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By W. C. Elli, M. E. Fine

YOUNG'S modulus of elasticity in metals ordinarily decreases with rising temperature. The range of the thermoelastic coefficient at room tem- 1/E dE/dT perature (temperature coefficient of modulus, is illustrated1 by the values for tungsten and hard-drawn aluminum, —95 and —1220x10-6 eg C-1. However, a nearly zero thermoelastic coefficient is observed in some ferromagnetic alloys over a limited temperature range. In these alloys, as the temperature is raised, an increase in modulus arising from loss of ferromagnetism compensates the normal decrease. Iron-nickel alloys containing 36 to 52 pct Ni behave in this manner. In the present investiga- tion, the dependence of the modulus and thermo-elastic coefficient on cold working and annealing were studied in iron-nickel alloys in this range of nickel. Although these alloys, when fully annealed, have a coefficient near zero over a very small temperature interval, the temperature range of low coefficient can be extended greatly by straining and then stress-relief annealing. The modulus of face-centered cubic iron-nickel alloys annealed at 1000°C does not vary linearly with composition at room temperature but, as shown by the solid line of fig. 1, from Koster,' is minimum at 40 pct Ni and maximum at 87 pct Ni. The modulus increases with applied magnetic field but retains the minimum near 40 pct Ni. Schematic change of modulus with temperature for three compositions is shown in fig. 2.'. ' With increasing temperature, the slope becomes less negative, goes through zero (temperature of minimum modulus for the alloy), becomes positive, and resumes its normal negative value above the Curie

Jan 1, 1951

By Joel Ochoa, Miguel A. Montiel

El artículo da cuenta del estudio de un prototipo de placa de desgaste para chutes de transferencia con un nuevo sistema de sujeción. El sistema fue validado mediante el software Ansys. La innovación no solo está constituida por un nuevo diseño sino también por el tipo de proceso productivo para la fabricación del producto mejorado. Se incluyeron ensayos con torquímetro, que presentaron resultados favorables.

Sep 30, 2019

By Afshin Sadri, Wai Lai Ying, Brycklin Wilson, Zoe Coull

"Although there have been great steps forward to integrate corrosion engineering into operations, there is still an underlying tendency for maintenance tasks to be performed in a reactive manner. This is especially true when strategies focus on lagging indicators such as visual inspections, RCA (root-cause analysis), and FMECA (failure mode, effects and criticality analysis). This trend to “reactive maintenance” can be avoided by utilizing more inspection and monitoring methods to identify leading indicators of failures. Prevention is generally less costly than repairs; moreover, when paired with appropriate monitoring techniques, intervention of corrosion protection can be more effectively timed and based on more accurate data. Hatch asset reliability studies show nearly 80% of defects are introduced through operations and maintenance. Therefore, proactive corrosion management can provide the necessary feedback to optimize operations and maintenance strategies preventing costly corrosion losses. Understanding corrosion risks gives a clear picture of the benefits of a proactive approach to asset performance. Monitoring techniques (Non-Destructive Testing, field testing, sampling, etc.) by nature are a more effective means of improving maintenance efforts and preventing corrosion losses than other methods (RCA, FMECA). This paper will outline the importance of proactive corrosion management and demonstrate its benefits through industry examples.INTRODUCTION Over the past few decades, with the growth of technology and awareness of sustainable development many studies have shown the benefits of a proactive approach to maintenance strategies. However, in practice there is still an underlying tendency for maintenance tasks to be performed in a “reactive manner”. This is especially true when strategies focus on lagging indicators such as visual inspections, RCA (root-cause analysis), and FMECA (failure mode, effects and criticality analysis). This trend to “reactive maintenance” can be avoided by utilizing more inspection and monitoring methods to identify defects and leading indicators to failures."

Jan 1, 2017

By John C. Gagliardi

The size and complexity of modern surface haulage trucks has resulted in an increased reliance upon sensors and electronic-based instrumentation for safe and efficient operation. Design engineers need accurate information about the equipment vibration environment to efficiently and effectively build components for installation on mobile mining equipment capable of withstanding the mine environment. Examples of such components include backup alarms, communication equipment, microprocessor-based controllers, and a wide variety of sensors. Unfortunately, this information is not available to the majority of both original equipment and aftermarket equipment manufacturers. To address this problem, the U.S. Bureau of Mines performed field vibration measurements on a variety of surface mining haulage trucks. The vibration measurements were then analyzed and test specifications were developed in the form of envelopes. In conjunction with test specifications, recommendations to aid manufacturers in implementing a vibration environment test program have been included with an illustrative example.

Jan 1, 2010

By Jean Igor Margem

Nestes dias materiais ecológicos como compósitos com fibras naturais em matriz polimérica estão chamando a atenção de pesquisadores científicos, devido ao seu bom desempenho na substituição de materiais como madeira, polímeros à base de petróleo e outros. Neste trabalho foram avaliadas as propriedades de tração de compósitos de matriz poliéster reforçados com diferentes espécimes de fibras lignocelulósicas. Compósitos reforçados com até 30% em volume de fibras longas, contínuas e alinhadas de malva, sisal e bambu foram testados em uma máquina Instron a temperatura ambiente. A fratura foi analisada por SEM. Os resultados mostraram alterações significativas nas propriedades mecânicas com a quantidade dessas fibras. Estas propriedades mecânicas foram comparados com outros resultados em compósitos testados em ensaio de tração. Como esperado, a análise da fratura revelou uma fraca interação da interface fibra / matriz, o que corrobora o comportamento típico das fibras naturais quando incorporadas em matriz polimérica.

Oct 30, 2017

By P. Scinto, P. Hudson

"Modern day ore bodies are becoming increasingly harder, more abrasive and lower grade. The Mako deposit is located in Senegal and consists predominantly of primary mafic and felsic lithology that are both very competent and very abrasive ores (Axb < 30, BWi >20 and Ai >1.0). The deposit was initially discovery in 2010 and the Toro Gold management team fast tracked the Mako Project through development and into production to achieve its first gold pour in January 2018. The comminution circuit comprises primary crushing single stage SAG milling with recycle crusher (1oCR SS-SAC). The mill reached design throughput and grind size seven weeks after first ore. The Mako project marks another successful international application of single stage milling, which represents a simple and easy to operate comminution circuit for small-to-mid size projects with a low capital cost. This paper describes the ore interpretation, comminution modelling, grinding circuit selection and design, as well as an overview of the commissioning and ramp-up of the mill.INTRODUCTION The Mako Gold Project is operated by Toro Gold Ltd., which holds a 90% interest in the project. The project is located in south-eastern Senegal in the Kedougou region, close to the Gambia river and township of Mako. The Mako deposit lies in the “Kenieba Window” of eastern Senegal and western Mali, which hosts a number of gold mining operations and development projects. The Mako Gold Project has an estimated life of 8 years with overall recoverable gold estimated at 924 koz. The process plant is designed to treat 1.8Mt/a of ore and produce 128 – 143 koz of gold per annum. Lycopodium Minerals Pty Ltd (Lycopodium) was appointed to provide feasibility studies and EPCM services for the greenfield project. Forming part of consultancy services provided by Lycopodium, Orway Mineral Consultants (OMC), a subsidiary of Lycopodium, was involved in the design, commissioning, ramp up and ongoing post commissioning support of the comminution circuit."

Jan 1, 2019

By W. Krieglstein

Due to the natural variability of ores, it is necessary to carefully test flotation behavior of flotation cells before designing flotation circuits. For performing quick and versatile tests in the laboratory, Siemens developed a laboratory-size Hybrid Flotation Cell, which has been down-scaled from the 300 m³/h production cell to a 0.6 m³/h flotation cell. This small cell is being used as a test bed for technical and chemical concepts, the improvement of decisive components and the characterization of customer ores. In this study the evaluation results for Andean porphyry copper ores are shown. Total recovery rates of the order of 45 to 50 % have routinely been achieved in a single flotation cycle over a wide range of feed grades. In addition, the Hybrid Flotation Cell has proven to be particularly well suited for the flotation of fine particles below 20 µm down to below 1 µm, at high recovery rates and concentrate grades.

Sep 1, 2012

By S Mitra, B J. Monaghan, T Honeyands, G Evans, R Chowdhury, D Scimone

Due to the harsh operating conditions, wearing of the inner refractory lining in a Basic Oxygen Steelmaking (BOS) furnace reduces the useful life of the refractories and incurs a significant cost component for relining. In this study, firstly, a combined compressible and incompressible computational fluid dynamics (CFD) model was developed to identify the potential wear prone zones in an industrial scale BOS system during the supersonic oxygen blowing phase by quantifying the wall shear stress distributions. Next, the retained slag splashing process was simulated by introducing an inert gas to residual slag mass to achieve a protective coating on the refractory walls. Effect of both design and operational parameters such as lance head configuration, lance position and the initial slag volume on the slag wall coating performance were quantified and most favourable conditions were determined.

Jun 19, 2024

By Robert M. Strong

The following report is a summary of the commercial results which 'Were obtained from 2,000 tests conducted by the technologic branch of the United States Geological Survey at St. Louis, Mo., and Norfolk, Va., in 1907 and 1908, under the technical supervision of R. H. Fernald, engineer in charge of the producer-gas section. The tests dealt primarily with gasoline, forming part of the investigation of mineral fuels provided for by acts of Congress. To determine the relative economy and efficiency of gasoline it was compared with denatured alcohol. The tests, many of which were undertaken in connection with work for the Navy Department, supplemented, to a certain extent, the work of previous investigations, but only so far as was necessary to emphasize some of the more important points and to lead up to the defining of conditions required for the economical use of gasoline and alcohol. In order to determine and eliminate the affecting engine conditions as far as possible, the investigation was commenced by making comparative gasoline and alcohol tests on the same engines. These tests were repeated on other engines of approxiElately the same size and speed, having different degrees of comFression, different methods of governing, and different carburetors. The final report will include much material that may be of use in engine design, but that side of the investigation was not pursued any further than was necessary to obtain the best possible results, for alcohol and for gasoline with the engines at hand, and to prove that the minimum fu·el-consumption rate for each could be obtained in approximately the same manner. The effects of engine and of operating conditions both have a bearing on the commercial deductions but will be discussed only in a general way at this time.

Jan 1, 1911

By Marcel Vallee, Fernand Dubuc

"The St-Honoré carbonatite complex, located 8 miles north of Chicoutimi, Quebec, was discovered in September 1967 as abnormal radioactivity was detected in the course of SOQUEM's aerial surveys. The complex, covered by a shallow layer of Trenton limestone, has been explored by aeromagnetic, ground gravimetric and magnetic surveys, and 12,013 feet of diamond drilling. Its age, from potassium-argon dating, is 650 million years. The carbonatite is approximately kidney-shaped and has a surface area of 6 square miles, 20 per cent of which is explored. It shows a central core of coarse-grained massive dolomitic carbonatite and an outer ring of foliated dolomitic carbonatite.The exploration work to date has resulted in the discovery, in the foliated carbonatite, of an incompletely drilled niobium (columbium) zone of pyrochlore-bearing carbonatite, at least 1,000 by 800 feet in size. This zone contains 5,000 tons per vertical foot grading 0.86 per cent Nb205 or at least 15,000 tons per vertical foot grading 0.66 per cent Nb205 or 45,000 tons grading 0.48 per cent Nb20s. The pyrochlore contains an average of 64 per cent Nb,Os. The central core contains a zone of rare-earth-bearing carbonatite (as monazite), grading up to 4.5 per cent rare-earth oxide, 3,500 ppm zinc and 290 ppm molybdenum. Stocks of nepheline syenite and magnetite diorite accompany the carbonatite. The total analysis and trace-element contents of typical rocks are presented."

Jan 1, 1970

By R. L. Bailey

"The Acheson D-3 Pool was discovered in August 1950, and contains 88 producing oil wells on 40 acre spacing. Initial oil-in-place was 118 million stock tank barrels and initial well potentials averaged 2,000 barrels per day.In early 1956 studies of hydraulic interference between the Acheson and Leduc D-3 Pools were conducted on the Carter Petroleum Reservoir Analyzer. These studies indicated that the natural water drive to Acheson would be incapable of replacing reasonable withdrawal rates over the life of the pool. To avoid shrinkage losses a scheme of pressure maintenance by water• injection was therefore instituted in March 1957.This pressure maintenance scheme is notable because pressure is being effectively maintained by high volume injection through one well located on the flank of the pool. Close control on reservoir behaviour is maintained by regular bottom-hole pres-sure surveys and observation of water cuts on producing wells. No evidence of pressure gradients or channelling of the injected water has been observed to date, and the water-oil contact has remained level over the whole field. It is possible to control the average reservoir pressure within very close limits by varying the rate of fresh water injection.Ultimate recovery estimated from the rise of the oil-water contact and calculated water influx to December 31, 1958, is 335 barrels per acre foot, or a total of 91.4 million barrels from the pool. This compares to 217 barrels Per acre foot or a total of 59.4 million barrels indicated from laboratory test data."

Jan 1, 1961

By Carolina Achiardi, Álvaro Videla

"In pre-design a flotation plant copper sulphide is useful to apply a simplified methodology of economic analysis that relates the size of the grinding product (P80) with the throughput and their effect on copper grade and recovery of copper in the final concentrate of a flotation circuit. With this objective, this methodology covers the following analysis, perform by evaluation of five sizes grinding products (P80): 120, 150, 180, 210 and 240 microns. • Flotation testwork (rougher kinetic, open and closed cycle test) has been done to determinate the optimum operating conditions and to estimate the maximum recovery of copper in the concentrate, using Klimpell model • Flotation plant design assumes a conminution product obtained from a 25,000 HP ball mill • Metallurgical balance is performed for the circuit based on flotation testwork • Economic evaluation by calculating capital expenditure (CAPEX), operating expenditure (OPEX) and sales revenue, to determine NPV is performed and relates to the NPV. An optimum grind size is then obtained based on cash flow. The results shows a grinding product size that optimizes flotation and allows a higher NPV and INPV over other alternatives."

Jan 1, 2014

By M. B. Boyer, C. H. Herty, F. A. Hartgen, G. L. Frear

"DEFINITION OF VISCOSITYViscosity has been defined as the resistance experienced by one portion of a liquid moving over another portion, such as one molecular plane moving over an adjacent plane. A measure of viscosity is the force required to keep one plane in motion at Unit velocity, the other plane being considered stationary. Figure 1 illustrates the general idea that the surface friction between two adjacent areas will be greater the larger the molecules. Therefore it may be assumed that viscosity will be increased by molecular association or agglomeration, and likewise dissociation rill decrease viscosity. According to Maxwell (1)6 the unit of viscosity, the poise, is the tangential force per square centimeter of area of either of two horizontal planes 1 centimeter apart, one of which is fixed while the other moves with unit velocity, the space between being filled with viscous liquid of unit viscosity.The need for a satisfactory apparatus and experimental procedure for the determination of viscosity of high-melting materials at temperatures corresponding to those in pig-iron and steel making has been recognized during the past few decades. The condition of the slag during the smelting and refining periods in the iron- and steel-making processes exerts an important influence on the metal product obtained, this slag condition really meaning the state of viscosity or, vice versa, fluidity, which the slag attains under certain conditions."

Jun 1, 1934

By A. T. Churchman

The deformation modes of rhenium have been identified as those typical of the hexagonal metals, titanium, zirconium, and beryllium whose c/a ratios, in common with rhenium, are less than ideal for close packing. Slip is observed on (1010), (1011), and (0001) planes and twinning on (1121), (1122), and (1012) planes. The very high rate of work hardening is believed to be associated with intersecting partial dislocations on two (1010) systems which can combine to form sessile barriers. If the stacking fault energy is low, as postulated by Seeger, these barriers should be strong and not easily bypassed by cross slipping. Such an explanation could also account for the very small temperature dependence of the yield stress which was observed. RHENIUM is interesting scientifically as a member of the group of high melting point hexagonal metals: titanium, beryllium, and zirconium with a c/a ratio less than that for ideal close packing. Unlike them, however, it work hardens at a very high rate. This rate is greater and continues to a much higher degree of deformation than for nickel, normally considered to have a high rate of work hardening. This paper presents experimental observations on the modes of deformation of rhenium and, by comparison with other hexagonal metals, some speculation on the cause of the high work hardening. MATERIALS Johnson, Matthey rhenium powder of both 99.9 pct and 99.5 pct purity, see Table I, was compacted at 10 tons per sq in., part sintered at 1350°C in vacuo, and finally arc melted in a "gettered" argon atmosphere arc furnace to produce small buttons. Little difference was observed in the as-cast hardness or working down behavior of the two purities suggesting that either silicon and potassium do not have a significant effect on the working properties of rhenium or they were lost during arc melting. SPECIMEN PREPARATION The cast structure was broken up by cold-rolling with inter-stage annealing at 1600o or 1800°C in a vacuum high-frequency furnace using a tungsten susceptor. Strip for tensile testing was taken from two thicknesses of material 0.011 and 0.064 in. The former with intermediate anneals at 1800°C had a grain size of 900 grains per sq mm, while the latter with inter-stage annealing at 1600°C had a grain size of 3600 grains per sq mm. A coarse grain size was obtained by secondary recrystallization in a half button cold-worked by 30 pct reduction. Annealing times of from half an hour to several hours at 2200° to 2600°C in a "gettered" argon atmosphere arc furnace1 resulted in grains of up to 2 mm diam.

Jan 1, 1961

In 2011, the value of mineral production increased in the United States for the second consecutive year (Table 1). Production increased modestly for most mineral commodities mined in the United States, and price increases, especially for precious metals, resulted in increases in the value of production. Minerals remained fundamental to the U.S. economy, contributing to the real gross domestic product (GDP) at several levels, including mining, processing and manufacturing finished products. Minerals? contribution to the GDP increased for the second consecutive year. Trends in other sectors of the domestic economy were similar to those in mineral production and consumption rates. U.S. apparent mineral consumption (industrial) of 11 mineral commodities decreased substantially from 2005 to 2010 (aluminum, cadmium, cement, copper, iron, lead, salt, soda ash, steel, tin and zinc). Data for 2011 were not calculated, but the data show a sustained decrease (especially for the metals) preceding the recession through 2010, so consumption seems to be behaving differently than production and GDP. After continued decline following the 2008?2009 recession, the construction industry began to show signs of improvement during 2011, with increased production and consumption of cement, construction sand and gravel, and gypsum ? mineral commodities that are used almost exclusively in construction. Crushed stone production, however, continued to decline.

Jan 1, 2012

By D. F. Malan, P. J. Le Roux

Almost no work has been published on the strength of pillars in mines exploiting the LG6/LG6A chromitite bands in the Western Bushveld Complex. The strength of these pillars is unknown, and the hard rock industry still uses the Hedley and Grant formula. Numerical modelling, using inelastic constitutive models, may be of some value in estimating the pillar strength, but this approach is difficult and prone to errors as many assumptions are made. This paper explores the alternative approach of the back-analysis of actual LG6/LG6A mining layouts, using displacement discontinuity codes to simulate the average pillar stresses on a mine-wide scale. From this, and underground observations, a ‘minimum’ pillar strength (K-value in the pillar strength formula) can be estimated. The codes TEXAN and Map3D are both used in the paper to simulate the actual pillar shapes and sizes in an LG6/LG6A mine. The results are encouraging as the two codes produced similar APS values for a complex pillar geometry. An estimated K-value of 77 MPa was determined for the LG6/LG6A pillars in this particular area. This is more or less similar to earlier work done for the UG2 chromitite seam, but higher than the K-value of 39 MPa for a linear formula obtained by other workers for LG6/LG6A pillars. Caution should therefore be exercised before using this higher value for all areas. The effect of element sizes and explicitly simulating the effect of the surface for shallow pillars is illustrated in the manuscript using both codes. The need for actual pillar observations and an iterative design process, which cycles between modelling and observations, is also emphasized.

Nov 27, 2024

By C. E. Sims, G. A. Lillieqvist

The following presentation is more a summation of observations made and conclusions drawn over a period of three to four years than a report of experiments made with a definite objective. Tests were made, of course, to verify hypotheses, but the large mass of data was collected incidental to other work. Lack of space forbids the presentation of more than a few of those data. On the other hand, it is unfortunate that some of the most illustrative examples are not available. The work is admittedly incomplete but is presented in the hope that it will stimulate further work along a similar line. The answers to many of the questions left unanswered by this paper will be found only after long and painstaking study, such as is scarcely possible in a commercial laboratory where problems of immediate importance consume most of the time. It is also hoped that this study will in some measure throw light on some of the dark spots of steelmaking, and help to clarify some of the annoyingly vague references to "good practice." Only cast steel was studied and the conclusions apply to cast steel, but it is the authors&apos; opinion that the quality of rolled or forged steel is largely dependent on the quality of the ingot, which is a casting. Although this discussion deals almost entirely with inclusions, it is important that the reader understand that only those natural inclusions which owe their origin to the solubility of certain materials in steel and to the chemical reactions of steelmaking are considered. Accidental inclusions, such as entrapped particles of slag, nozzle, runner, or mold arc outside its province and are not considered. Such accidental inclusions are always dangerous and should be carefully avoided. Relation between Ductility and Nonmetallic Inclusions In September, 1928, an acid electric furnace was put into operation at the Indiana Harbor plant of the American Steel Foundries. Following the usual practice, aluminum additions were made in order to obtain sound castings. Immediately the problem of low ductility arose. Previous to that time, only open-hearth steel was produced, and, aluminum being used rarely in that steel, there had been practically no trouble with low ductility in the lower carbon range.

Jan 1, 1932

By E Coffison, M Gibbs, C Bennett

The sustainable management of surface water associated with coal mining and coal seam gas projects is a considerable factor affecting the global competitiveness of these resource companies operating in Australia. Management of surface water can be costly, but effective water management and hence environmental stewardship enhances corporate social responsibility and the social license to operate. The surface water issues for the two industries are comparable, yet there is currently a lack of alignment between how Queensland, where the majority of AustraliaÆs coal seam gas projects are located, manages and regulates water on coal mine projects and coal seam gas projects.This paper provides a high level comparison of Queensland legislation and highlights the lack of alignment of this legislation regarding surface water management in these two industries. Through a case study, it looks at the surface water management process at a coal mine site based on the current legislation and principals of surface water management. QueenslandÆs lack of alignment in legislation regarding surface water management in these industries is understandable given the different development paths and time scales of the two industries. The coal mining industry has developed over a long period of time and the legislation has progressed in parallel, whereas, the coal seam gas industry is relatively new in Australia and the legislation has had to advance quickly. The lack of alignment between management of surface water for the two industries creates confusion among stakeholders and this adds complexity and additional transaction costs during the exploration, permitting and operational phases of projects, including landowners who may be affected.CITATION:Bennett, C, Coffison, E and Gibbs, M, 2013. Lack of alignment between regulation of surface water management in coal mining and coal seam gas, in Proceedings Water in Mining 2013 , pp 157-162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By K. K. Kelley

Sodium-aluminum and potassium-aluminum silicates are among the more important rock-forming minerals of the earth&apos;s crust. They also appear as constituents of some metallurgical slags and of some refractory materials. Consequently, knowledge of their thermodynamic properties is interesting and valuable from several viewpoints. This paper reports experimental determinations of the low-temperature heat capacities and entropies at 298.16° K. of albite, jadeite, and nephelite it the sodium-aluminum silicate series and of adularia, ferriferous orthoclase, leucite and kaliophilite in the potassium-aluminum silicate series. Also high-temperature heat-content and entropy increments about 298.16° K. are reported for albite, jadeite, nephelite, and carnegieite in the sodium-aluminum silicate series. Except for a few high-temperature heat-content values for albite, all these data are available for the first time.

Jan 1, 1953

By Z. Hyder, M. D. Cleason

"INTRODUCTION Mine Ventilation has come a long way over the years. The main purpose of mine ventilation is to keep conditions in the mine safe for the worker so that the mine will be productive and profitable. Technological developments to the mine ventilation system itself and the development of mining techniques have helped improve the safety and productivity of the miners and the mine. Most of the developments to mine ventilation and to safety devices came as the result of serious mining disasters. Another effect of those mining disasters, especially in the late 19th century and after, was legislation to set specific safety standards for mines, especially in the underground coal mines. This paper will focus on the connection between mines disasters and the mine safety legislations promulgated because of those disasters. A BRIEF HISTORY OF MINE SAFETY LEGISLATION Mine legislation has a long history in the U.S. dating back well in the 1800’s. However, mine safety legislation is considerably newer. In 1891, the U.S. Congress passed the very first version of mine safety legislations setting up minimum safety standards. By today’s standards, the 1891 legislation was incredibly basic (7). It took a series of horrific mining disasters for Congress to take action a second time. In 1910, Congress established the Bureau of mines. The role of Bureau developed and changed over next 60 years. In 1995, Congress voted to disband it (27). Initially the Bureau was only charged with investigating and coming up with ways to reduce accidents in coal mines. It was not until 1941, when Congress formally allowed Bureau of Mines’ Inspectors into the mines. In 1947, the Congress enacted and adopted a set of federal safety regulations for the inspectors to follow (1). Finally, in 1952 Congress granted the Bureau of Mines the authority to inspect the mines and to issue citations and/or orders of withdrawals. This act was known as the 1952 Coal Act and the penalties were limited to civil penalties. It would take a couple more iterations of mine safety legislation for monetary and criminal penalties to be introduced (10). Up until 1966, mine safety legislation was directed primarily at underground coal mines and surface coal mines. Congress passed the Federal Metal and Nonmetallic Mine Safety Act of 1966, thus providing a set of standards for all mines to follow (1). The 1952 Coal Act was amended again to be the Federal Coal Mine Health and Safety Act of 1969. This amendment was the beginning of modern mine safety legislation (13). In 1973, Congress created what can be considered the first ‘version’ of the modern day MSHA (Mine Safety and Health Administration). The initial version was the Mining Enforcement and Safety Administrations or MESA. Congress created MESA to act as the enforcement agency, relieving the Bureau of Mines of that responsibility so they could focus on their initial purpose, the development of countries natural resources (14). As mining industry grew, mine safety and health became a greater concern and priority. More efforts were put in legislating the industry. The Federal Mine Safety and Health Act of 1977 provided the platform for today’s mine safety and health legislation. Under the Federal Mine Safety and Health Act of 1977, also known as the Mine Act, MSHA came into being (1)."

Jan 1, 2016