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By Chris Nelson

Two pieces of European Union (EU) legislation together establish requirements for protection against risks from vibration at work. The vibration directive1 specifies duties of employers to protect workers from risks from exposure to vibration; the machinery directive2, specifies duties of manufacturers and suppliers regarding the safety of machinery marketed in the EU. This paper discusses both directives and the standardisation programmes that support them. It also addresses the implementation of these requirements in Great Britain. Employers’ duties: the vibration directive This directive requires employers to assess and control risks to health and safety arising from hand-arm vibration (HAV) and whole-body vibration (WBV). Member States were required to implement the directive in national legislation by 6 July 2005. Employers are required to eliminate vibration risk at source, or reduced to a minimum. The duties include: assessing risk and exposure; planning and implementing the necessary risk control measures; providing and maintaining suitable work equipment; providing workers with information and training on risks and their control; and monitoring and reviewing the effectiveness of the risk control programme. Daily exposure exceeding a specified action value triggers a requirement for a programme of technical and organisational measures to minimise vibration exposures and the resulting risk, and the provision of health surveillance. Exposures above a specified limit value are prohibited. When conducting their risk assessments, employers are required to “assess and, if necessary, measure” the vibration exposure of workers, for comparison with the action and limit values. Vibration measurement in the workplace is not expected in all cases and the use of vibration information from equipment manufacturers is specifically mentioned. This provides a link with the machinery directive (see below). Manufacturers’ and suppliers’ duties: The machinery directive The machinery directive, first introduced in 1989, is intended to remove barriers to trade. It puts duties on manufacturers and suppliers who place machinery on the European market to design their products to eliminate or reduce risks to health and safety and to warn the user of any residual risks, providing information required for safe use (for example, operator training, maintenance and selection of consumables). There are specific requirements for minimising risk from vibration in the design and construction of the machine and, in the case of hand-held, hand-

Jan 6, 2006

By Michael Horn

[An economic trading region made up of 22 eastern Washington, northern Idaho, and western Montana counties, with Spokane, Washington as the central place, was defined for this study. modeling system with the, 1985 county database was to create an Input/Output based model of the regional economy. The leading ice, with respect to income, employment, value of exports, and total industry output are shown for each county and the region. The value of total industry output from natural resource based industries is also shown for each county and the region. Interindustry transactions, final demand, and value added components for the region are shown in the Regional Gross Flows Table. The total gross output for the region is valued at $36.7 billion. Total industry output for the region is $18.1 billion. The region provides $5.4 billion in income to a work force of 286,000. Spokane County, Washington accounts for about 50 percent of the regional total industry output, income, and employment. Both Spokane County and then as a whole produce about 80 percent of the total industry output for final demand with remaining 20 percent going to intermediate inputs for further production. Spokane County exports about 43 percent of its total output while 35 of the regional output is exported. Exports account for more 50 percent of the total in 18 of the 22 counties within the region. About 9 percent of the total industry output from Spokane County and 19 of the total output from resource f: .t *III For counties Spokane a industry ? N from nafural resource based represents 18 percent ?.{1 to 71 s. ?-{ and averages 39 r. ?-11 of total county +' ' 7:. FS.-f.?) If t. Natural resource it us -t for more than 50 coutny 1 s ? sass in seven counties within region.]

Jan 1, 1992

By J. Roth

The purpose of the present study is to increase the safety of explosive storage. This was accomplished by: a) review of the histories of recent and past magazine explosions to define causes and trends; b) observation of present-day explosive storage conditions and practices at active mines; c) examination of existing Federal regulations on explosive storage to determine whether they address all conceivable safety problems, whether they contain redundant or obsolete standards, and whether their intent is clearly stated; d) recommendation, for safety improvements and for revision and clarification (if necessity) of governmental regulations. Magazine explosions are rare. A recent increase in magazine explosion frequency must be attributed to a large increase in deliberate (criminal or malicious mischief) explosions. Fires of various origins account for the remaining explosions of the past decade. During 1884-1926 several lightning-generated explosions occurred in non-metal magazines, but none recently. It appears that the contents of a well-constructed, metal magazine are immune to direct lightning strikes, regardless of whether the magazine is grounded or not grounded. Grounding a metal magazine cannot be harmful, but it may well be superfluous. Magazines were observed at 34 widely separated mines and storage problems were discussed with personnel at these mines. In general, storage conditions and practices were found to be satisfactory. Usually, only small quantities of explosives are stored on mine property since most explosives are brought in by suppliers when needed. MSHA and BATF standards on explosive storage appear to cover safety aspects adequately. However, certain revisions are recommended to clarify some of these standards and to reduce inconsistencies in their enforcement.

Jan 1, 1983

By Robert Stefanko

A series of workshops were conducted -with invited participants from the coal mining industry to identify the most pressing research and development needs of the industry. Six workshops were held on the following subjects; Research Priorities for Mining-Oriented Universities, R&D Needs-for Surface Coal Mining, R&D Needs for Deep Coal Mining, R&D Needs for Anthracite Coal Mining, R&D Needs for Coal Mine Health and Safety, and R&D Needs far Environmental Control in Coal Mining.

Jan 1, 1975

By R. E. Peterson

Scrap iron is partially oxidized at elevated temperatures in the selective oxidation process to produce iron oxide and a dense residual metal of high purity. Investigation of the process was confined to converting automobile hulks into useful products. In one test series, compressed, sheared automobile scrap was processed at 1,000° C in a 36-foot-long rotary kiln at feed rates ranging from 300 to 1,200 lb/hr. Less fuel was required to maintain the temperature at the higher feed rates because of the heat generated from the burning of the combustibles and the oxidation of the iron. The bulk density of the residual metal exceeded 75 pounds per cubic foot. In an attempt to lower the quantity of contaminants in the residual metal, another test was designed using automobile hulks which had been prepared by ripping, a low-cost method of scrap fragmentation. Before oxidizing the ripped scrap approximately 62 percent of the total copper was removed in a tumbling, screening, magnetic separation and hand-sorting system. Cast iron made from the residual metal obtained by selective oxidation contained 0.15 percent copper; iron oxide scale obtained from the kiln averaged 0.13 percent copper. Pellets made from the scale demonstrated compressive strengths necessary for blast furnace reduction; lead and zinc were removed by volatilization when the induration was performed in a reducing atmosphere.

Jan 1, 1972

By E. J. (Kirk) Conway

The objectives of this project were to: (1) determine the extent to which maintainability design concepts and principles have been applied to the design of underground coal mining equipment, (2) try to assess its impact on productivity and personnel safety, and (3) develop maintainability guidelines to enhance the design of new or rebuilt equipment. An equipment design review was completed at ten operational coal mines. The purpose was to identify design approaches and features that enhanced and degraded the maintenance process. Mine management, safety, and maintenance personnel were also interviewed to identify machine specific design problems. Six original equipment manufacturers were visited and the procedures used to enhance the maintainability of Their equipment discussed. Volume I of the Final Technical Report presents an overview of procedures and protocol used and a summary of the findings. Volume II includes the maintainability design guide for mobile underground mining equipment.

Jan 1, 1988

By Paul J. Remington

The field data gathered as part of the measurements described in Volumes I and II were re-analyzed in the low frequency regime (.1 Hz to 1 Hz) where motion sickness normally occurs. These data were compared co the international standard ?ISO 2631 Addendum 2: Evaluation of exposure to whole body z-axis vertical vibration in the frequency range 0.1 to 1.0 Hz." For both underground mining machines and surface mining machines the results showed that one would not expect motion sickness to .be a severe problem. New field data were gathered on the vibration reduction performance of various seat designs found on surface coal mining machines. The vibration during normal operation was measured on the seat using the standard seat pad accelerometer package described in the previous two volumes and simultaneously on the floor of the machine at the base of the seat. Preliminary indications are that the so-called high performance seats used for operator vibration reduction do not offer significant improvement over conventional seats.

Jan 1, 1984

By Grant R. Brown

The report provides guidance for determining those environmental impacts associated with the surface mining of steeply pitching coal seams. In addition to the environmental impacts, four additional issues are addressed, namely (1) Time and motion studies of those coal mining systems employed in mining seams which pitch in excess of 250, (2) Assessment of those mining techniques, (3) Development of rationale for the mining methods employed, (4) Identification of the reclamation practices and determine whether these practices were in compliance with appropriate Federal and State regulations. Five surface mines located in three geologically distinct basins of the United States were analyzed during the period of August through November 1979. The three basins include the Hanna Basin of Wyoming, the North Park Basin of Colorado and the Southern Anthracite Field of Pennsylvania.

Jan 1, 1980

The first metal-mine accident-prevention course was prepared and published 1942-45 as a series of seven miners' circulars (Nos. 51-57). The course has been broadened, revised, and brought up to date and is being published as a similar series of seven miners' circulars on accident prevention at metal and nonmetallic mines. These circulars are: 1. Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1957

By Wilbert J. Huff, Raymond H. Moore

"Black powder is employed widely in peace and war. Its properties are therefore of considerable interest to many. The Bureau of Mines frequently is asked to furnish information on its use and safe handling in the mining and mineral industries in times of peace and is now engaged in studies of its application to the arts of war.Black powder has been the agent in many accidents - some very disastrous - and its handling and use are deemed very hazardous. The belief is widespread that the hazards are due principally to the ease with which the powder is ignited by a hot spark or flame in contradistinction to high explosives; these usually are ignited only with difficulty, and some burn incompl0tely and to a certain extent are self-extinguishing. Primary precautions, .therefore, should be taken to prevent the access of heat, spark, and flame.In black powder manufacturing operations a frequent source of disaster is the initiation of fires and explosions in the wheel mills in which the sulfur, charcoal, and nitrate are incorporated. Long experience has indicated that the wheel mill probably will fire if the powder is not kept moist enough; manufacturing supervision calls for the maintenance of a minimum moisture content, at least during the milling. Accidents occur elsewhere in the manufacturing line, and in an endeavor to minimize these, particularly those happening in corning mills, one of the writers suggested many years ago that a suitable humidity be maintained in other operations in the hope that it would serve protectively as in the wheel mill. The experience of one company for many years with this practice was favorable. It seemed desirable therefore, to explore the question experimentally."

Nov 1, 1944

By R. A. Beall

This paper summarizes the development of a furnace for producing titanium castings. The general problem is outlined and chronological details are given on the construction and operation of four different casting furnaces, all utilizing consumable-electrode arc heating and water-cooled copper crucibles. Of the two methods of pouring, the tilt-pour technique has been more satisfactory than bottom tapping. Mold design, electrode fabrication, and deep-pool production are discussed. INTRODUCTION In the early summer of 1953 the Bureau of Mines was contacted by the Department of the Army through Watertown Arsenal to explore the possibility of conducting research on casting titanium metal. The objective of the program was "to develop a technique for producing formed castings of titanium metal not less than 40 pounds in weight and without introduction of deleterious contamination."

Jan 1, 1956

By P. L. Weston

The Bureau of Mines used high-temperature reduction roasting, magnetic separation, acid-leaching, and autoclave precipitation processes to recover iron and manganese from brown Cuyana range ores of Minnesota. Wet magnetic separation concentrated over 90 percent of the iron in 3 of 4 ores as high grade products analyzing 74 to 85 percent iron, 2.5 to 6 percent manganese, and 3 to 10 percent SiO2. The nonmagnetic fractions were leached with dilute sulfuric acid extracting 83 to 93 percent of the contained manganese and small amounts of iron. The leach solutions contained Mn-to-Fe and Mn-to-SiO2 ratios favorable enough for possible consumption in metallurgical mane operations. Exceptionally pure Mn solutions were achieved by pressure precipitation of the remaining iron in an autoclave followed by lime precipitation of silica and alumina.

Jan 1, 1966

By S. C. Termes, P. E. Richardson, R. L. Wilfong

"The Bureau of Mines conducted research on the flocculation of various minerals with insoluble cross-linked starch xanthate (ISX) to determine its potential as a beneficiation technique for low-grade, highly disseminated ores and for selective desliming. Covellite, chalcocite, pyrite, pyrrhotite, chalcopyrite, bornite, sphalerite, galena, and molybdenite fines flocculate with ISX. Floc formation, floc size, and settling rate are dependent on pH, with the pH dependence differing for each mineral. Quartz is not flocculated by ISX. Experiments to obtain selective flocculation of sulfides from quartz were attempted. Good selectivity was only obtained for the bornite-quartz system. Post flocculation separations resulted in flocculated bornite in grades as high as 92 pct. Evidence is presented that the flocculation of many of the sulfide minerals with ISX may involve covalent bonding of the xanthate group to lattice metal site(s). INTRODUCTIONBecause of the increasing interest in selective flocculation as a beneficiation technique for low-grade, highly disseminated ores and for selective desliming, the Bureau of Mines has been investigating the flocculation behavior of several cross-linked starch derivatives containing chelating groups. This report dis cusses the flocculation of sulfide mineral fines by insoluble cross-linked starch xanthate (ISX).Polymeric materials such as ISX, which contain a chelating group of known re¬activity towards specific mineral surfaces, were first proposed by Slater, Clark, and Kitchener (1), 3 Kitchener (2), and Attia and Kitchener (3) as selective flocculants for mineral fines with particle aggregation possible through a bridging mechanism. ISX appeared to be attractive as a sulfide mineral flocculant because (1) alkyl xanthates are known to react selectively with sulfide minerals"

Jan 1, 1983

By D. C. Dahlin

The Bureau of Mines has investigated podiform chromite deposits in three ultramafic bodies in the Caribou Mountain and lower Kanuti River areas of central Alaska. The investigation, reported in two parts, was done as part of the Bureau's mission to help insure an adequate supply of minerals to meet the Nation's needs. Part I describes an extensive field investigation and mineralogical studies by personnel from the Bureau's Alaska Field Operations Center. This report, part II, describes the mineralogy of 11 samples that were high-graded from surface exposures at 10 sites and presents the results of laboratory batch beneficiation tests designed to concentrate the chromite. The 11 samples, peridotites and chromitites that consisted of variable amounts of chromite or chromium-bearing spinets, olivine, and serpentine, were beneficiated by grinding and sizing, gravity concentration, and electrodynamic separation. Three high-chromium chromite concentrates, two high-iron chromite concentrates, and one high-aluminum chromite concentrate were produced. Three other concentrates were marginal, and two were submarginal. Chromium recoveries ranged from 54 to 92 pct. These results indicate that the areas may be significant chromium resources. Potential platinum association with the chromite was also investigated. Analysis of these 11 samples indicates that the areas are not good platinum resources.

Jan 1, 1983

By H. S. Auvil, L. D. Schmidt, H. G. Graham

"Several studies on the bulk density of coals prepared for byproduct-oven use were undertaken during the war by the Bureau of lanes in cooperation with the Office of the Solid Fuels Administrator and with the advice of the Coke Production Committee. The primary purpose of these studies was either to produce more uniform coke or to increase the throughput of existing facilities or both; the goal was increased Production of steel for war. As these studies were made, detailed reports were sent to the individual companies with whom the Bureau cooperated; also two reports,5/6/on the general subject of bulk-density control were published. In the course of the work, data were gathered that now prove of value in judging the merit of carious methods of testing bulk density and the limits of application of each method in byproduct-oven operations.Since the cessation of hostilities, the .Bureau section (Coke Production Survey Section) that conducted this work has been liquidated, but it was felt advisable to prepare a report on the accumulated experience so that it would be in a form available for the use of the industry and also as a base for any further research on the control of fluctuating bulk densities in coke ovens.It is hoped that the data and experiences recorded herein will be of material assistance to the many who have had difficulty in obtaining reproducible results in bulk-density testing. Since the data were gathered in the course of extending aid to individual plants in minimizing the deleterious effects of fluctuations in bulk density of oven charges on the quality and quantity of coke produced, certain desirable phases of an over-all investigation were not covered. However, on certain of these phases qualitative indications are available and the policy followed herein is that suggested by the American Society for Testing Materials Manual on Presentation of Data7/ that lacking quantitative information, relevant material should be included even though it ""may be qualitative in character, some may even be vague."""

May 1, 1946

By John G. Palmer

Continued development of an especially impregnated silica gel capable of reversible chemical detection of carbon monoxide (CO) was reported. The affects of changes in mine-related ambient conditions on the detection catalyst's response were explored. Temperature, humidity, and several interfering gases were found to affect the detection catalyst. The interferents include hydrogen sulfide, nitrogen dioxide, acetylene (and methylacetylene), and ammonia. High humidity decreased the detection catalyst's sensitivity to carbon monoxide for some formulations. Increasing temperature generally decreased the reaction time of the detection catalyst with carbon monoxide. Badges and carriers for the visual presentation of the detection catalyst were constructed. Several variations of these devices included provisions for absorbants and filtering agents which help protect the detection catalyst from gaseous interferents. A variety of catalyst support agents were tested in an effort to find the most suitable. Included were alumina, magnesium oxide, magnesium silicate, and several forms of silica gel. In addi tion to free-flowing forms of these sorbents, thin layer chromatography plates coated with cellulose, alumina, and silica gel and newly developed PTFE entrained silica gels were examined. A limited physical, chemical, and mechanistic characterization of the detection catalyst and the materials used to prepare it has been carried out. Metal component ratio studies, spectral, analytical, pH, and rate measurements were done.

Jan 1, 1982

By Forrest T. Moyer

The safety record of the coal-mining industry in 1968 worsened appreciably .in fatality experience but was slightly better in nonfatal-injury experience. Work fatalities in 1968 totaled 311 and occurred at a frequency rate of 1.33 per million man-hours or worktime. The fatality total was 89 higher, and the rate of occurrence was 45 percent higher than the corresponding figures of 222 fatal injuries with a frequency rate of 0.92 in 1967. The worsened fatality record in 1968 resulted primarily from two major disasters (a single accident which results in the death of five men or more) which killed 87 men, nine in one and 78 in the second. The total of 9,639 nonfatal injuries was the lowest annual figure in complete records back to 1930. The frequency rate of 41.12 nonfatal injuries per million man-hours of worktime for 1968 was the second lowest annual rate of occurrence. The severity rate of all injuries, 10,513 days lost or charged per million man-hours, and the average severity, 248 days lost per injury, in 1968 were the worst annual data in the series started in 1944. Total worktime of 234.4 million man-hours and coal output of 553.3 million tons in 1968 were, respectively, 3 and 1 per- cent lower than in 1967.

Jan 1, 1972

By Thomas E. Finch

This report is an engineering-economic evaluation of alternate methods of handling the parting between two coal seams. It consists of evaluations of parting stowing techniques applicable in a representative, thick seam western United States mine. Methods are examined for their potential implementation, and an estimated operating cost per yard of material moved is developed. The methods are of two categories castback or haulback. Haulback methods use truck haulage except With scrapers, and the castback methods are a direct stowage with no intermediate haulage equipment. Possible equipment combinations include draglines, shovels, hydraulic backhoes, bucket wheel excavators, scrapers, and front end loaders. The purpose of this report is to evaluate the effective competetiveness of the various alternatives.

Jan 1, 1975

This Bureau of Mines report concerns two subjects important in the application of electric power in mining systems. Electrical transients and their suppression are discussed, and several considerations are explored with regard to the use of explosionproof or other electrical enclosures.

Jan 1, 1979

By James J. Dowd

The investigation to evaluate the reserves of coking coal in the United States suitable for the manufacture of metallurgical coke is being made by the Bureau of Mines in three parts: (1) To estimate known measured and indicated recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and (3) to study the carbonizing properties of coals and coal blends not now widely used for metallurgical coke making. This is the eighth of a series of reports giving the results of studies by counties under part (1) of the investigation. (See appendix.) This report covers Jefferson County, Pa., which comprises parts of Marienville, Hallton, Ridgway, Brookville, DuBois, Penfield, Smicksburg, and Punxsutawney quadrangles. (See fig. 1.) A short resume of the chemical and carbonizing properties of the coals is included. Data on the coal beds in the county were obtained from mining companies, land companies, individual landowners, and other sources of authentic information. A base map for each bed in each quadrangle was made to the scale 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds 0 to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick, These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas, areas excluded from the estimate, and areas outside of the outcrop were measured by planimeter on the base maps. Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1952