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To reduce air be respirable dust generated from emptying dry dust collectors on small truck-mounted drills used at surface coal mines.

Jan 1, 1995

1. In 2003, a total of 258 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA). Metal mines were the smallest mining sector, comprising 1.8% of all mining operations.1 • Gold mines comprised 44.2% (n = 114) of all metal mining operations. Other common types of metal mines were iron ore (n = 29; 11.2%), copper ore (n = 28; 10.9%), and lead and/or zinc ore (n = 21; 8.1%). • Nevada had the largest number of metal mines (n = 48; 18.6%) followed by Alaska (n = 29; 11.2%).

Feb 1, 2005

By Charles Vaught, Michael J. Brnich, Henry P. Cole, John V. Haley, William J. Wiehagen

Forty-eight workers who bad escaped large underground coal-mine fires were interviewed using an open-ended protocol. This information, and the actual experiences of one eight-person mine-section crew who escaped from a Fire, were used to construct an 18-frame (page) table-top simulation exercise, which was then field tested with 134 miners. The exercise is a research toot that measures miners' proficiency in the information-gathering and decision-making skills related to escaping from a mine fire. It also helps miners to learn and practice these cognitive skills. The exercise was found to be valid and reliable. All miners reported that the exercise was authentic and would help them to remember important information. The exercise total score, and all but two item scores, significantly discriminated among miners with different levels of training. The two items that did not discriminate dealt with whether or not to abandon a helpless fellow miner. When the exercise total score data were pooled, only 13.6% of the miners achieved a desirable score of 90% mastery or greater. The simulation is important because it teaches and assesses critical judgment and derision-making skills that are rarely addressed in miner training. Index Terms- Coal mining, critical skills, decision making, emergency escape and evacuation, escape from fire judgment training, mining, safety training, simulation training, under-ground mine fires.

By K. L. Cashdollar

A project to evaluate the South African bagged stone dust explosion barrier was successfully completed at the National Institute for Occupational Safety and Health (MOSH), Pittsburgh Research Laboratory's (PRL), Lake Lynn Experimental Mine (LLEM) during the period November 1999 through May 2000. The tests were conducted in a three- entry section of the LLEM. Two types of explosions were used to evaluate the distributed and concentrated bagged barrier performance in a multi-entry mine section. The fuel zone of the first explosion type was only in the center B-drift. In the second explosion type, coal and stone dust mixtures were place in all three drifts. A total of six explosions, including two baseline and four barrier evaluation explosions, were conducted. Of the four barrier explosions, the distributed and concentrated barriers were each evaluated against the two explosion types. For these explosion tests, the distributed barrier extended from about 74 to 170 m and the concentrated barrier from about 74 to 104 m in B-drift. The distributed barrier successfully stopped flame propagation in both types of explosion tests. The flame extended further for the explosion tests where the dust was loaded in all three entries compared with dust loaded only in the center entry% but in both cases the flame was stopped within the barrier zone. The concentrated barrier was also successful in stopping flame propagation m both explosion tests. From the full-scale experimental mine test results, it can be concluded that both bagged barrier designs were effective in stopping coal dust explosions in the multiple entries of the LLEM.

By D. Harringtong

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

Jun 1, 1932

This surveillance report summarizes data on work-related fatal and nonfatal injuries, illnesses, and hazardous exposures in the mining industry for the 10-year period 1986-1995. The term "surveillance," as used in public health, may be new to many readers of this report. With regard to occupational safety and health, the goal of surveillance is to describe the occurrence of work-related injuries, illnesses, and known hazardous exposures; to identify new hazards that may occur due to the introduction of new technology or other factors; and to assess the effects of preventive measures designed to improve worker safety and health. Surveillance provides an overall picture, which can be used to focus resources on areas most in need of prevention programs or further research. Surveillance generally requires the use of multiple sources of data, all of which have their own strengths and limitations. Surveillance in the U. S. mining industry is complicated by the fact that U.S. national data systems that provide information on mining are based on two different definitions of the mining industry. One is established by the Mine Safety and Health Administration (MSHA), the other by the Standard Industrial Classification (SIC) System [Office of Management and Budget 1987] and the 1980 U. S. Bureau of the Census (BOC) Classification System [U.S. Bureau of the Census 1982]. The mining industry as defined by MSHA is based on the regulatory jurisdiction of that agency. Reporting requirements for injuries, illnesses, and workplace exposures are stipulated under the Federal Coal Mine Health and Safety Act of 1969 and the Federal Mine Safety and Health Amendments Act of 1977. Of note is that the oil and gas extraction industry falls outside of MSHA jurisdiction. The Occupational Safety and Health Administration (OSHA) was charged with enforcement in the oil and gas industry under the Occupational Safety and Health Act of 1970. Under the SIC, the definition of mining covers the extraction of naturally occurring minerals, including liquids (petroleum), gases (natural gas) and solids (coal, metal, and nonmetallic minerals). Exploration and development of mineral properties are also included in the SIC definition of the mining industry. The SIC was developed by the Office of Management and Budget for use in classifying establishments based on the type of economic activity in which they are engaged and serves as the industry classification standard for all establishment based Federal economic statistics. This classification is important for occupational safety and health surveillance because it also serves as the industry classification system for all data on work-related injuries and illnesses collected by the U.S. Bureau of Labor Statistics (BLS). The U.S. Bureau of the Census uses an industry coding scheme similar to that used by the SIC. For the mining industry, the categorization is identical in both systems. Death certificate data made available by the National Center for Health Statistics (NCHS) are categorized under this system. Death certificate data are particularly important for surveillance of mortality from work-related illnesses. Key differences between the SIC/BOC categorization system and the MSHA system can be summarized as follows: • MSHA excludes the oil and gas industry, which is classified as part of the mining industry under SIC/BOC. • MSHA excludes work that is done off of mine property; work off of mine property is included under SIC/BOC if it is performed by an establishment falling into one of the SIC/BOC mining industry codes. • MSHA includes mine-associated mills and processing plants; these are classified under the manufacturing industry, rather than mining, according to the SIC/BOC coding structure. Since the data collected by MSHA and the data collected by BLS and NCHS using the SIC/BOC classification system are both important sources of information on the mining industry and in many cases serve different purposes, data from both systems are presented in this report. In general, data using the SIC/BOC system are comparable across U.S. industries and should be used when comparing mining to other U.S. industries. Much of the data in this report are presented in the form of frequencies or rates. A frequency provides only a count of the number of cases without providing any information about the risk of occurrence. Rates provide an estimate of the risk of injury or illness. The reader is cautioned, however, that rates based on small numbers can be unstable; thus, any inferences should be drawn with care. In this report, no rates are presented for groups in which there were fewer than three cases. The incidence of most injury and illness conditions differs by age, sex, and race. For this reason, data in many surveillance reports are adjusted for these demographic factors. It was not possible to do this for most of the rates in this report because information on demographics was not available. With the exception of the proportionate mortality ratios (PMRs), all data presented are unadjusted. A detailed account of the sources of data is in appendix A. The methods used in data selection and analysis are described in appendix B.

Jan 5, 2000

The title of this book, The Phoenix of Natural Disasters: Community Resilience is aptly chosen. ?The Phoenix is a mythical bird that never dies; the phoenix flies far ahead to the front, always scanning the landscape and distant space. It represents our capacity for vision, for collecting sensory information about our environment and the events unfolding within it.? (source: The Feng Shui Handbook, feng shui Master Lam Kam Chuen.) There are Chinese, Japanese, Russian, Egyptian, and Native American counterparts of the phoenix. All of these birds are identified with the sun and depicted as rising from the ashes ? living again. This is the essence of a community after a natural disaster ? they live again. The Phoenix of Natural Disasters: Community Resilience is edited by Kathryn Gow and Douglas Paton who have done an excellent job of creating a relatively seamless transition between chapters with different authors. The content is organized well with the first chapter providing an excellent overview of what is to come and each chapter including an abstract clarifying the focus of the chapter.

Jan 1, 2009

By A. J. Hudson, M. R. Yenchek

Faulty insulators on mine trolley/track haulageways may allow the flow of leakage currents into the mine roof and ultimately result in combustion of the local roof material. The National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Laboratory (PRL), has devised a passive means to detect overheating insulators on direct current systems. The detector consists of a spring-loaded cartridge that ejects a reflective streamer of white Teflon tape when subjected to elevated temperatures. The cartridge assembly can be easily installed over the outer metallic shell of an existing trolley line insulator. If an insulator overheats due to ground leakage currents, the visible streamer alerts mine personnel traveling on the haulageway.

By E. William Rossi, Sean Gallagher, Richard L. Unger

The purpose of this study was to examine the lifting capacity of low-seam coal miners in four restricted work postures (roof heights of 36", 40", 44", and 48"), investigate the associated metabolic costs, and to examine electromyographic (EMG) data from eight trunk muscles during the lifting procedure. Subjects were thirteen underground miners accustomed to handling materials in restricted work postures. Each subject performed two twenty-minute periods of asymnetric lifting in each of four postures during the day of testing. The. frequency of lifting was 10 lifts per minute. A specially designed lifting box incorporated microswitches in one handle of the box and another in the bottom of the box, in order to examine the trunk muscle function at specific points during the lfting cycle. The data collected will be used by the Bureau of Mines to make recommendations for lifting materials in low-seam coal mines.

By Jeanne A. Zimmer, Charles D. Taylor, Edward D. Thimons

Strategies for monitoring methane levels during roof bolting in an extended cut entry were evaluated. Testing was conducted at the Pittsburgh Research Laboratory’s methane test gallery. Operating conditions were varied and methane releases at the face and drill holes were simulated. Methane readings were taken at the face, and at locations outby the face. Results show that, when the major source of methane was at the drill holes, the highest methane readings were at locations on or 6.1 m (20ft) inby the bolting machine. Methods for selecting better outby sampling locations, when the majority of the methane is released at the face, are examined. During roof bolting it is easier to sample at these outby locations rather than at the face. Further testing is needed to determine what relationship exists between methane concentrations at the outby locations and at the source of the methane release.

By Sinisa M. Djordjevic, Isaac A. Zlochower, Kevin J. Liekhus, Cindy A. Loehr, Kenneth L. Cashdollar

An experimental program was conducted to evaluate the accuracy of some current methods for predicting the flammability of gas mixtures containing hydrogen and flammable or nonflammable volatile organic compounds (VOCs) in air The specific VOCs tested were toluene, 1,2-dichloroethane, 2-butanone, and carbon tetrachloride. The lower flammability limits (LFLs) of gas mixtures containing equal molar quantities of the components were determined in a 19.4-1 laboratory flammability chamber using a strong spark ignition source and a pressure criterion for flammability. All but one of the LFL values for the individual components were in agreement with earlier literature values. However, the LFL of l,2-dichlorocthane was found to be significantly lower than the range of values reported for previous determinations in smaller chambers. Two methods for calculating the LFL of mixtures were considered. The Group Factor (atomic) Contribution Method was determined to he generally more accurate than the LeChatelier Method for estimating the LFL of the gas mixtures reported here, although the LeChatelier Method was usually more conservative. The Group Factor Method predicted higher values (nonconservative) for the LFLs of several mixtures than were experimentally measured. For the case of a mixture of hydrogen and carbon tetrachloride, the Group Method estimation of the LFL was seriously in error.

By John J. Sammarco

Mining, traditionally a low-tech industry, is now utilizing surprisingly complex programmable electronic (PE) systems. The functional safety of PE-based mining systems is an international issue and concern. From 1995 to 2001, there were 11 PE-related mining incidents reported in the U.S. and 71 PE-related mining incidents reported in Australia. These incidents are due, in part, to unprecedented levels of system complexity. The National Institute for Occupational Safety and Health (NIOSH) is addressing this issue of system complexity by conducting research to develop a quantitative complexity assessment methodology based on Normal Accident Theory (NAT). The methodology models the behavioral interactive complexity at the level of system requirements. A graph-theoretical approach is used for creating quantitative metrics from Software Cost Reduction (SCR) dependency graphs. This complexity assessment methodology will help realize simpler, safer systems that will be easier to validate and verify. The methodology will benefit mining and other industries as well.

By Jürgen F. Brune, William H. Schiffbauer

Communication problems are not new. Research in this area goes back as far as 7922 when the US Bureau of Mines performed experiments to detect radio signals from inside their experimental mine in Bruceton, Pennsylvania. Many improvements to mine communications have been made over the years but for any number of reasons the underground coal mining industry has been behind in implementing advances. Present communications systems far underground mines can be hard-wired or wireless. Both types of systems can fail when faced with fires, roof falls, explosions, and power or battery failure. Currently installed wireless communications systems usually employ a special antenna cable called a "leaky feeder" Fiber optic cables are also used in some applications to form a "backbone" for wireless transceivers. Through-the-earth (TTE) and wireless radio systems are less common. Except for TTE systems, most wireless systems require some wire-bound components, which are susceptible to failure during disasters as cable breakage interrupts communications.

By Rudolf E. Greuer, Linneas W. Laage, Xinton Chang

The usual run time errors occur when illegal mathematical operations are attempted by MFIRE For exam¬ple, if the user enters a negative value for the input variable HEAT to model a heat sink or cooling station, a run tame error will occur because an exponential function is employed to better model the changing temperature dis¬tribution in the airways. DATA FILE ERRORS Two types of data file errors can occur. 1 An error may occur because the input data file itself is invalid This may be caused by: The data file cannot be found due to incorrect spelling, drive, or path specification Check the spelling and path at the prompt for location of the data file. The data file contains non-ASCII symbols Check op¬eration of the text processor to insure that only ASCII characters are produced Delete all non-ASCII and/or all out of place characters. 2 Data are accepted by the program, but are incorrect for the data types or ranges or the combination causes a data inconsistency This may be due to. An invalid character is located where a numerical value is required The input data value is outside the reasonable range The input data is insufficient to build the model for simulation. The input data exceeds the capacity of the program. PROGRAM ERROR DETECTION When the program is running, tracing messages are given on the screen indicating the group and lines of data that have been read and the section of the program that is executing Program termination indicates that problems are caused by the subsequent (not read) data file section. For each detected error, descriptive message starting with * ERROR * is issued and the program terminates. When a possibly wrong value and/or its calculated intermediate result is detected, a descriptive message starting with * WARNING * is issued and the program continues. If a modification of input value or calculated intermediate result is automatically made by the program, descrip¬tive message starting with * ATTENTION * is issued and the program continues. LOCATING ERRORS If a message indicates that the error condition occurred due to the data input file, locate and correct the data item. If no error message is issued, but the simulation results are not as expected, carefully check the list of input data shown in the output file WARNING messages and ATTENTION messages may reveal an error in the input data even though the program continues to operate Insure that the default values or modifications adopted by the program run are acceptable. Anomalistic data, though not incorrect or impossible, may lead to an unusual simulation For example, making a fan unusually powerful may prevent a normal strength fire from affecting the airflow distribution in the system Much care must be employed before considering an ex¬treme case. If a message indicates that the accuracy criterion in the temperature section of the program was not satisfied, a table detailing the current parameters of airways which have large fluctuation in the average air temperature from iteration to iteration is produced If the pattern of the parameters is clearly cyclical, while the variation of natural ventilation pressure is stable or cyclical from iteration to iteration, then, most likely there is no single equilibrium stage for the event If the variation of natural ventilation pressure decreases steadily though slowly, increasing the value of data item variables MADJ or ITN (on control line number 1) may allow convergence.

Jan 1, 1990

By J. J. Bourquin

"The Keely mine at Dagger, Indiana, is one of the few mines that is being operated successfully on a cooperative basis. This shaft mine is developing 133 acres of coal in the Indiana No. 6 bed, which here averages 5-1/2 feet thick and. lies about 110 feet below the surface. Thirty seven (37) miners and twenty (20) company men or day man are employed, and the daily output is around 300 tons. Practically the entire production is sold by contract for railroad use. No mining machines are used and all coal is produced by pick work.The mine was originally owned and operated by the Stockton Coal. Co. of Dugger, but about eight years ago it was leased to Mr. Roy Price. He sub-leased the property to ten miners, who formed an association known as the Dugger Mutual Coal and Mining Co., to work the mine cooperatively.At first many difficulties were encountered; the cooperative idea is an old one, but the practice was new to those interested. Some of the men were energetic, ambitious workers; others were inclined to let their associates produce the coal but wanted to share in the profits. In time, after a hard struggle and many changes in the personnel of the company, business-like methods were adopted and the mine was put on a paying basis."

Feb 1, 1983

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.

To provide a practical method to reduce hand and arm injuries during roof bolting operations.

Jan 1, 2000

By John N. Murphy

In fiscal 1996, the US Congress directed that the US Bureau of Mines (USBM) be closed. Certain functions were reassigned to other agencies. The remaining employees were separated and the unoccupied sites were decommissioned. As a result, 12 locations were closed and about 1,200 employees were terminated in March 1996. About 600 employees at five locations were reassigned to other federal agencies. This article provides a summary of the continuing functions, the agencies involved and the points of contact for each continuing function. The functions that were discontinued are also identified.

RI 9527. Effective Hazard Recognition Training Using a Latent-Image, Three-Dimensional Slide Simulation Exercise, by E.A. Barrett and K.M. Kowalski. Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, 1995. NTIS stock number: PB95-170379. Rl 9531). Computer Modeling and Analysis of The Greens Creek Mine, Admiralty Island, AK, by MJ. Beus and T.J. Orr. Spokane. WA. -U.S. Department of the Interior, Bureau of Mines. 1995. NTIS stock number: PB95-176418. RI 9600. Application of Field Measurements and Computer Modeling to Evaluate Deep Mine Shaft Stability in Northern Idaho, by M, J. Beus, T. J. Orr and J. K Whyatt. Spokane, WA: U.S. Department of the Inferior. Bureau of Minus. 1996. NTIS stock number: PB96-140181. [ ]

Jan 1, 1995

By Frederick C. Trutt, Jeffery L. Kohler, Joseph Sottile

Condition-based maintenance (CBM) of industrial equipment is generally recognized as being the most cost-effective means for improving equipment availability. However, prerequisite to successful implementation of CBM is a reliable detector of failing components. One such detector, termed the effective negative-sequence impedance, had previously been identified as an indicator of induction motor stator winding degradation. However, a limitation of this detector is that it does not change in a predicable manner under certain motor operating conditions. This paper presents an experimental investigation of an improved technique for on-line detection of induction motor stator winding degradation. The paper begins with a brief description of the detectors, followed by a detailed description of the experimental setup, the experiments conducted, and results.