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- Keyword
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- Abandoned Coal Mine; Golden Eagle; Coalbed Methane; Gas Production; Coal Mine Methane; Numerical Modeling; Overburden Relaxation; Gas Migration (1)
- Air Changes; Slate; Strip and Block Saws; Chimney Fan; Silica; Respirable Dust (1)
- Area Ratio; Flow Ratio; Entrainment; Momentum; Energy; Pressure; Jet Mixing Length; Mixing Velocity; Performance; Losses; Efficiency (1)
- Auxiliary Ventilation; Duct Leakage; Leakage Coefficient; Leakage Prediction Techniques (1)
- Axial Flow Fan; Blade Pitch; Block Caving; Production Level; Haulage Level; Intake Shaft; Exhaust Shaft (1)
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- Barrier; Explosion; Film Destruction; Methane Concentration; Shock Wave (1)
- Cab; Dust Control; Mobile Equipment; Quartz; Respirable Dust; Environmental Cab (1)
- Coal Face; Longwall Shearer; Dust Level; Physical and Mechanical Properties of Coal; Operational Parameters (1)
- Coal Mining; Continuous Mining; Dust Control; Dust Exposure; Personal Exposure; Dust Sampling; Personal Sampling; Fixed-point Sampling (1)
- Coal; Dust; Underground; Explosions; Risk; Protective; Preventative; Management (1)
- Coal; Methane; Mining; Ventilation; Combustion; Regenerative; Greenhouse Gas (1)
- Coal; Thin-seam; Ventilation; Panel Layout (1)
- Coalbed Methane; Degasification; Downtime; Methane Drainage; Room-and-pillar Mining; Ventilation Economics (1)
- Coalbed Methane; Degasification; Methane Drainage; Reservoir Simulation; 3-D Model; Vertical; Degas; Permeability (1)
- Computational Fluid Dynamics (CFD); Scale Model; Pressure Measurements; Auxiliary Ventilation (1)
- Computational Fluid Dynamics; Diesel Exhaust; Fire Heat Release Rate; Overbuild; Simulations; Transit Station; Tunnel Ventilation (1)
- Computational Fluid Dynamics; Mine Fire; Smoke Spread; Flow Reversal (1)
- Conductivity; Diffusivity; VRT; Heat Flow; Lucky Friday Mine (1)
- Controlled Recirculation; Deep Gold Mine; Conceptual Model (1)
- Design; Fans; Air Volume; Air Distribution; Operating Cost; Airflow Control (1)
- Diesel Exhaust; Diesel Particulate Matter; Fuel Additive Properties; Catalytic Converter (1)
- Diesel Particulate Matter (DPM); Coal Mining; Exposure; Filtration; maintenance; Ventilation; Enforcement; Health and Safety; Engine; Testing (1)
- Direct and Inverse Problem; Convective Diffusion; Linear Accumulation; Integra-Differential Equation; Dimensionless Absorption Coefficient; Dimensionless Accumulation Coefficient (1)
- Dust Extraction; Dust Explosions; Dust Hazards. Methane; Health Protection; Pneumoconiosis; Wet Dust Collectors; Vortex Ventubes; Combined Ventilation System; Exhaust Ventilation (1)
- Dust Extraction; Dust Explosions; Dust Hazards; Methane Hazards; Health Protection; Pneumoconiosis; Wet Dust Collectors; Vortex Ventubes; Combined Ventilation System; Exhaust Ventilation (1)
- Dust Sampling; Airborne Dust; Instantaneous Dust Sampler; Dust Deposition; Mechanized Coal Face; Middle Anatolian Lignite Mine (1)
- Dust Suppression; Sprays; Half-Curtain; Force/Jet Fan; Continuous Miner; Underground (1)
- Early Warning; Fire Detection; Discriminating; Diesel Engine; Carbon Monoxide; Nitric Oxide; Ambient; Alarms (1)
- Electromagnetic Radiation (EMR); Acoustic Emission (AE); Coal Fracture; Coal and Methane Outburst; Rock Outburst (1)
- Emissions; Diesel Engine; Sootfilter; Catalyst; Exhaust Aftertreatment; Cerium; Particulate Matter; DPM; Regeneration (1)
Articles 61 - 90 of 103
Full-Text Articles in Mining Engineering
Economic Analysis Of Coalbed Methane Drainage Systems For Room-And-Pillar Operations, Yanbei Wang, Jan M. Mutmansky
Economic Analysis Of Coalbed Methane Drainage Systems For Room-And-Pillar Operations, Yanbei Wang, Jan M. Mutmansky
U.S. Mine Ventilation Symposium
The analysis of the economics of methane drainage operations in traditional room-and-pillar coal mining operations is the primary emphasis of this presentation. The paper analyzes the economic effects of ventilation costs versus drainage costs as a means of handling the methane in a hypothetical room-and-pillar operation. However, the effects of downtime savings due to methane reduction in the air stream and the impacts of marketing the methane are also studied. Comparisons are then made with the economics of drainage in longwall mining.
Effectiveness Of Cabs For Dust And Silica Control On Mobile Mining Equipment, Joseph J. Garcia, Ronald E. Gresh, Mary Beth Gareis, Robert A. Haney
Effectiveness Of Cabs For Dust And Silica Control On Mobile Mining Equipment, Joseph J. Garcia, Ronald E. Gresh, Mary Beth Gareis, Robert A. Haney
U.S. Mine Ventilation Symposium
The Mine Safety and Health Administration (MSHA) has conducted a study to evaluate the effectiveness of cabs for controlling silica dust exposure during operation of mobile mining equipment. This study focused on bulldozers, front -end loaders and haul trucks, was conducted at surface coal mining operations and underground metal and nonmetal mining operations. Each piece of equipment tested was equipped with a cab. The vehicles sampled were from a range of manufacturers having different types of filter media and air intake configurations. The purpose of this study was to determine the reduction of dust and silica exposure that could be …
Table Of Contents, Multiple Authors
Table Of Contents, Multiple Authors
U.S. Mine Ventilation Symposium
No abstract provided.
Niosh/Nci Study Of Exposure To Diesel Exhaust In Underground Mines — An Industry Perspective, Christopher J. Pritchard
Niosh/Nci Study Of Exposure To Diesel Exhaust In Underground Mines — An Industry Perspective, Christopher J. Pritchard
U.S. Mine Ventilation Symposium
In 1992, the National Institute For Occupational Safety and Health (NIOSH) initiated a study, funded by the National Cancer Institute (NCI), to evaluate the health effects, if any, involving underground miners exposure to diesel exhaust. An industry organization, the Methane Awareness Research Group (MARG) already in place to respond to gassy mine related issues, was redirected to work with diesel concerns. In 1995, NIOSH released a draft protocol and feasibility assessment, indicating its intent to initiate s study at 14 underground mines, some of which were operated by MARG members. After considerable debate on the study protocol, in-mine industrial hygiene …
Computer Simulation Of Climatic Conditions For Underground Automated Mines For Standard And Reduced Airflow Requirements, Julian Partyka, Stephen Hardcastle, Charles Kocsis
Computer Simulation Of Climatic Conditions For Underground Automated Mines For Standard And Reduced Airflow Requirements, Julian Partyka, Stephen Hardcastle, Charles Kocsis
U.S. Mine Ventilation Symposium
This study demonstrates the importance of ventilation in an automated mine through climatic simulations. These have been performed on workings located at depths of 1000 m to 3000 m below surface in an underground metal mine. Each active working area employs either an electric or a diesel piece of equipment that has a full load power output of 100 kW to 200 kW. The airflows considered in the mining areas were standard full-flow conditions, i.e. 100% (6.5 m3/100 kW), and 125%, 75%, and 50% of full-flow. The analyses show, for instance, that a 100 kW electric machine can increase the …
Author's Index, Multiple Authors
Author's Index, Multiple Authors
U.S. Mine Ventilation Symposium
No abstract provided.
Personal Cooling In Hot Workings, Michael A. Tuck
Personal Cooling In Hot Workings, Michael A. Tuck
U.S. Mine Ventilation Symposium
The number of mines experiencing climatic difficulties worldwide is increasing. In a large number of cases these climatic difficulties are confined to working areas only or to specific locations within working areas. Thus the problem in these mines can be described as highly localised, due to a large extent not to high rock temperatures but due to machine heat loads and low airflow rates. Under such situations conventional means of controlling the climate can be inapplicable and/or uneconomic. One possible means of achieving the required level of climatic control, to ensure worker health and safety whilst achieving economic gains, is …
A Mathematical Model Of Heat Transfer In Partially Insulated Airways In Deep, Frozen Ground Placer Mines, Sukumar Bandopadhyay, Hanguang Wu, Michael G. Nelson
A Mathematical Model Of Heat Transfer In Partially Insulated Airways In Deep, Frozen Ground Placer Mines, Sukumar Bandopadhyay, Hanguang Wu, Michael G. Nelson
U.S. Mine Ventilation Symposium
Large seasonal variations in the temperature of the ventilating air in mines in the arctic cause changes in the original thermal field through heat and mass exchanges between the air and the surrounding medium. These thermal interactions have major influence on climatic quality as well as on the stability of the mine openings. Thawing of walls and roof in mine airways can be reduced by various types of thermal-insulation. Application of thermal-insulation prevents deep thawing of the rockmass surrounding an airway. In this case, the mechanism of heat transfer around a frozen, underground airway would be much different. A model …
The Influence Of Coal Physical And Mechanical Properties And Mining Energy Consumption Factor On Airborne Respirable Dust Level, Antoni Koziel, Malgorzata Malec, Ewa Wardas
The Influence Of Coal Physical And Mechanical Properties And Mining Energy Consumption Factor On Airborne Respirable Dust Level, Antoni Koziel, Malgorzata Malec, Ewa Wardas
U.S. Mine Ventilation Symposium
The fact that there are not any explicitly defined relationships describing the influence of physical and mechanical properties of coal and of energy consumption factor on dust level prompted Polish and American investigators to carry out a joint research project within the framework of the U.S.- Poland Maria Sklodowska-Curie Joint Fund II. The paper presents methods used to perform tests under laboratory conditions at the Pittsburgh Research Laboratory as well as under real conditions in the course of coal cutting in polish coal mines. Measuring systems and results of the tests are described. The analysis carried out has provided a …
The State Of Mining Research In Niosh, R. Larry Grayson
The State Of Mining Research In Niosh, R. Larry Grayson
U.S. Mine Ventilation Symposium
No abstract provided.
Effects Of Drilling Small Diameter Exhaust Shafts In A Gassy Longwall Operation, Tim Coleman, William Maloney
Effects Of Drilling Small Diameter Exhaust Shafts In A Gassy Longwall Operation, Tim Coleman, William Maloney
U.S. Mine Ventilation Symposium
As the title indicates, this paper deals with the ventilation of a gassy longwall mine through the use of small diameter exhaust shafts. Extensive background information is provided to show the evolution of the mine's ventilation system to correspond with changes in longwall mining techniques, particularly increases in face width. A description of the blind drilled shaft techniques, which proved to be the most economical ventilation choice for US Steel No. 50 Mine, is also included.
Ventilation-On-Demand: Quantity Or Quality — A Pilot Trial At Barrick Gold's Bousquet Mine, Stephen G. Hardcastle, M. K. Gangal, Manfred Schreer, Paul Gauthier
Ventilation-On-Demand: Quantity Or Quality — A Pilot Trial At Barrick Gold's Bousquet Mine, Stephen G. Hardcastle, M. K. Gangal, Manfred Schreer, Paul Gauthier
U.S. Mine Ventilation Symposium
Common to many established mines in Canada, is the problem that their ventilation systems are continually being stretched to meet new needs that were not anticipated in the original design. This can be the result of a variety of different factors, such as the discovery of new reserves at depth, accelerated production, new worker exposure regulations or a change of mining method. At Bousquet, the ventilation of a new multilevel mining block over 1 km away from the existing bottom of the mine presents a challenge. The airflow available for this region is limited to 57 m3/s by …
Novel Approach To The Energy Analysis Of Mine Cooling Strategies, C. T. Twort, I. S. Lowndes, S. J. Pickering
Novel Approach To The Energy Analysis Of Mine Cooling Strategies, C. T. Twort, I. S. Lowndes, S. J. Pickering
U.S. Mine Ventilation Symposium
The extraction of minerals and coal at increasing depth, employing higher-powered, mechanized machinery to increase production levels imposes an increased burden on the ability to maintain an acceptable mine climate. Any deterioration in the mine climate within working zones may adversely affect the health and safety of the workforce. The combination of the optimal design of the mine system layout, together with the selective application of suitable ventilation and cooling systems, may be used to control the climate within working zones. The adoption of mechanical cooling within mines is an expensive process in terms of both capital and operating costs. …
Management Of Mine Explosion Risks, Jan J. L. Du Plessis, J. W. Oberholzer
Management Of Mine Explosion Risks, Jan J. L. Du Plessis, J. W. Oberholzer
U.S. Mine Ventilation Symposium
The management of explosions in the underground mining environment has been a high priority for managers since the turn of the century. In the early 1900s explosions, worldwide, reached catastrophic dimensions. In a number of large explosions more than 1000 people have died. In the early years of research, the basics of why explosions occurred were investigated and the participation of coal dust in underground coal mine explosions was proved. Taffanel, a French researcher, was one of the pioneers in establishing the use of stone dust and was instrumental in the design and development of the first stone-dust barriers. Throughout …
Shock Waves Generated In The Presence Of Barriers In Gas Explosions, Baiquan Lin, Shining Zhou
Shock Waves Generated In The Presence Of Barriers In Gas Explosions, Baiquan Lin, Shining Zhou
U.S. Mine Ventilation Symposium
This paper examines conditions that generates shock waves in a gas explosion through experiment. The result shows that the presence of barrier and thin film, which is similar to air door and stopping in underground coal mines, is very important for the generation of shock waves in a gas explosion. When there are physical barriers, the speed of transmission would be very fast and shock waves will result in the process; when the film is destroyed in gas explosion, shock waves will also appear which would result in an increase in explosion power. Therefore, in order to weaken the gas …
Recovery Of Minerales Monclova Minas V, Patrick Graham, William Marston, Donald Mitchell, John W. Stevenson, David Sullivan
Recovery Of Minerales Monclova Minas V, Patrick Graham, William Marston, Donald Mitchell, John W. Stevenson, David Sullivan
U.S. Mine Ventilation Symposium
Methane issuing from a roof-bolt hole ignited when the hot bit was withdrawn. Similar ignitions have occurred in other mines. This one differed in that flames spread quickly, coal was ignited, and, after three futile hours of applying inadequate water and extinguishing agents, the mine was sealed. Fires are fuel and ventilation controlled. In this mine there was an abundance of methane, coal, and wood lagging. Recovery of the mine, therefore, depended on successful control of its ventilation. The recovery was done without anyone suffering a scratch; a remarkable feat considering the abnormal methane outflows and concentrations, the continuing evidence …
Modelling Of Gob Inertization With Nitrogen, Michael Michaylov, Elena Vlasseva
Modelling Of Gob Inertization With Nitrogen, Michael Michaylov, Elena Vlasseva
U.S. Mine Ventilation Symposium
The paper deals with a modelling of nitrogen distribution throughout gob so that the effect of inertization could be measured. The model takes into account flow transient character, methane liberation and different locations for nitrogen injection. Computer modelling, reflecting mathematical models is done by a specially created computer programme NITRO_ GOB, which allows dealing with different parameters of air leakage, of coal waste distribution as well as of gas picture in the gob before inertization. Effective evaluation of the most important parameters - injection place and nitrogen volume- on gob gas picture is illustrated under typical cross-section profiles of gas …
Axial Flow Fan Use At San Manuel Mine, Kuda R. Mutama, Dave P. Pelletier
Axial Flow Fan Use At San Manuel Mine, Kuda R. Mutama, Dave P. Pelletier
U.S. Mine Ventilation Symposium
A case study is presented for the use of multiple axial flow main fans as the principle source of the primary mine ventilation system for a large multi level mine. Formerly owned by Magma Copper, BHP Copper Inc.'s San Manuel Mine is a large underground block caving copper mine which started producing copper in 1955. The San Manuel Mine produces over 50,000 tons per day sulfide copper ore. The total airflow into this mine is approximately 800 m3/s (1,600,000 cfm). Providing adequate ventilation has been a very challenging experience as new, deeper levels are developed. BHP relies on …
Anti-Stall Fans For The Mining Industry, Phil Blankenship, Hakan Bard, Robert Z. Smith
Anti-Stall Fans For The Mining Industry, Phil Blankenship, Hakan Bard, Robert Z. Smith
U.S. Mine Ventilation Symposium
Stable performance of mine ventilation fans is important not only for maintaining adequate ventilation of the mine, but also to maintain the integrity of the fan unit itself. It is demonstrated, herein, that a properly designed and applied stabilization device, integrated into the fan casing itself, will assure stable performance and actually extend the fan's capability.
Improving The Ventilation Efficiency Of Jet Fans In Longitudinally Ventilated Rectangular Ducts, Eddy Jacques, Pierre Wauters
Improving The Ventilation Efficiency Of Jet Fans In Longitudinally Ventilated Rectangular Ducts, Eddy Jacques, Pierre Wauters
U.S. Mine Ventilation Symposium
The performance of a jet fan in a longitudinally ventilated tunnel is significantly reduced by the proximity of wall or ceiling where important shear stress losses occur. The paper focuses on the effect of jet fan inclination on the reduction of these losses; reducing losses means improved installation efficiency manifested by increased ventilation flow for the same fan power input. Experimental tests were carried out on a model at scale 1/5.5th. They allow one to determine the optimal jet pitch angle and the resulting benefit that could be drawn out of this solution in the case of tunnels …
Axial Fan Monitoring By Pressure Transients Close To The Blades, A Preliminary Study, Ian Loomis, Shaun Ramsay
Axial Fan Monitoring By Pressure Transients Close To The Blades, A Preliminary Study, Ian Loomis, Shaun Ramsay
U.S. Mine Ventilation Symposium
As the axial fan blades move within the fan case pressure transients are developed, which can be measured and qualified by a fixed point monitor. The nature of the pressure transient pattern observed close to the fan blade varies with the location on the fan performance curve. Measurement of the pressure fluctuation around the fan blade ring reveals the minute variation in pressure associated with the movement of the air within the fan. Such observations could be the basis for an on-line fan monitoring system based on the acoustic emissions from the fan blade. This paper describes a preliminary study …
Validation Of Computational Models Of Auxiliary Ventilation Systems With Experimental Data, K. W. Moloney, D. M. Hargreaves, I. S. Lowndes, W. Pearce
Validation Of Computational Models Of Auxiliary Ventilation Systems With Experimental Data, K. W. Moloney, D. M. Hargreaves, I. S. Lowndes, W. Pearce
U.S. Mine Ventilation Symposium
This paper reports the interim findings of a research program whose objective is to determine whether Computational Fluid Dynamic (CFD) models can be employed to accurately predict the airflow patterns within rapid development headings. In particular, the project aims to investigate the optimum set back distances for the ducts in order to adequately ventilate the face of the drivage. To validate the accuracy of the CFD model simulations measurements were obtained from a series of experiments performed on both scale models and within a full-scale surface gallery. The experimental scale-modeling program included making a series of pressure measurements across the …
Environ 2.5 — A Mine Ventilation And Cooling Network Simulation Tool, W. M. Marx
Environ 2.5 — A Mine Ventilation And Cooling Network Simulation Tool, W. M. Marx
U.S. Mine Ventilation Symposium
As mining operations progress, ore reserves are depleted and alternative are almost invariably found at increasing depth and a host of attendant difficulties in this regard face· the mine operator. Most significant among these is the control of the increasingly hostile environment encountered at depth in terms of both ground behaviour and the increasing hot environment. To enable the practical and economical design of mine ventilation and cooling systems, ventilation practitioners need effective and efficient tools to perform their duty. One such tool is the Environ 2.5, an interactive network simulation program that allows for the simultaneous simulation of airflow …
Radiological Modelling Software For Underground Uranium Mines, Brian Bjorndal, Reza Moridi
Radiological Modelling Software For Underground Uranium Mines, Brian Bjorndal, Reza Moridi
U.S. Mine Ventilation Symposium
The Canadian Institute for Radiation Safety (CAIRS) has been developed computer simulation software for modelling radiological parameters in underground uranium mines. The computer program, called 3d RAD, allows radiation protection professionals and mine ventilation engineers to quickly simulate radon and radon progeny activity concentrations and potential alpha energy concentrations in complex mine networks. The simulation component of 3d RAD, called RSOL VER, is an adaptation of an existing modelling program called VENTRAD, originally developed at Queen's University, Ontario. Based on user defined radiation source terms and network physical properties, radiological parameters in the network are calculated iteratively by solving Bateman's …
Ventilation Network Optimization For Deep Mines, Ventzislav Bojilov, Mitko Hadjiev, Georgi Shoushoulov
Ventilation Network Optimization For Deep Mines, Ventzislav Bojilov, Mitko Hadjiev, Georgi Shoushoulov
U.S. Mine Ventilation Symposium
The development of underground mines in Bulgaria has reached depth limit. The conventional approach for engineering the mine ventilation is unsatisfactory under the existing level of concentration and intensification of mining work under the already complicated mining and geological conditions. This necessitates the optimization of ventilation networks for achieving the required efficiency and reliability. Direct measurements in mines has created an adequate numerical mine ventilation model. This model can optimize and forecast the future development of the mine ventilation system with the help of computer software. By means of the prepared nomograms the individual parameters of the ventilating flow are …
Genetic Algorithm Optimization Of A Large U.K. Coal Mine Ventilation Network, Zhi-Yuan Yang, I. S. Lowndes, B. Denby
Genetic Algorithm Optimization Of A Large U.K. Coal Mine Ventilation Network, Zhi-Yuan Yang, I. S. Lowndes, B. Denby
U.S. Mine Ventilation Symposium
This paper reports on results of an application of a genetic algorithm to the optimisation of a large UK Coal Mine Ventilation Network. The genetic algorithm technique has been developed into a computer program for minimising the total network operating fan power costs. The application of booster fans may become an attractive alternative for ventilation engineers to provide an adequate supply of fresh air around the working areas in some deep and/or extensive mines. The objective of this research is to minimize the total power consumption of a ventilation system by determining the optimum combinations of (1) main fan and …
Msha Approval Process, David C. Chirdon
Msha Approval Process, David C. Chirdon
U.S. Mine Ventilation Symposium
The hazardous nature of the underground mining environment necessitates the use of equipment and mining products designed to ensure safe usage in this hostile environment. Title 30, code of federal regulations (30 CFR) includes requirements that all equipment and products intended for use in potentially gassy areas of underground mines be approved by the mine safety and health administration (MSHA). Design and performance requirements for many of the products intended for use in the underground environment are also part of 30 CFR. This paper describes the processes available to potential applicants for obtaining MSHA approval. Emphasis is placed on ventilation-related …
Ventilation Optimization — Balancing The Need For More Power Against Environmental Concerns, Stephen G. Hardcastle, R. D. Lamond, D. T. Willoughby
Ventilation Optimization — Balancing The Need For More Power Against Environmental Concerns, Stephen G. Hardcastle, R. D. Lamond, D. T. Willoughby
U.S. Mine Ventilation Symposium
This paper shows how the Nanisivik mine was able to improve the underground working environment, decrease operational costs, and reduce its impact on the environment through optimizing their ventilation system. Through re-organizing their ventilation system, the overall flow through the mine increased by at least 20%, and local flows increased by over 100%. This change also resulted in a 45% reduction of fan motor power. And as a consequence of reduced power demands the mine has decreased its Green-house gas (GHG) emissions. Currently, ventilation is typically responsible for 40% of a Canadian mine's underground electrical consumption. This could dramatically change …
An Integrated Strategy For Emergency Egress From An Underground Metal Mine, Rick Brake
An Integrated Strategy For Emergency Egress From An Underground Metal Mine, Rick Brake
U.S. Mine Ventilation Symposium
The fact that major fires are rare events in underground metal mines means there is often little on-site experience in dealing with these situations. Elaborate strategies that rely on a high degree of training at all levels to be effective are likely to fail, especially with the trend in Australia towards smaller mines and "fly in-fly out" operations. A robust strategy is required. The key items in such a strategy are: early detection and warning of personnel, personal belt-worn oxygen-generating self-rescuers, high integrity escape routes and self-contained refuge stations, simple procedures, reliable personnel ''tagging" systems and sufficient, trained, search and …
Mine Safety In Chinese Coal Mines: Today And Tomorrow, Xintan Chang, Yunxiu Sai
Mine Safety In Chinese Coal Mines: Today And Tomorrow, Xintan Chang, Yunxiu Sai
U.S. Mine Ventilation Symposium
As a result of governmental agency restructuring, China's coal industry has been going through evolutionary changes as well in recent years. This paper discusses the various structural changes within the former Ministry of Coal Industry (MOCI) that occurred recently and its impact on coal production, health and safety regulation enforcement, safety training, and higher education.