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By D. Noon

Mine production crews and drill-and-blast crews may be exposed to unexpected movement of ground when working under pit slopes. Without specialist geotechnical advice and appropriate measurement systems, mine crews are faced with conducting risk assessments and relying on subsequent controls that may or may not be adequate to ensure their safety. Mine crews need an ?early warning? monitoring system to give them the confidence that they will have time to walk out of the danger zone if the pit slope begins to move. Slope stability radar technology is used by mine geotechnical engineers to assess overall slope stability over an extended period, typically days or weeks, and to critically monitor slopes that are actively moving and may become unsafe. The complexity of slope stability radar allows for geotechnical engineers to assess movement types and movement rates across multiple work areas of a mine from long ranges, with alarm capability to a central location. However there are many mine work areas where production and drill-and blast crews are not adequately covered or alarmed by slope stability radar systems. What is required is an easy-to-use, short-range, fast-scanning tool that can be operated directly by a work crew and can provide a local alarm with sufficient warning when a wall movement occurs within the work area. The Work Area Monitor (WAM) concept has been developed specifically to be operated by a mine production crew. The system comprises a sensitive, fast-scanning radar coupled with a high-resolution camera, built into a mine-standard light vehicle. The system has been designed specifically for ease of use with the output being a local area alarm to warn workers of slope movement in their vicinity, as opposed to the broader pit monitoring and long-term deformation measurements of the known slope stability radar systems.

Jan 1, 2012

By James D. Bittner

Separation Technologies, LLC (ST) has developed a processing system based on triboelectric charging and electrostatic separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. The environmentally friendly process can eliminate wet processing and required drying of the final material. The process requires little if any pre-treatment of the material other than grinding and operates at high capacity ? up to 45 tonnes per hour by a compact machine. Energy consumption is low, approximately 1 kWh/tonnes of material processed. Since the only potential emission of the process is dust, permitting is typically relatively easy. In contrast to the other available electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the ST belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (500 µm) materials with very high throughputs. The triboelectric particle charging is effective for a wide range of materials and only requires particle ? particle contact. The small gap, high electric field, counter current flow, vigorous particle-particle agitation and self-cleaning action of the belt on the electrodes are the critical features of the ST separator. The high efficiency multi-stage separation through charging / recharging and internal recycle results in far superior separations and is effective on fine materials that cannot be separated at all by the conventional electrostatic techniques. Since 1995, this triboelectric process has been extensively used for the beneficiation of coal fly ash with eighteen separators in place and over 100 machine-years of operation at locations in the US and Europe. The technology has been also successfully applied to the beneficiation of a variety of minerals including calcium carbonates, talc, and potash.

Nov 1, 2011

By A. G. Rozner

TRANSVERSE rupture tests have been commonly used in mechanical investigations of brittle materials. The specimens are simple, easy to prepare, and loading presents no difficulty. Owing to the complexity of stress distribution in bending1 one can determine stresses rigorously only for the elastic range. The bend-test results, however, are at times converted into tensile-strength data, determined as maximum fiber stress. The assumption is made that for small plastic deformations the linear stress-strain relation applies. This problem was experimentally investigated by Bach3 who tested cast iron in bending and in tension and found that the maximum fiber strength obtained in bending exceeded the experimental tensile strength by a factor depending on the geometry of the tested piece. The factor varied from 1.57 for a rectangular cross section to 2.12 for a circular cross section of the tested beam. Since this work was carried out 60 years ago, the cast iron used could be expected to have been highly brittle, thus the extent of plastic deformation prior to fracture very small. We have therefore carried out a number of tests on magnesium-modified cast iron with an average elongation of -5 pct. It was hoped that the data obtained from the tests would serve as a guideline for comparing data obtained in tension and bending for brittle materials. Mechanical properties were measured at room temperature on an Instron tensile machine at a crosshead speed of 0.05 in. per min. The three-point bend test employed cylindrical bars 0.20 in. in diameter with a 1.0-in. span. For the tensile test, cylindrical tensile specimens with a gage length of 0.85 in. and a diameter of 0.160 in. were used. Results are summarized in Table I. From Table I one can see that fracture strength

Jan 1, 1965

Under the sponsorship of the U.S. Department of Energy, a project was completed in 2005, which studied the use of a special pneumatic capsule pipeline (PCP) system, driven by linear induction motor (LIM), for transporting minerals and/or mine wastes. In this study, the pipeline is a rectangular tube of 1m × 1m cross section. The capsules are similar to railroad cars running on small rails imbedded in the tube. A LIM is placed AT the entrance of the tube to transfer power electro-magnetically from the LIM to capsules. The capsules going through the LIM, propelled by the electromagnetic field generated by the LIM, move faster than the air and hence impart energy into the airflow. This in turn pushes the capsules in the tube forward. When the tube is long (say longer than 10 km), additional LIMs may be needed along the tube to serve as booster pumps. An advantage of using LIMs instead of blowers as used in ordinary PCPs is that capsules can pass through the LIMs unhindered. This enables the use of booster pumps for long tubes. It also enables PCP to achieve much higher cargo throughput than that of PCPs using blowers, thereby reducing unit cost ($ per ton-km). Advantages of using capsules with steel wheels running on steel rails in the tubes including: (1) contact friction is only about one-fifth of that using rubber tires, thereby conserving energy, (2) capsules can run at a much higher speed than those using rubber tires without overheating and damaging the tires, and (3) rails make capsule motion control simple; they restrict lateral movement of capsules, and make branching easy-by using standard rail crossing equipment. This advanced PCP system combines the advantages of LIM with the advantages of rails, resulting in a super-efficient tube system having throughputs an order of magnitude greater than that of conventional PCPs, and having an energy efficiency better than railroad transport. Analysis shows that the system is highly cost-effective when throughput is high-at least 5 million tons per year. The system is most suitable for long-distance transportation of minerals (including coal and flyash) and wastes (including both mine wastes and municipal solid waste).

Jan 1, 2014

By Jack Parker

Critical width Before we go further into pillar design, we should look into the matter of "critical width," because of its effect on pillar behavior. Critical width refers to the greatest width that the rocks above the mine can span before failure or, if there are pillars, the width to which we must mine before the pillars accept the full weight of the overlying materials. There are theories to help calculate that probable width, and they usually boil down to one-quarter or one-third of the depth of cover; but they don&apos;t always fit, and it would be better for us to understand the factors that control local conditions. Critical width may be controlled by the thickness or strength of one or more of the strata above the mining horizon. In a gold mine, we might have a thick granite or basalt above us, perhaps capable of bridging across most or even all of a small ore body. In that case, pillars might have to support nothing, or perhaps just the weaker or damaged rock below the strong main roof. Obviously it would be wrong to design for tributary load on pillars based on some lab-determined rock strength. In some coal mining districts in Utah, huge steps can be seen in the mountain sides, with slopes on weathered shales and vertical cliffs 100 or 200 ft high in thick, hard sandstones. The sandstones are capable of bridging across hundreds of feet, often making mining deceptively easy at first, but it becomes more difficult as greater areas are opened. Sometimes such a mining sequence leads to violent bumps and bursts as the wide spans of sandstone sag and bear down on the working faces, like giant nutcrackers, or as bridges eventually fail, releasing much pent-up energy.

Jan 1, 1993

By Peter Yen

This session consists of five papers. Three involved research on the properties of grout materials, specifically ultrafine cements and polyurethane grouts. Two papers present the development of soil grouting technology and monitoring methods. Of great interest are the papers on ultrafine grout penetrability testing focusing on the pressure filtration effects encountered in permeation grouting applications (Ericksson, Stille and Mittag, Savidis). The comparison testing of hydrophilic and hydrophobic polyurethane grouts submitted by Vrignaud, Ballivy, Perret and Fernagu assessed the long-term performance of these materials for repairing saturated cracks in concrete, subject to thermal expansion and contraction. Two very practical papers present the development of soil grouting, where permeation, fracture, replacement, jetting and other grouting techniques are utilized. The papers by Lees with Chuaqui and Warner present experience with ultrafine and other commonly used grout materials. Methods to measure and monitor the injection process and verify production progress are discussed.

Feb 10, 2003

By John H. Soule

"Although known since 1902, the Capitan iron deposits have not been mined, mainly because of the low grade of the ore. Only a small amount of exploratory work has been done since the discovery. C. H. Johnson, district engineer of the Bureau of Mines in New Mexico in 1942-45, visited the property; as a result, preliminary sampling of the property was done in 1943.3/ Owing to the results of this preliminary work, an extensive development program by wagon drilling was planned and executed early in 1944.4/ Equipment available at that time was limited in the depths that could be reached; and, as geologic studies indicated the possibility that other limestone beds below the surface might have been replaced by iron minerals, a supplementary development program by churn drilling to reach greater depths was prosecuted in late 1947 and early 1948, with the author as project engineer.The following sections note the location and accessibility of the deposits and mention the physical features, climate, labor and living conditions. Property and ownership are outlined, the history and production of the property stated briefly, and the ore deposits are described. The work done by the Bureau of Mines is explained and supported with maps, sections, and assay logs.From March 1, 1944, to June 1, 1944, 179 wagon-drill holes totaling 3,490 feet and 4 test pits totaling 75 feet were completed, and from November 1947 to February 1948 seven churn-drill holes totaling 2,488 feet were drilled and sampled. Metallurgical tests are summarized and referenced.With respect to this report, special acknowledgment is due to J. H. Hedges, chief, Tuscon, Ariz., Branch, Mining Division, and to W. R. Storms, engineer in-charge of the Silver City, N. Mex., field office. Acknowledgment also is due to J. Bruce Clemmer, chief, Tuscon Branch, Metallurgical Division, for analyses done in the last phase of this project, and to Dr. Vincent Kelley of the Federal Geological Survey for his cooperation during this work.The Capitan iron deposits are in secs. 10, 11, 13, 14, and 15, T. 8 S., R. 14 E., central Lincoln County, N. Mex., as shown on figures 1 and 2. The only known large deposit upon which the Bureau did development work lies around the common corner of secs. 10, 11, 14, and 15, as shown in figures 2 and 3, and just southwest of and in the foothills of the Capitan Mountains. This range of mountains trends east and west. The elevation of the highest peak is 10,205 feet.The deposits are reached by traveling on State Highway 48 from Capitan north for 4 miles, to a point just inside the Lincoln National Forest fence and thence due east over a poor dirt road for 1.2 miles. Just over a small wooden bridge, the left-fork is taken, and the poor road is followed to the deposits, a further distance of 1.1 miles (see fig. 1). This road follows the fence to and through the Davis ranch. All the roads from Capitan to the deposits are dirt roads but are impassable only for short periods during and after heavy rain or snow."

Aug 1, 1949

By F. Arslan

Gold extraction from refractory ores is still a problem. Gold losses in the cyanidation process are mainly due to the presence of sulfides and carbonaceous materials. Oxidation of carbon and sulfide minerals by sodium hypochlorite is a possible method to render the ore amenable to cyanidation, and earlier work by the USBM indicates that electrochemical generation of hypochlorite is promising. Laboratory work was carried out on the oxidation of pyrite and carbon in an electrochemical cell with a sodium chloride electrolyte. The results of preliminary tests are discussed in relation to the mechanism of electrooxidation of refractory gold ores and the estimation of current efficiency.

Jan 1, 1991

By A. L. Engel

In the period of 1942-1945, medium-grade, oxidized, lead-silver ore was mined and shipped from the Diamond district near Eureka, Nev. An encouraging tonnage of low-grade ore was developed during these operations and partly blocked-out for future mining. If the low-grade ore could be treated profitably, further development of the district would result, and production of an important strategic metal might be increased. A representative sample of Diamond district ore was obtained through the Reno office of the Mining Division for the studies described in this report. The sample consisted of lumps and fines of a highly altered siliceous rock containing much earthy red hematite and some granular black hematite. Examination with the binocular microscope showed the lead carbonate mineral, cerussite, in seams and disseminated in the hematite. No zinc or silver minerals were identified, and no sulfide minerals were present. Analyses of the ore showed:

Jan 1, 1951

By J. F. Wright

Introduction Previous to 1924 the mining fields of Manitoba and adjoining territory had not been prospected in detail, and the reports of the exploration of the mineral discoveries to that date had been discouraging. As a result of the apparent failure of all the mining operations, some considered that geological conditions in the country westward from lake Superior extending across western Ontario, eastern and northern Manitoba, and northern Saskatchewan, were different from those in the northeastern part of Ontario, where large gold mines had been developed. Discoveries of importance thus were necessary to renew interest in the mining possibilities of this part of the Canadian Shield, and the successful operations at Flin Flon and Howey in large part were responsible for the beginning of the present activity in what may be described as the part of the pre-Cambrian Shield within central Canada. In Manitoba, the more important developments at present are in the Central Manitoba, Gods Lake, and Knee Lake fields. The large area from west of Flin Flon east to Herb Lake, also, is being explored carefully for gold deposits of merit. A number of properties in Red Lake, Woman Lake, and Pickle Crow areas are being drilled and explored underground. Many of the mines of the Lake of the Woods area, that were producing gold 30 years ago, are re-opened, and new prospects in this field and in the country to the east are being explored. The recent development of Little Long Lac mine in an area near the railway, and considered by some to have been thoroughly prospected years ago, has stimulated interest in the areas formerly prospected. In the autumn of 1934, the belts of greenstone and sediments in the country east of lake Nipigon were staked, and deposits in these fields will be explored in detail this year. This paper is presented to discuss the general features of the geology and gold deposits of the various prospecting fields in Manitoba and adjoining territory. Details of a number of the areas and mines will be presented at this meeting in papers by Barton on Little Long Lac, Tanton on Sturgeon River, Baker on Gods Lake, and Brownell and Kinkel on Flin Flon. Although mining was not active in most of this territory previous to 1930, geologists of the various government departments continued field studies and interesting reports were issued.

Jan 1, 1935

By P. Pal Roy, R. B. Singh

"This paper focuses on a number of interesting results to establish the theory and principle of air-deck blasting. It also gives the mechanism of breakage that takes place in air-deck blasting under varying charge load conditions. With these aspects in mind, the mine management can implement this up-coming technology to enhance safety and higher productivity. IntroductionThe method of air-decking has become an increasingly popular technique in production and presplit blasting. In the blasthole, an explosive column is combined with an airchamber. The main aim of the technique is to control breakage through effective distribution of explosive energy and thereby enhance uniform rock fragmentation. An air column lowers the initial pressure of the explosive products and simultaneously increases the time of interaction for the detonation front with the surrounding rock, which enhances rock breakage.To study air-deck blasting, CMRI initially conducted experiments using indigenously developed, low-cost wooden spacers of different sizes and strengths. Air-deck blasting was first tried using these spacers in 1993 at Jambad OCP, ECL and Chasnalla OCP, IISCO. The experiments were extended in 1994 at Bermo Mine, DVC. The results were subsequently published by Pal Roy et al., in 1995. It is worth mentioning that the performance of air-deck blasting during this period was only compared with conventional blasting practices without going into detail of the theory behind the process."

Jan 1, 2001

By William R. Kohl, Craig B. Clemmens

"Since 2010, North Central Resources, Bridgeport, WV, has been using the sonic log to estimate the rockmechanics properties of the coal and adjacent strata in their exploration drilling program. In 68 out of the 85 boreholes they have drilled since 2010, they have conducted shear wave analysis on sonic logs run in these boreholes. By incorporating the rock mechanics logs into the geological model of the coal seam, the engineers can develop a better understanding of the support requirements for the mine.WellCAD Borehole processing software provides vastly improved efficiency in analyzing shear waves from borehole sonic data than previously available methods. The calculation of most rock mechanics parameters requires knowledge of the density and both the compressional wave velocity and the shear wave velocity. Density logs are well known and an industry standard. Sonic logging is equally well known, although less frequently used, as an accurate source of compressional wave velocity. Shear wave velocity is difficult to measure in a geophysical log, but can be estimated from digitally recorded wave form records. This is a time consuming manual procedure which requires the visual examination of thousands of individual wave forms.WellCAD allows the viewing all the wave forms on a VDL display. The observer can create a pair of false logs by manually tracing the interference points on the display for each receiver. He can check himself by observing wave forms in the traditional format. He can then create a shear wave transit time log or “Delta-S” log by subtracting the false log from the near receiver from that of the far receiver. This can be plugged into standard formulae to generate curves for most standard rock mechanic parameters, including bulk modulus, shear modulus, Young’s modulus, and Poisson’s ratio.While these parameters do not entirely substitute for destructive testing, they are extremely cost effective. An entire borehole can be analyzed for the cost of a single destructive test. This allows for a more judicious use of destructive testing while permitting the extension of test data into the rock mass with much greater confidence."

Jan 1, 2015

By James P. Kimball

Jan 1, 1881

By Mu Chen, Ye-Shuang Xu, Dong-Wei Hou, Shui-Long Shen, Huai-Na Wu

"This paper presents a laboratory investigation on the mechanical behaviors of the cement-clay admixture improved by polypropylene fiber. Cement can significantly improve the clay admixture. The fiber additive also improves the strength and ductility of the improved clay. The Unconfined Compression Strength (UCS) of the polypropylene fiber-reinforced cement-clay presents an overall trend to grow with the increase of fiber length. The improved clay reached its peak strength at the fiber content of 0.5%. Then the UCS of the improved clay will slowly reverse if the fiber content continues to rise. For study of curing time, improved clay behaves better in its early strength, but an inhibition will be brought about if fibers are excessive.INTRODUCTIONGround improvement technology is essential for construction of structures in soft ground. Some traditional techniques often cost much but result in little. For instance, along the coastal region of China, soft ground is often improved by backfill with high quality sandy soil transported far away, leading to high additional haulage costs and long construction period. Reutilizing the excavated soil as backfill or subgrade after treatment, by contrast, will be more economical and effective (Hufenus et al., 2006). Many researches have been conducted to improve the compression strength of soft soil, among which, the method of mixing the soft soil with cement and fly ash is one of the most common ways (Kolias et al., 2005; Horpibulsuk et al., 2009; Porcino et al., 2012). It is known that soil resists well against compression and shear force but behaves poorly in resistance to tension. Therefore, utilizing tensile elements such as fibers and strips to improve the tensile strength will be effective because of its strength isotropy, better durability and cost effective (Haeri et al., 2000; Kaniraj and Havanagi, 2001; Consoli et al., 2010)."

Jan 1, 2015

By James R. Craig

The General Image Processing System (GIPSY) is being employed for the quantitative textural analysis of complex sulfide ores from the Southern and Central Appalachians and for the determination of liberation characteristics of the mineral constituents during grinding. Optical images from a microscope-mounted TV camera or from 35mm film are converted into digital images which are subsequently analyzed by GIPSY, a transportable image processing software package. Properties measured by GIPSY include spatial distribution of mineral constituents, grain sizes, grain shapes, grain orientation and mineral co-occurrences.

Jan 1, 1982

By O. N. Mohanty, S. Mohan Rao, N. D. Rao, T. Mukherjee, P. V. T. Rao

"Tata Steel has its captive chromite resources at Sukinda, Orissa. They contain two ore types, i.e. (i) Ferruginous and (ii) Siliceous. The generation of off-grade ores is an increasing trend and simultaneously customer quality requirements are becoming ever more stringent. The ferruginous type ore also contains a considerable quantity of in-situ fines (~20% particles below 0.5 mm) that compound the beneficiation problem.In this paper, new strategies are discussed for producing additional value.added products after evaluating the present beneficiation practice in terms of changing market scenario, processing capability of the plant and ore characteristic. They would entail use of MGS - an enhanced gravity separator, for recovering additional products from plant tailings; production of ferruginous coarse concentrates (-3+0.5 mm with ~46% Cr2O3) using jigs; production of marketable grade lumpy (-40+10 mm size) concentrates from low grade siliceous ore using jigs and >2.8 Cr/Fe ratio siliceous ore fines treated in the Chrome Ore Beneficiation plant gravity circuit units and low intensity magnetic separator. The studies indicate that it is possible to recover 79-80% of the chromite, against a theoretical maximum of 82% from both the ore types, in the form of several marketable grade concentrates that would also include refractory grade."

Jan 1, 2003

By Wei Wang

The SMCO copper plant is located in DR Congo, and was designed by China NERIN Engineering Co., Ltd. The process is a typical hydrometallurgical plant with Leach-SX-EW, with the project treating the oxide minerals with agitation leaching, followed with three stage of solvent extraction and two stages of stripping, and using permanent SS cathodes to produce LME grade copper. Because of the special characteristic of the ore, what contains 2 different type of oxides (one high carbonate oxide and the other low carbonate), there are several new technical measures that have been developed and adopted for the plant. For example, different grinding, leaching, and filtering are used to treat different oxides. This paper, presents the project process, engineering design, construction and commissioning. The paper also describes some of the problems encountered during plant commissioning, such as the agitation leaching tank issues, and corrosion in the settler-mixer. This paper discusses some NERIN solutions to these problems, and explains the use of the CN filter, which is used to filter PLS to treat high level suspend solids, instead of the traditional sand filter. Finally, this paper also proposes steps / measures for further improvement for future plant operation.

Jan 1, 2014

By A. Bauer

This paper describes the trends in recent years in explosives formulated to produce larger blast-hole spacings and over-all lower drilling and blasting costs in hard formations. A consideration of current rotary drilling costs per ft of hole and per ton of muck versus hole diameter indicates that it is now possible that we shall see much further use of lower-energy-content, lower-cost slurries and dry mixes, and larger-diameter and, in many instances, cheaper blast holes. These will be drilled on current or slightly larger blast patterns to yield the same energy input per ton of rock and similar fragmentation at lower costs.

Jan 1, 1968

By C McHugh, F Oppolzer, B Rogers, A Stokes

Rio Tinto has embarked on a journey to use automation to improve the performance of its surface mines. The driver for automation has more to do with improving the accuracy and consistency of mining processes and less to do with cost savings through labour reduction.A key task in most surface mines is blasthole drilling. The degree to how well this is done cascades through the downstream mining process. It impacts scheduling, excavation, slope stability, material handling, beneficiation, ore loss and final product blending. Improved blasthole drilling was identified as an objective that has a significant business case in most of Rio TintoÆs surface mines.This paper describes Rio TintoÆs multi-drill automation project, which has developed a robust system for automating most of the functions on several Caterpillar SKSS16 drill rigs. Automated drilling is currently being trialled in production at the West Angelas iron ore mine in the Pilbara region of Western Australia. A description of the essential elements of the automated multi-drill system is given together with an overview of how automated drilling is performed remotely from the operating bench.A review of the performance and benefits of the automated multi-drill system is given together with future plans to extend the functionality of automated drills.CITATION:McHugh, C, Stokes, A, Oppolzer, F and Rogers, B, 2012. Automated multi-drills in Rio Tinto, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 83-88 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By M. U. Khan

"Underground mine diesel equipment generally offers more flexibility as compared to electric powered systems. Diesel exhaust is an adverse agent which affects the health of underground miners. The National Institute of Occupational Safety and Health (NIOSH) regard diesel exhaust as carcinogenic. The NIOSH 5040 method is an established technique for measuring Diesel Particulate Matter (DPM). This process inherently involve a lag time before an accurate exposure determination can be made during which miners are potentially overexposed to DPM. This issue can be addressed by using realtime DPM monitors. This paper presents underground mine shift average based and realtime monitored DPM values monitored in US mines. A FLIR Airtec instrument has been used for realtime measurement whereas shift average based DPM has been determined by the use of NIOSH 5040 method. A log of diesel equipment movement was kept. DPM concentrations versus time were plotted and analyzed. High DPM sources were identified and the FLIR Airtec was demonstrated to be satisfactory for realtime DPM measurements. INTRODUCTION The use of diesel equipment in mines is an attractive option due to its ability to convert a large fraction of available energy into useable work. Diesel engines are rugged, dependable and fuel efficient. It is very common for diesel engines in heavy duty trucks to have a life of 1,600,000 km [Anon, 1999]. Generally in underground mines compared to electric powered equipment, diesel equipment provides more maneuverability. It can be assumed that the underground mining industry will maintain its reliance on diesel powered equipment keeping in mind the recent developments in other energy alternatives [Anon, 2001a]. A harmful aspect to the use of diesel as a fuel is its resultant emission as an adverse environmental exposure agent. Generally diesel particles are approximately one order of magnitude smaller than respirable dust aerosols in underground mines (typically less than one micron in size) [Kittelson, 1998]. Force of gravity has less effect on DPM due to its small particle size. The phenomenon of less gravitational attraction increases the settling and residence time of DPM in the mine atmosphere. High residence time of DPM as compared to other mechanically generated particles increases the chances of diesel particles deposition in the human respiratory tract. The small sized diesel aerosols penetrate deeply into regions of the human lung [Morawska. et al. 2005], which increase the health risks associated with long term exposure to diesel aerosols. Published studies documented the adverse health effects of DPM exposure [Walsh M.P., 1999]. Continuous and long term DPM exposure can result in respiratory disease, lung cancer, reduced lung capacity, and heart disease. NIOSH has declared that the reductions in DPM exposure would reduce cancer risks. In underground mines DPM determination is a challenging task and it is becoming a matter of serious concern due to the harmful health effects associated with the exposure of DPM. The current study involves the determination of realtime and shift averaged based DPM in underground mines of United States of America (USA). Realtime DPM was measured using FLIR Airtec monitors and shift averaged based measurement was performed by the MSHA approved NIOSH 5040 method. FLIR Airtec uses laser scattering approach to measures the Elemental Carbon (EC) component of the DPM. The results from the FLIR Airtec were compared with the results of NIOSH 5040 method and its performance was found satisfactory."

Jan 1, 2015