore ranks as high-volatile A bituminous and was blended with low-volatile Pocahontas No. 3 coal. Upper Freeport coal contained 2.8 percent moisture, 27.7 percent volatile matter, 60.9 percent fixed carbon, 8.6 percent ash, and 1.0 percent sulfur, as carbonized. It contained 69.5 percent fixed carbon on the dry, mineral-matter-free basis and therefore ranks as medium-volatile bituminous. It was blended with high-volatile A Pittsburgh coal from Allegheny County Pa.

Jan 1, 1952

By J. W. Paul

This report is one of a series of papers on coal mining methods and costs which are being prepared through the sponsorship of the U. S. Bureau of Mines for the purpose of bringing to the industry a knowledge of methods as they are used at the present time, and data on certain features which govern costs, safety, and conservation. The methods employed are, influenced by local conditions with respect to the character and dip of the coal, the nature of the, roof and the thickness of the overburden, and the means employed for roof support and its control.

Jan 1, 1929

By E. J. Gleim

An important phase in the Bureau of Mines investigation of electrical machines designed for operation in gassy coal mines is testing enclosures of electrical components for explosion-proof qualities. In brief, this testing consists of filling and surrounding the enclosure with an explosive atmosphere of methane and air and then igniting the atmosphere within the enclosure to determine (1) Whether the resulting explosion is confined without discharge of flame; (2) whether the enclosure walls are permanently distorted; and (3) whether excessive pressures are developed within the enclosure. Ordinarily, the pressures encountered in routine testing do not exceed 100 pounds per square inch gage. Hence, the designer of the machine does not have too much difficulty in taking corrective measures to prevent flame discharge and distortion of the enclosure. Occasionally, however, the explosion pressures greatly exceed 100 pounds. Then the goblet of the designer may not be solved so readily, From experience over the year 0, the testing personnel often can predict that certain construction will result in high. Pressures, but, only in a very general way, has it been possible to advise designers what modifications might be made to reduce the explosion pressures to normal values. For example, if high pressures were developed in a motor starter having a partition with an opening through it, some enlargement of the opening may appear to be the logical procedure, but it has not been- possible to give information concerning the exact amount the opening should be enlarged to prevent development of high pressures .

Jan 1, 1952

By Donald P. Schlick

Respirable dust provisions of the Federal Coal Mine Health and Safety Act of 1969 are designed to protect the most important resource of the coal mining industry--its workers. The Act imposes two respirable dust standards of 3.0 milligrams per cubic meter of air after June 30, 1970; and 2.0 milligrams per cubic meter of air after December 30, 1972. Under Federal regulations, each operator is required to carry out a dust sampling program established by the Secretary of the Interior and the Secretary of Health, Education, and Welfare, This program features the sampling of "high risk" face workers to establish that the exposure of each miner is below the dust standard, Mining sect ions, continuously in compliance with the regulations, may sample at less frequent intervals. In addition to requiring the mining company to take respirable dust samples, the Bureau of Mines will perform in-depth dust inspections twice a year, as well as frequent "spot inspections." The Bureau has established a semiautomatic computerized operation capable of processing over 1 million samples per year. This facility will be linked to various Bureau offices by a telecommunications system to provide automatic data printouts within hours after samples have been weighed.

Jan 1, 1970

By I. L. Nichols, K. C. Dean, P. H. Johnson

Hydrochloric acid , sulfuric acid , and chloridizing roast- water leaching methods for dissolution of cesium and rubidium from Maine , Canada , and Southern Rhodesia pollucite ores and their flotation products were investigated by small- scale tests . Optimum conditions were determined to be ( 1 ) for hydrochloric acid leaching , use 12.7 equivalents of 8.8 normal acid per equivalent of cesium in the sample and leach for 6 hours at 100 ° C ; ( 2 ) for sulfuric acid leaching , use 12.7 equivalents of 14.4 normal acid and leach for 2 hours at 120° C ; and (3 ) for chloridizing roast - water leaching , roast minus 200 - mesh ore, limestone , and calcium chloride in a ratio of 2 : 4 : 1 , respectively , for 1 hour at 900 ° C , and leach the calcine for 1 hour at 80 ° C with enough water to give 35 pct solids . Extractions of cesium from ores and flotation products containing over 20 pct cesium were in excess of 97 , 93 , and 96 pct for the hydrochloric acid , sulfuric acid , and chloridizing roast - water leach processes , respectively .

Jan 1, 1964

By H. P. Hermance

Preliminary examinations of the Parker and Webb deposits were made by E. E. Maillott, Bureau of Mines engineer in July 1942. The chemical and spectrographic analyses included in this report wore made at the Eastern Experiment Station of the Bureau of Mines at College Park, Md., under the general supervision successively of S. M. Shelton and of Paul M. Tyler, formerly regional engineer, Eastern Region. Beneficiation tests were conducted under the supervision of Frank D. Lamb. The mineral exploration was under the general supervision of J. D. Bardill, formerly district engineer. Acknowledgment is gratefully made to the St. Joseph Lead Co., in particular to John S. Brown and P. J. Mechin for their assistance. Special acknowledgment is made to the American Metal Co., Ltd., ,Ind to T. C. Moore for furnishing core-drill and assay data; to the Universal Exploration Co. and P. B. Jennings; and to the Northern New York Mining Corp. and C. H. Sprague for their permission to publish the core-drill dta. Excellent cooperation was given by Dr. W; M. Agar and C, L. Rogers of the Geological Survey.

Jan 1, 1949

By H. Kenworthy

Sulfide-ore concentrates containing cobalt, nickel, copper, lead, and iron from the operations of the National Lead Co. at. Fredericktown, Mo., were treated successfully on a laboratory scale to recover more than 90 percent of the cobalt, nickel, and copper. A cobalt -nickel-bearing, lead-copper matte., produced by the St. Joseph Lead Co. at Herculaneum, Mo., was treated to produce a lead-zinc fume, a copper sulfide concentrate, and a cobalt nickel-iron product, netting a recovery of over 75 percent of the cobalt and about 90 percent of the nickel and copper. National Lead Co. bulk concentrates were chlorinated with gaseous chlorine to form anhydrous metal chlorides and sulfur chlorides, sulfur chlorides were recovered by distillation, a high percentage of the ferric chloride was converted to ferric oxide, and the chlorinated residual metals were extracted with water. Metal ions were removed from leach liquors by pH-controlled fractional precipitation as hydroxides. Cobalt solutions "were prepared from cobaltic hydroxide, and procedures were developed to remove contaminating metal ions. Purified cobalt solutions were employed as electrolytes for deposition of high-purity cobalt.

Jan 1, 1953

By W. N. Marchant

The Bureau of Mines performed chemical research to elaborate details of sulfur chemistry pertaining to the citrate flue gas desulfurization process in which sulfur dioxide (SO2), absorbed (as bisulfite ion) in a buffered sodium citrate solution, is reduced by hydrogen sulfide (H2S) according to the overall reaction 2H2S + HSO3 + H+ ? 3S + 3H20. The rate-limiting step in the process was shown to be the reduction by H2S of thiosulfate (S2031-) that is formed as an intermediate. Pseudo first-order kinetic measurements were made at room temperature to retard the reaction sufficiently that adequate analysis was possible. These measurements showed the rates of the following net processes to be -d [S02]/dt (pH 4.5) = (0.409±0.050)min-1 [S02]; d [S2032-]/dt (pH 4.5) = (0.199±0.017)min-1 [S02]; -d [S2032-]/dt (pH 4.0) = (0.0437±0.0265)min-1 [S2032-]~1; -dH2S/dt (pH 3.9) = (21.6±3.0) mmoles/min-atm [H2S]g1.4, where [H2S]g is the partial pressure of H2S in the gas phase, in atmospheres, and the rate describes the consumption of H2S, in millimoles per minute; d[S]/dt (pH 4.0) = (38.0±3.4)min-1 [H2S]1, where [H2S] is the concentration of H2S in solution. Hydrogen ion consumption during the slow phase of regeneration was shown to occur at (2.1±0.5) times he rate of thiosulfate consumption, which is interpreted as evidence for the following as the rate-limiting reaction: 2H2S + S2032- + 2H+ ? 4S + 3H20 A scheme consisting of five sequential general reactions is proposed to account for sulfur formation.

Jan 1, 1981

By E. P. Youngman

This paper presents one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative, to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the mining laws of British Guiana has been prepared from the best available sources in Washington and is, released subject to amplification and correction, if necessary, by United States foreign-service officials. INTRODUCTION The sources of information available in the preparation of this paper are the following: 1. The Crown lands ordinance, No. 32 of 1903, September 26, 1903.

Jan 1, 1934

By Richard A. Watson

A frequency-shift keying (FSK) modulator-demodulator (modem) network has been devised for the Bureau of Mines mine-monitoring systems. This network permits an unlimited number of remote stations to communicate with one central station over the same pair of wires. The network operates at a speed of 4,800 Bd at distances up to 5 miles. This report describes the development and operation of the modems. The theory of operation, schematic diagrams, and printed circuit board layouts are provided. Although the modems were built for a specific application, a more general use is discussed whereby the network would operate with a typical serial channel format.

Jan 1, 1985