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By J. F. Barkley

As part of the work of serving as Chairman of Subcommittee 3, Health and Industrial Requirements, of the American Society of Mechanical Engineers' Committee on Air-Pollution Controls, the author assembled the following information on accepted maximum permissible concentrations of air pollutants from the standpoints of health, damage to vegetation, damage to property, and requirements of industrial processes. A search in technical literature was made followed by direct inquiry to all State governments as to their regulations. The subcommittee membership - G. D. Clayton, senior sanitary engineer, Public Health Service, United States Department of Health, Education, and Welfare, Detroit, Mich., Dr. L. Greenburg, commissioner; Department of Air Pollution Control, New York, N.Y., Dr. M. Katz, Defence Research Chemical Laboratories, Ottawa, Ontario, Canada, and Dr. H. H. Schrenk, research director, Industrial Hygiene Foundation of America, Inc., Mellon Institute, Pittsburgh, Pa. - reviewed the information and made very helpful comments and corrections.

Jan 1, 1954

Avoid accidents that can occur when applying belt dressing from an aerosol can, particularly when can pressure has dropped or when spraying against wind. Approach Use a garde-type sprayer. How It Works Commercially available garden-type sprayers can be used for applying conveyor belt dressing from 12 feet away, or more. Pressure is easily raised and maintained at about 50 psi. Most sprayers have a hand pump, but a battery-powered cordless model is also available. Garden-type sprayers are available in various sizes from 11/2 to 18 gallons, with the larger models wheel mounted. The 3-gallon model evaluated by the Bureau has a shoulder carrying strap, which gives additional safety advantages. Use of the strap frees both hands for climbing ladders or holding onto catwalk rails. When spraying, one hand can remain on a handhold to lessen the chances of touching a moving belt.

Jan 1, 1980

Develop a safe, nonpolluting power source for underground mining equipment. Approach The Bureau of Mines and EIM-CO Mining Machinery International entered into a cost-shared project to develop and demonstrate a novel power source for mining. An underground mining utility truck was equipped with an ultra-low-emission hydrogen-fueled engine and a safe, metal hydride fuel storage system. How It Works The nonpolluting hydrogen engine and a "solid-state" (metal hyride) hydrogen fuel storage system were combined to power a utility mining vehicle. An 85 horsepower diesel engine was convened to burn hydrogen. The engine was converted by equipping it with a spark ignition, lowering the compression ratio, turbocharging, and adding an ahercooler and a parallel fuel induction system. Parallel induction provides two intake paths, one for hydrogen and one for air. It avoids intake-manifold backfiring by keeping the hydrogen and air separate until they enter the cylinder.

Jan 1, 1986

By Dana Reinke, William Wiehagen, Launa Mallett, Charles Vaught, Kathleen M. Kowalski, Michael J. Brnich, Lynn Rethi, Lisa Steiner

Safety and health professionals from all sectors of industry recognize that training is a critical element of an effective safety and health program. A major concern in the mining industry today is how to train the present aging workforce plus the expected influx of new and less experienced miners and mine operators as the cohort of older workers retire. This paper defines the problem, offers a model to structure the inquiry, and presents the key issues a multi-disciplinary team of NIOSH researchers identified, based on an extensive review of the current literature in relevant areas. Issues include differences between cohorts, such as the newer workers (Generation M), and present workers (Boomers) with respect to their physical, social, psychological, and cultural characteristics, their learning styles and work expectations. Specific issues for an aging workforce are discussed. Some preliminary recommendations are offered on the type of training needed.

By J. R. Thoenen

[Since the publication of the preliminary report on this subject in July, 1927, (The Wire Saw in Slate Quarrying, Preliminary Report, Serial No. 2820, by Oliver Bowles) the wire saw has been in constant daily operation at the quarry of the Colonial Slate Company. Luring this time between twenty end thirty successful cuts have been made varying in length from forty-five to ninety-two feet and in depth from six to ten feet. No accurate time records have been kept on these cuts but they have totaled over 12,000 sq. ft. of area and required 19,000 lineal fact During these cuts the average speed of cutting has risen from the 12.8 sq. ft. per hour obtained in the original recorded tests to between 15 and 20 sq. ft. per hour, with the present rate running very close to 20 sq. ft. per hour at this quarry.]

Jan 1, 1928

By D. R. Tesarik, M. K. Larson, J. P. Dunford, E. G. Zahl

Western coal mines are operating under increasingly challenging ground conditions. Researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health are cooperating with mines to evaluate how these conditions affect mine opening stability and related miner safety. A system was developed to monitor rock and coal stresses during mining of an entire longwall panel. The system was designed to generate data in near real time to evaluate rock behavior in roof strata and the onset of hazardous conditions as overburden stress was redistributed over working entries during gob formation. Computer simulations and in-mine evaluations were used to optimize instrument placement. A prototype packer assembly was designed and tested for installing sensitive instruments in a mine roof. This paper provides background information on the stress monitoring concept and focuses on the development of instrument placement techniques and the prototype packer assembly.

Measure the leakage through individual crosscut stoppings quickly and economically so that the worst ones can be identified and repaired. (Typically 60 to 80% of the air supplied to a mine short circuits before reaching a working face.) Approach Most of the leakage through a permanent stop-ping is channeled through two windows in a temporary stopping, and air velocities through the windows are measured; leakage is determined from a formula. How It Works A temporary stopping made of plastic brattice is erected in the same cross cut as the permanent stopping, either upstream or downstream. The brattice is fastened to the roof, bottom, and ribs of the entry with spads. Normal leakage of brattice was allowed for in deriving formula, and does not effect results. For best accuracy the brattice and the stopping should be separated by a distance of one hydraulic diameter.

Jan 1, 1979

? A roof bolter reaches for a lever while guiding the drill with his other hand. Since he's watching the drill and many of the controls look and feel alike, he hits the wrong control and crushes his hand. ? Six hours into the night shift, an ore truck driver dozes off. The truck plows over the berm and down into the pit. ? Fleeing a afire, a face crew sees smoke in the intake entry. Assuming the fire is ahead, they cross over to another entry, but soon encounter even worse smoke. These very different accidents have at least one factor in common: the human factor. The actions, decisions, thoughts, or perceptions of one or more humans contributed to the accident. These are just a few examples of safety problems researched by the Human Factors Group of the Pittsburgh Research Center, U.S. Department of Energy.

Jan 1, 1998

By O. C. Ralston, L. H. Duschak, R. D. Pike

Much detailed information on the production of plastic magnesia from magnesite mined near Chewelah, Wash., was accumulated during a cooperative investigation conducted by the Bureau of Mines and the Northwest Magnesite Co. at the laboratories of the University of California in 1919-1921. This bulletin gives mainly the results of the work done with Chewelah magnesite, supplemented by data on similar work with other magnesites, particularly those of California, in the endeavor to produce a plastic magnesia that would be satisfactory for making the so-called " Sorel" cement composition flooring, stucco, and plasters. As standardized methods £or testing such compositions did not exist, it was necessary to examine carefully the various methods in use and choose those that seemed appropriate. In consequence, this report contains many tests made by the methods selected and can be used £or reference by those who wish to adopt standard methods of testing.

Jan 1, 1925

By Launa G. Mallett, Barbara Fotta

This report examines the effects of mining height on injury rates in U.S. underground nonlongwall bituminous coal mines, controlling for both the employment size of the mine and the mining methods. Using the mine-level employment and injury data reported to the Mine Safely and Health Administration, mines were stratified by average coal seam height (<43 in, 43-60 in, and >60 in) and by the average number of employees working at the mine (<20 employees, 20-49 employees, 50-99 employees, and >99 employees). To reduce the confounding effects of mining method on injury rates, mines using longwall mining methods were identified and excluded from analysis. The employment data show that as the mine size increases, the proportion of hours worked in low seams decreases substantially. Additionally, miners injured in small, low- scam mines arc, on average, younger and less experienced than those injured in large high-seam mines. Nonfatal disabling and fatal injury rates were computed within each category of employment size and seam height for the major types of accidents (ground falls, powered haulage equipment, machinery, handling materials, slips and falls, and hand tools). Our findings suggest that, regardless of the employment size, as mining height increases, miners are at increasingly higher risk of injury from accidents due to slips or falls and accidents involving shuttle cars and falls of ground. As mining height decreases, miners are at higher risk 01 injury from accidents involving roof bolting machines, load-haul-dump types of powered haulage equipment, personnel carriers, and powered haulage conveyors. On the other hand, regardless of the height of the coal seam, miners working in large underground mines had higher rates of injuries resulting from accidents involving handling materials and nonpowered hand tools, but lower rates of injury from accidents involving continuous mining machines and lower rates of fatal injuries from falls of supported and unsupported mine roof. Finally, miners working at small mines in low or medium seams are at higher risk of being fatally injured by a ljll of unsupported mine roof. These findings suggest the importance of&apos; considering the working height of the mine, as well as the employment size of the mining operation, when developing intervention strategies to reduce injury risk to underground coal miners. Results also identify the need to further explore how mining height contributes to the frequency and severity of injuries.

Jan 11, 1997

By R. N. Roby

"INTRODUCTION A preliminary examination of the Green Monster and Benich copper prospects was made by engineers E. W. Newnan and George N. Bennett, of the Bureau of Mines, on December 13, 1943. In an unpublished report, it was stated that certain geologic features appeared to be similar to those associated with the copper deposits of the nearby Butte district. On these premises, a preliminary diamond-drilling program was recommended to explore 300 to 400 feet below the mineralized outcrops for the possible presence of a sulfide enrichment zone. In accordance with that recommendation, three holes were drilled. This report presents the data provided by that preliminary drilling exploration.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell D. Moon, chief, conducts preliminary exminations, perform the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyses samples and performs beneficiation tests.The field work on the Bull Run exploration project was supervised byE. W. Newman engineer in charge of the Helena field office. The chemical analyses and assays included in this report were performed under the direction of A. C. Rice, acting engineer in charge, Bureau of Minos Rare and Precious Metals Experiment Station at Reno, Nev. The diamond-drill cores were logged by geologists of the Federal Geological Survey."

Mar 1, 1947

By Wilbur I. Duvall

Nineteen quarry blasts were instrumented with particle-velocity gages mounted in a uniform soil overburden, back of one face in a quarry in Iowa. Three components of particle velocity, radial, vertical, and transverse, were recorded at each of eight stations back of each blast. Distances from blast area to gage stations ranged from 150 to 3,000 feet. Eleven of the quarry blasts employed millisecond delays, and eight were instantaneous blasts. Charge weight per hole was 200 pounds, and the charge weight per delay interval, including the instantaneous blasts, ranged from 100 to 3,000 pounds. Analysis of the data from these tests shows that the particle velocity, V, produced at distance, D, by a quarry blast of charge per delay interval, W, can be represented by an equation of the form, V=KWb D-n, where b and n are exponents, and K is the intercept constant which is a measure of the level of vibration. The value of K for a millisecond-delayed blast employing one hole per delay interval is about 42 percent larger than the value of K for a single-hole blast. The value of K for a multiple-hole milli-second-delayed blast is about the same as that for an instantaneous blast when the charge per delay for the millisecond blast is equal to the total charge for the instanteneous blast. The vibration level from millisecond-delayed blasts employing one hole per delay is shown to be independent of the length of the delay interval and the number of delay intervals over the range of the variables tested: 9, 17, and 34 milliseconds and 3, 7, and 15 delays per blast.

Jan 1, 1963

By D. C. Fleck

The Bureau of Mines, in a cooperative research program with four lead companies, has investigated ferric chloride leaching of galena to prepare lead chloride for molten-salt electrowinning to produce lead metal. The hydrometallurgical-electrolytic process is an alternative to the sintering-smelting-refining process currently used to produce lead metal and avoids the environmental problems associated with a conventional smelter. During investigations on the electrowinning aspects of the work, it was noted that certain cations, moisture, and sulfate in the electrolyte affect lead metal purity, cell voltage, current efficiency, and viscosity of the electrolyte. Results of bench-scale tests are re-ported on the effects of CaCI2, CuCI2, FeCI2, MgCI2, NaCI, ZnCI2, PbS04, and moisture on electrolysis. As impurities increased in the electrolyte, current efficiency decreased. CaCI2, CuCI2, and FeC12 decreased current efficiency by 12 to 47 pct. ZnCl2 gave a small voltage increase, while CaCI2 addition equivalent to 4.9 pct Ca caused a 50-pet increase in voltage. The lead metal was contaminated in direct proportion to the CuCI2 buildup in the electrolyte, Anode corrosion was observed with MgCI2 and MgC12?6H20. Viscosity increased appreciably with the buildup of NaCI, CaCI2, and sulfate. Electrolyte foaming occurred with ZnC12, MgC12?6H20, MgC12, FeC12?2H20, and FeCI2. Moisture inhibited the coalescence of the lead metal.

Jan 1, 1983

To develop and design a bit that will rapidly drill smooth and precise instrumentation holes in soft rock. Approach Use a one-piece bit made by combining a drag bit and a diamond bit. Because a smooth-walled borehole with a precise diameter is needed for borehole pressure cells (BPC) and other borehole instruments, a diamond bit is usually used. However, diamond bit drilling is slow, and the bit will tend to bind when squeezing ground is encountered. On the other hand, the drag bit will cut faster, but the walls of the drill hole will be rough and the diameter will not be as precise. The combination will provide a bit which penetrates as rapidly as a drag bit, but retains the smooth-wall and precise borehole diameter of a diamond bit. How It Works A three-foot-length of EW-size drill rod is centered in a diamond bit by welding it to three equally-positioned spacers at each end of the bit. A drag bit is attached to the EW rod with a standard EW-to-drag bit adapter as shown in the diagram. Three equally-spaced diamond inserts are set to the desired hole size and welded to the diamond bit barrel behind the crown. These inserts increase the smoothness and precision of the hole by cut-ting away any hole closure. Three equally-spaced shims are set approximately 0.020-inch under the overall insert diameter size and welded to the rear of the diamond bit barrel. The combination bit should be used on a diamond drill with either water, mist or air as the coolant.

Jan 1, 1982

By an Slo, J. J. Forbes

"INTRODUCTION This is the first of a series of information circulars dealing with the control of roof and the prevention of accidents from falls of rock and coal. These circulars are being published to focus attention of the coal-mining industry on this most prevalent source of fatalities and injuries and to present factual information that should be helpful in reducing loss from these causes.Records of fatal accidents in the coal mines of the United States, from all causes, have been kept since 1906; during this period approximately 30,000 men have been killed by falls of rock and coal in the bituminous-coal mines, and more than 7,000 men have lost their lives in the Pennsylvania anthracite mines from the same causes. From 1906 to 1930, about 900 men were killed annually by falls of rock and coal in bituminous-coal mines, and about 200 men were killed annually in anthracite mines during the same 25-year period. From 1931 to the present time, the number killed annually from falls of rock and coal has averaged more than 500 men in bituminous-coal mines and about 125 men in Pennsylvania anthracite mines.Numerically the record of accidents from falls of rock and coal shows improvement, but on a percentage basis and on a million-man-hours-of-exposure basis little, if any, improvement has been made during the past 40 years. The cold fact is that, year after year, about 50 percent of all those killed in coal mines in the United States lose their lives from falls of rock and coal."

Apr 1, 1948

By J. L. Ellenberger

The National Institute for Occupational Safety and Health (NIOSH) has continued the research role of the former US Bureau of Mines (USBM) to engineer techniques that will reduce the hazards in the mining workplace associated with coal bumps. Recent research focused on a longwall coal mine in Utah with overburden greater than 750 m (2,500 ft) containing several massive sandstone units. The primary field instrumentation at the site was three-dimensional, full waveform, autonomous microseismic arrays placed underground and on the surface in order to surround the active multi-panel longwall district. The purpose of these arrays was to help investigate the strata mechanics associated with the redistribution of stress and the associated gob formation of the longwall. Specifically, the seismic arrays were used to determine the timing and location of the failure in the strata surrounding the active mining. Overall 13,000 seismic events were detected and located with on-site processing during the five months the panel was being mined, including a magnitude (ML) 4.2 event. Of these, a smaller subset of 5,000 well-located events was selected during post-processing to form a consistent data set for analysis in this paper. From this data set, it was observed that the seismic events generally occurred in advance of the longwall face, both above and below the panel, consistent with failure of the strata in the forward stress abutment zone. Also, the occurrence of the ML 4.2 seismic event within 150-180 m (500-600 ft) of a deep cover longwall face with no associated bump caused a re-evaluation of the nature of the connection between seismic activity and coal bumps.

Jan 1, 2002

By D. Harringtong

"There has been much writing and argument on the subject of giving bonuses to miners, quarrymen, metallurgical and chemical workers, and others as a stimulus for safe work and for work safely done. Theoretically, everyone should be careful and should not need monetary or any other type of encouragement for the prevention of accidents; as a. fact, few people are careful, and this is primarily the reason way many if not most accidents occur. A bonus, however, is not simply money given away by an employer; it must be earned, so to speak, before it becomes due; in other words, if the standard established is not reached, no bonus is paid, and in many cases some disciplinary action is taken.The United States Bureau of Mines Is asked from time to time for suggestions for rewards to mine workers who have a good attitude toward working safely or who need some stimulus to cause them to make greater or more earnest efforts toward safety for themselves and their co-workers. A recent inquiry prompted the collection of data on some safety bonus systems from reports of this bureau's field engineers and others, and some of these Now given. Bonus practice at both coal and metal mines is included because a system used at metal mines is generally adaptable to coal mines; in fact, in numerous cases, bonus systems recently started at some coal mines are based on systems in vogue and giving satisfaction some metal mines; in-some instances, also, metal mines have been able to get good suggestions from coal mines or from the cement or petroleum industries. it .should be understood that a bonus, even as applied to the encouragement of safety, does not necessarily mean payment of money; in fact, some successful bonus systems have in them no direct money exchange; hence, the bonus as treated in this paper is that defined as ""Something given in addition to what is ordinarily received by, or strictly due to, the recipient.""Acknowledgment is given here to members of the safety division of the Bureau of Mines who sent in some of the information here presented; to the Engineering and Mining Journal and Mining Congress Journal, from which some items were abstracted; to various mining officials who gave data in one form or another; and to M. von Bernewitz, of the United. States Bureau of lines who aided in framing parts of this paper."

Jun 1, 1932

By Edward Cogan

Equilibrium phase diagram studies of zirconium- rare earth metal alloys by the Bureau of Mines at its Albany Metallurgy Research Center prompted the development of a rapid gravimetric method for determining rare earths in zirconium in which the rare earths are absorbed from sulfuric acid solution of the alloy on a cation exchange resin . The sample in 10 percent H2SO4 is introduced into the column , the zirconium is eluted with 10 percent H2SO4 , and the rare earths are eluted with (NH4 )2SO4 solution and precipitated with NH4OH . A tracer technique was employed to determine the efficiency of the procedure . Y203 and europium 154 - 152 (Oak Ridge ) were added to 10 g of zirconium and taken through the entire procedure . Recovery averaged 97.6 percent on 0.002 μg europium in the rare earth fraction . Rare earths were determined in the range 0.10 to 90 percent .

Jan 1, 1964

By Oliver Bowels

Many inquiries are received by the United States Bureau of Mines for the names of elementary books on geology, mineralogy, methods of identifying minerals, prospecting, and similar subjects. In response to this demand the following brief bibliography has been prepared. As many of the inquiries are received from those who have limited technical knowledge of the subjects involved, the bibliography includes the simpler texts which present the subjects in nontechnical language. Other texts contain glossaries which define the technical terms used. A short note following the title indicates the character of each book, the number of pages, and the price. Thus, elementary mineralogists or geologists, prospectors, mineral collectors, nature students, or travellers may select the texts that best suit their requirements and their capabilities. To supply the needs of more advanced students, quite a number of the standard texts used in schools and colleges are included in a second group. A short list of books on economic geology and mineralogy has also been added.

Jan 1, 1929

By Thomas J. Peters

The U.S. Bureau of Mines conducted a mineral investigation, and the U.S. Geological Survey did a geological appraisal of an east portion of the Bear-Marshall-Scapegoat-Swan (BMSS) RARE II area (No. A1485) to provide mineral resource information for land use planning. The Bureau of Mines&apos; investigation consisted of a library and field search for all mineral properties and occurrences, and included a review of Teton County mining claim records. Those records showed two placer claims, the only mining-related activity known in the area. Six reconnaissance pan samples were taken in the vicinity of the two placer claims, the Lone Star and Spotted Horse, located on Hannan Gulch in 1900 and 1901. One sample contained a trace of gold, but there are no identified resources. However, the study area is in the Rocky Mountain Overthrust Belt, which is productive for oil and gas elsewhere. The entire study area is blanketed by oil and gas leases and is currently being explored.

Jan 1, 1983