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By Bruce K. Cantrell, Winthrop F. Watts

The U.S. Bureau of Mines and others have conducted a number of occupational exposure surveys since the publication of the International Agency for Research on Cancer report of 1989(1), which labeled diesel exhaust as a probable human carcinogen. These surveys have assessed diesel exhaust exposure using measurement of diesel aerosol and/or specific polycyclic aromatic hydrocarbons as indicators of exposure. This report reviews, available diesel exhaust aerosol and gas measurement techniques. Measurement of human exposure to toxic agents is the first step in determining the exposure-dose-response relationship. It is a fundamental step in risk assessment. Measuring exposure to diesel exhaust pollutants is particularly challenging due to the complexity and variability of exhaust components. This paper reviews current occupational health standards for diesel emissions and available diesel exhaust gas and aerosol measurement techniques. Although surveys in mines have primarily assessed diesel exhaust exposure using diesel particulate matter (DPM) some exhaust gas measurements have been used as indicators of exposure. DPM is emphasized because it is a major component of diesel exhaust, is suspected to make a major contribution to the health hazard, and is measurable. OCCUPATIONAL HEALTH STANDARDS Occupational exposure surveys of diesel exhaust frequently measure regulated pollutants, or pollutants that are suspected carcinogens, even if no permissible exposure limits (PELs) have been established. In the United States, various organizations recommend a range of allowable values for diesel exhaust gaseous constituents, including carbon monoxide (CO), carbon dioxide (CO2), sulfur dioxide (SO.), nitrogen dioxide (NO2), nitric oxide (NO), and formaldehyde (HCHO). Table I summarizes these recommended levels, showing 8-hour or 10-hour time-weighted-average values where available; where these are not available, 15-minute short-term [ ]

By By Staff

"This publication summarizes, for potential contractors and all other interested parties, the research, development, and demonstration of in-house and contract projects programmed by the Bureau of Mines for fiscal year 1982(October 1, 1981-September 30, 1982) under its Minerals Health and Safety Technology program. The objective of these projects is to provide an ordered and sequenced series of advance toward the Bureau's overall goal of providing the systems technology required to create a more healthful and safer working environment for the Nation's mining and minerals processing workersINTRODUCTION The Bureau of Mines conducts a balanced, continuing in-house research and development program to accelerate systematic improvements in health and safety conditions in U.S. mines. Part I of this report outlines the Bureau's present in-house effort to all interested parties; in particular, potential contractors can refer to it when submitting USP's (unsolicited proposals), thus avoiding proposing research that duplicates work being performed by the Bureau.It is the policy of the Bureau of Mines to utilize as fully as possible the capabilities of the private sector in minerals research, and to that endPart II of this report outlines the Bureau's current projected contract research needs.The projects presented were planned at the beginning of the fiscal year and are subject to change based on emerging priorities and availability of funds. Contingencies may require that a significant portion of the program be deferred into fiscal year 1983 (FY 83) or beyond. It is important to realize that since this is a summary document, the project descriptions related to a design, fabrications, and demonstration effort do not necessarily imply total package procurement."

Jan 1, 1982

By L. R. Burdick

The Smokescope is an instrument recently developed for determining the density of smoke by shade comparison. The instrument is designed so that the smoke is seen adjacent to two shades of gray corresponding to Nos. 2 and 3 on the Ringelmann chart. Data on smoke density are important in the smoke-abatement field. The method that is specified and accepted as standard for smoke-density determination by the majority of city smoke regulations involves comparing the smoke shade with the four shades on the Ringelmann chart as published by the Bureau of Mines.2/ This investigation was made to determine the accuracy and convenience of the Smokescope. It was conducted as a part of the Bureau I s air-pollution work, which includes the study of techniques that will promote smoke abatement. The accuracy of the Smokescope was arbitrarily defined as the difference between the Smokescope determinations and the determinations by the accepted, standard method and was expressed as Smokescope correction. Although the corrections obtained were strictly correct only for the two observers and the Smokescope of the investigation, they indicate what might be expected from any observer who uses a Smokescope with reference shades that duplicate those of the test instrument. The report is devoted largely to the data on Smokescope correction, which were taken from a single stack under controlled smoke conditions. Field work, which was done at various locations with different stacks, is mentioned briefly in connection with the comparison of the convenience of the two methods. The data for estimating Smokescope correction were taken for the three variables that were expected to affect the results, namely, the density of the smoke, the amount of light, and the color of the sky behind the smoke.

Jan 1, 1955

By M. J. Ferrante

Low-temperature heat capacities and high-temperature enthalpies were determined calorimetrically for Na2Cr04, A reversible transition was found at 700° K with an isothermal heat of transition of 2,263 cal/mole. High-temperature X-ray diffraction analysis showed that the transition was a crystal change from the low-temperature orthorhombic form to the high-temperature hexagonal form. At 795° K the hexagonal form had the parameters a, = 5.691 and co = 7.478 A. Powder diffraction data for the high-temperature form are given and possible structures discussed. The melting point was determined to be 1,065° K with a heat of fusion of 5,810 cal/mole. Enthalpy and entropy increments from this investigation were combined with other data from the literature to calculate enthalpies of formation, free energies of formation, and equilibrium constants of formation from 298° to 1,400° K. Equations that represent enthalpies above 298° K are given.

Jan 1, 1972

By G. T. Lineberry, W. J. Wiehagen

This paper discusses a practical method for enhancing the performance of mining work crews. The method, described as the Work Crew Performance Model (WCPM), seeks to define performance variability within similar tasks of an underground work crew. Key components of the WCPM include: (I) job definition through task analyses; (2) the ranking of job elements by perceived cost consequence; (3) observational techniques to establish performance baselines; and (4) cost linkages between adherence to task procedures and measures of consequence for noncompliance. The components of this model emphasize a reliance on learning from a veteran work force and using that information to reinvest in strategies to enhance safety and efficiency. These strategies are not limited to technologic efforts but include consideration of the so-called "soft-skill technologies" aimed at reducing variability in individual performance and at effecting a continuous improvement in overall system effectiveness.

By Carlton E. Brown, William P. Yant

"INTRODUCTION Direct visual microscopic determination of particle-size distribution and number concentration of atmospheric dust is time-consuming and trying to the eyes. By using the microscope to project images of the particles at high magnification onto a screen much of the eyestrain can be eliminated and particle-size distribution results obtained with less effort and at a considerable saving in time. It also permits simultaneous observation of the images by more than one person. Microprojection requires no more skill and very little more apparatus than is required in the use of the microscope. Anyone familiar with the microscope should be able to obtain as perfect images on the projection screen as in direct visual microscopy since the same laws and limitationsThe theory and practice of microprojection are described in detail in texts. 5/6/ The procedure has been used and found to be satisfactory for measuring the particle-size distribution of sub-sieve-size substances, such as pigments and powder 7/8/ in the same size range as that of atmospheric dust. The Bureau of Mines has used the microprojector and found it to be quite satisfactory for (1) the determination of the number concentration of atmospheric dust R.I. 3289 in samples collected by the Owens jet dust counter; (2) particle-size distribution in samples of atmospheric dust collected by the Owens jet dust counter and by the electric precipitator; and (3) the particle-size distribution of dusts, blood cells, bacteria, and pollen. Work is in progress at this Bureau on the use of the microprojector in counting impinger samples. The use of different kinds of illumination, such as reflected (dark field), polarized, monochromatic, and ultraviolet, in the projection of images of atmospheric dust particles is being considered."

Oct 1, 1935

By J. E. Zeilinger

The technical feasibility of using energy from explosive ignitions of coal dust to pump water was .demonstrated in an exploratory investigation. Ignition of small amounts of pulverized coal that were dispersed in air over columns of water pumped up to 5.3 gallons of water per cycle when operated against a head of 30.75 feet. Water displacement was accomplished by either manual or automatic operation through a single cycle, and by automatic operation through a continuous series of cycles of I-minute duration. Operating through single cycles, slurries containing up to 3 pounds of coal and 4.6 gallons of water were also pumped. Possible uses of an efficient coal-fired pump would include pumping water for irrigation purposes, removing water from mines, transporting coal from mines in the form of a slurry, and pumping water to elevated reservoirs at electric powerplants so that it could be used to generate electricity during peak periods of demand.

Jan 1, 1966

By R. V. Ramani

This report, Volume I of the seven-volume Final Report on the U. S. Bureau of Mines research contract no. G0254030 titled Application of a Total System Surface Mine Simulator to Coal Stripping with the Pennsylvania State University provides an executive summary of the purpose and scope, objectives and results of the research. The remaining volumes of the Final Report, listed below, describe in detail model development, input and output documentation and the three case studies. Under the project, an existing surface mine simulator, Open-pit Materials Handling Simulator (OPMHS) was modified and extended for application to surf ace coal mining. In addition, two equipment selection models, and a cost model were also developed. Volume II: OPMHS User's Manual Volume III: Equipment Selection Models Volume IV: Surface Mining Cost Model Volume V: Application of OPMHS to an Illinois Mine Volume VI: Application of OPMHS to a South Eastern Ohio Mine. Volume VIII: Application of OPMHS to a South Western Mine.

Jan 1, 1978

By Donald P. Blasko

The Bureau of Mines investigated two areas of the Alaska Peninsula (Iniskin Peninsula and Becharof Lake) where oil and gas seeps were known to occur in an attempt to determine (1) whether the seeps are still active and (2) the amount of bitumen contained in the drainage leaving the seeps. The oil, water, oil-water, and gas were sampled and analyzed. Five oil samples were taken at four separate oil seeps. The API gravity of the oil ranged from 8.90 to 21.4° and the sulfur content was from 0.12 percent to 0.59 percent. Four of the seven gas samples obtained revealed fair high caloric values, ranging from 746 to 924 Btu/cu ft, and averaging 844 Btu/cu ft. A total of 44 water samples were obtained. Bitumen content of the water was as high as 9,773 mg/l at one seep, but averaged less than I mg/l where the seep-drainage water entered the Gulf of Alaska.

Jan 1, 1976

By Robert J. Timko

The objective of this Bureau of Mines research work was (1) to determine how well the E. I. Du Pont de Nemours and Company P-2500 personal dust sampling pump controls the flow rate at 2 L/min and (2) to compare respirable dust mea-surements made using the P-2500 with those made using a nonpulsating sampling flow system, both using the Dorr-Oliver 10-mm nylon cyclone dust size classifier. The calibrator and the operation manual for the P-2500, supplied by the manufacturer, were also evaluated. Flow tests consisted of long-term (6-to 8-hour) flow stability tests at various backpressures, a low-flow indicator examination, flow controller response time tests and pulsation tests. Dust tests were performed using coal, silica, and Arizona road dust. No tests were performed to examine effects of temperature, barometric pressure, vibration, or mechanical shock. These pumps performed well within manufacturer specifications in all tests.

Jan 1, 1982

By Paul S. Lewis

Bench-scale experiment~ by the Bureau of Mines showed the gross effect of retention times ranging from 0.1 to 14.5 minutes on the conversion of high-volatile C bituminous coal to liquids and gases. The uncatalyzed coal was hydrogenated at 400°, 450°, and 538° C. and 500, 1,000, and 2,000 p.s.i.g. The percent coal conversion increased rapidly during the initial 3 minutes and asymptotically approached a maximum within 7 minutes at all conditions. Reasonably good correlations of coal conversion with time, pressure, and temperature were obtained. Temperatures up to 900° C. and retention times of about 1 minute are recommended for future experiments with the objective of producing only gaseous hydrocarbons and partially devolatilized coal suitable for use as solid fuel. The reactor contained 13 semicircular ledges, and the retention time was controlled by the rotation of scrapers which swept the coal from ledge to ledge. Only coal feeds that did not adhere to the internal mechanism could be used.

Jan 1, 1961

By John C. Machisak

THIS CHAPTER of the Minerals Yearbook (Volume III) contains overall employment and injury experience for coal mines-bituminous, lignite, and anthracite; coke, petroleum and natural gas; and peat and slag plants; metal and nonmetal mines; sand and gravel operations; stone quarries; metallurgical plants, including metal mills and smelters; and nonmetal mills for 1959. Volume I of the yearbook contains injury experience and employment data in the metal, non-metal, sand and gravel, slag, and quarrying industries, and the milling operations and related plants. Volume II contains the injury experience and employment data in the fuel industries--coal, coke, petroleum and natural gas, and peat. Surveys conducted by the Bureau of Mines were the source of injury and employment data used to compile the tables and furnish information for the accompanying text. Response to the surveys was voluntary except that for coal mines. The Coal Mine Safety Act requires operators of coal mines to furnish the information requested.

Jan 1, 1960

By Joseph A. Holmes

The perpetuation of the supply of anthracite coal in Pennsylvania is a national as well as a State problem. Any investigation that shows how larger percentages of this coal may be saved in mining, without excessive cost, and without dangerous subsidence of the overlying surface ground, has a national as well as a local interest. Messrs. Conner and Griffith, who conducted the investigations described in this report largely for the city of Scranton, are consulting engineers for the Bureau of Mines for investigations similar to those they have already made in connection with their Scranton work; and this report is published by the bureau in response to numerous requests, because of the fact that the information it contains will prove useful in the general solution of similar problems in many of the country's coal fields. A study of the accompanying maps will show that the city of Scranton is underlain by 11 separate beds of coal, varying in thick- ness from 2 to 24 feet. It is estimated that before mining opera- tions were begun these beds of coal contained underneath the present city limits of Scranton 600,000,000 tons of coal. The 27 collieries operating within the city limits, working independently of each other, had excavated and removed, up to March, 1911, an aggregate of 198,000,000 cubic yards of coal and accompanying rock, or 3,000,000 cubic yards more than the total amount of material excavated and to be excavated by the United States in constructing the Panama Canal. This fact illustrates something of the magnitude of the problem that the city of Scranton, with the aid of these engineers and of a special commission or advisory board, has undertaken to solve. The excavation has included 177,000,000 tons of coal and 44,000,000 tons of rock and accompanying refuse. This leaves about 420,000,000 tons of coal still to be removed. As a result of other investigations and of experience in adjacent anthracite mines, Messrs. Conner and Griffith and the advisory board of engineers have advised that, as far as may be necessary to prevent dangerous surface subsidence, the spaces remaining beneath the city of Scranton from the excavation of the above-described material should be filled with sand and other materials by flushing or other processes. This operation is expensive, but it is believed to be not beyond the reach of what is practicable, nor in excess of the value of the coal that may be removed and the amount of damages that may result from the caving in of the surface if such a plan is not carried out. No one realizes so fully as do the authors of this report the need of additional tests and other investigations before the data now pre- sented by them can be fully accepted as sufficient for all purposes in the solution of the problem; and it is expected that at some early date a more extensive series of similar tests can be made by the Bureau of Mines under the supervision of Messrs. Conner and Griffith on a larger scale and under a greater variety of conditions. The field examinations made for the Bureau of Mines by N. H. Darton, which are described briefly in a chapter of this bulletin and will be discussed at length in a bulletin to be published later, indicate the extent and distribution of the sands, gravels, and other materials in the Scranton-Wilkes-Barre district available for flushing purposes if further tests indicate their relative merits; and it is expected that the relative merits of these different materials will soon be tested under such conditions as will furnish the desired information.

Jan 1, 1912

By David L. Moffatt

Considerable current interest is evident[l,2] in the use of transient electromagnetic methods for subsurface remote sensing. A transient method is discussed which uses a periodic video-type pulse containing a wide frequency range. A video pulse is used as an interrogating signal both for "target" identification and detection for relatively short depth (c 20 meters) applications in soil and soft rock media. If the medium is favorable, e.g., hard rock, greater depth applications appear to be feasible. The same procedures would be applicable for deep geological exploration but would require a substantial reduction in frequency and increase in target size. It should be noted that video pulse generators with 35 kv peak voltage and nanoseconds base widths are now within the state-of-the-art, thus significant power over broad spectral ranges is possible. In the design of a video pulse sounding system, 5 main problem areas can be identified; 1 ) selection of the pulse shape or spectral content of the video pulse, 2) design of a radiating structure which effectively couples such a pulse into the medium, 3) isolation of the radiating and receiving mechanisms, 4) realistically accounting for the dispersion and attentuation of the medium and the air-medium interface, and 5) interpretation or processing of the received signal waveform. Each of these problem areas will be discussed and illustrated with experimental and/or theoretical results. The Video Pulse Selection of the proper video pulse signal is dictated by 3 considerations, the maximum desired depth of penetration, the attenuation of the medium and the required resolution and size of the target. For a lossy medium, penetration and resolution are clearly at cross purposes and a compromise is necessary. The exact nature of the compromise is dictated by the application, but the spectrum of the video pulse should not contain any frequencies higher than the predicted cut-off, i.e., that frequency which is attenuated to the threshold level of the receiver. As a practical matter, it may be necessary to select 1 or 2 video pulses reasonably suited

Jan 1, 1973

Four catalytic converters for diesel exhaust systems were tested to determine their effectiveness in reducing the amount of harmful substances discharged into the air. Tests were conducted with four different catalytic converter designs, using two diesel engines as exhaust gas generators. (Of the four noble metal catalytic converters, three are commercially available.) Testing showed that the catalysts varied widely in oxidation efficiency at light to intermediate engine loads, but that all were very effective in reducing emissions of CO, HC, aldehydes, and odor intensity at heavy loads (engine operating modes resulting in high exhaust temperatures). Particulate loading, particulate size, and NOx emissions were generally unaffected by any of the catalysts. The catalysts had one ad-verse effect on exhaust quality--increased sulfate emissions. Because of the potential problem of sulfate emissions, the exclusive use of catalytic reactors for emissions reduction does not appear to be satisfactory. However, when used with a means for subsequent removal of sulfates, a catalyst can function as a key component in an emissions control system for diesel engines operated in underground mines.

Jan 1, 1978

By Paul S. Lewis

The Bureau of Mines hydrogenated coals of different rank that had been irradiated with either x-rays or gamma rays. Lignite, high-volatile A and C bituminous, and low-volatile bituminous coals were exposed to l billion roent¬gens of gamma-ray radiation; specimens of high-volatile A and C bituminous coals from other sources received 6 million roentgens of X-ray radiation. Irradiated and unirradiated control specimens of those coals were hydrogenated in autoclave experiments at (6,000-p.s.i. final pressure and 400° C. with retention times of 15, 30, or 60 minutes depending on the coal rank and catalytic treatment. Comparison of results from irradiated specimens with those from the control experiments showed that the radiation had no beneficial effect on the coal. High-volatile C bituminous coal may have been affected by radiation more than the other coals. One billion roentgens appeared to reduce the amount of coal converted to liquids and gases by about 10 pct., and 6 million roentgens reduced it by about 6 pct. then catalyzed with tin. In all other cases, the conversion of irradiated coal was either reduced by as much as 4 pct. or was essentially the sank as that obtained with unirradiated coal. Irradiation during hydrogenation nay be effective for increasing the reactivity of coal and should be investigated; further work with coals irradiated prier to hydrogenation is not recommended.

Jan 1, 1962

By M. D. Schlesinger

As part of the development of processes for producing synthetic fuels from coal, the Bureau of Mines prepared a special jet fuel in a pilot plant for evaluation by the Air Force. This jet fuel had all the required physical properties, including the important specifications of high heating value and high density. However, the finished fuel did not pass the stability test specified by the Air Force and conducted by the Southwest Research Institute in a high-temperature research coker. The cause for this instability is being investigated because pure compounds of the type identified in this fuel are known to be stable. The tar acid oil used was a 230° to 300° C. fraction of low-temperature tar obtained by carbonization of a West Virginia bituminous coal in the pilot plant of the Consolidation Coal Co. Both the desulfurization at 400° C. and saturation at 300" C. were done in the vapor phase at 2,500 p.s.i.g. After catalytic treatment and distillation the final jet fuel had a boiling range of 194° to 247° C., a net heating value of 18,420 B.t.u./lb. and a specific gravity of 0.8463 60° F./60° F. It also had u pour point below -62° C., and at 0° C. its viscosity was 4.5 cs. The oil was virtually all bicyclic, 41 pct. noncondensed and 56 pct. condensed.

Jan 1, 1961

By Elaine T. Cullen

Safety training materials appropriate for specific underground noncoal operations in the United States are often outdated or nonexistent. The Spokane Research Laboratory (SRL) of the National Institute for Occupational Safety and H ealth has developed several new training tools, including three videos on common underground activities, software that will allow trainers to create a virtual training mine using their own mine map, and toolbox training materials. SRL is working closely with industry in the development of these tools. Teams of safety professionals are involved in the early stages, and actual mines and miners are involved throughout the production phase. This presentation describes the development process and results of SRL’s safety training projects.

By Maria I. De Rosa

Coal mine fires pose a constant danger to the safety of miners and to their livelihood. Underground mine fires pose an added hazard because of the confined environment with remote exits. Enactment of safety regulations [30 CFR2 75 and 771 for under- ground coal mines and surface coal operations has greatly improved the safety of miners. However, mine fires and fire injuries remain serious hazards for all coal mining operations. This report analyzes mine fires and fire injuries for all U.S. coal mining categories (underground coal mines, surface of underground coal mines, surface coal mines, and coal preparation plants) during 1990-1999. Fires involving contractors are also included in the analysis. Similar analyses (for underground coal mines only) by the former U.S. Bureau of Mines (USBM) were reported by McDonald and Pornroy [I9801 and Pornroy and Carigiet [I9951 for 1950-1977 and 1978-1992, respectively. For comparison purposes, data for 1978-1 992 are mentioned in the "Underground Coal Mine Fires" section of this report. Detailed analyses of mobile equipment fires for all underground and surface coal and metal/nonmetal mining categories during 1990-1999 have recently been reported by NIOSH [De Rosa 20041. Risk rate values (fire and injury risk rates) for the 10-year period (1990-1999) and for five successive 2-year periods within the 10-year period are derived. Risk rate values for individual states for the 10-year period are also derived. Other variables by state and time period include employees&apos; working hours, lost workdays, and coal production (underground and surface coal mines only). The number of fire fatalities is reported by time period. Variables such as ignition source, method of detection and suppression, equipment involved, location, and burning material are reported by five 2-year periods only. Furthermore, the number of fire injuries per number of fires causing injuries and total fires has been analyzed by year, ignition source, equipment involved, and location. For comparison purposes, the major fire and fire injury findings for all coal mining categories have been reported. The data in this report were derived from "Injury Experience in Coal Mining" [MSHA 1991a, 1992,1993,1994a, 1995a, 1996, 1997, 1998b, 1999c, 20001, "Fire Accident Reports" [MSHA 199 1 b,c; 1994b; 1995b,c; 1998a,c,d,e,f; 1999a,b,d,e], MSHA "Fire Accident Abstracts" internal publications, and verbal communications with mine personnel. Mining companies are required by 30 CFR 50 to report to MSHA all fires that result in injuries and fires that are not extinguished within 30 min of discovery. A small number of fires lasting <30 min without injuries reported in the "Fire Accident Abstracts" have been included in this report. The analysis in this report will provide the National Institute for Occupational Safety and Health (NIOSH), the Mine Safety and Health Administration (MSHA), and the mining industry with a better understanding of the causes and hazards of mine fires and fire injuries. It will also form a basis for developing future fire research programs.

Jan 1, 2004

By M. B. Cooke, A. D. Bauer, E. W. Dean

The Bureau of Mines is collecting and analyzing representative samples of crude petroleum from all the producing fields in the United States , and the results are being published in a series of reports that are preliminary to the issue of a bulletin covering the entire survey . The bureau has recently completed a survey of crude oils from the Kansas district . In all 27 samples were collected and analyzed , under the direction of A. W. Ambrose , chief petroleum technologist of the Bureau. Valuable assistance was received through the cooperation of oil companies operating in the State , especially the Prairie Pipe Line Co. , and the Empire Pipe Line Co. The present report issued as Serial 2322 , on the Kansas crudes , forms the fifth of the series . Of the four previous papers , the first ( No. 2202 ) deals with crudes from the Eastern fields of the United States , the second ( No. 2235 ) with crudes from the Rocky Mountain district , the third ( No. 2290) gives additional data , cn viscosities and pour tests , for the crudes from these two fields , and the fourth ( No. 2293 ) covers the fields of northern Texas , northern Louisiana , and Arkansas . The details of the methods of collecting samples , making laboratory tests and interpreting results , have been discussed in these earlier reports . It has also been pointed out that the only adequate method of interpreting analyses of crude oils is to compare the individual reports with the analysis of some crude oil that is familiar to the operator . For this reason , no comprehensive discussion of the results of the Kansas survey is attempted, although some general statements may be made .

Feb 1, 1922