Coal mining underground hazards

Carbon monoxide is highly toxic because it has a higher affinity for hemoglobin than does oxygen. CO sensors are therefore of utmost importance for combustion control, fire-alarm systems, and detection of hazardous concentrations of the gas in private and industrial facilities such as tunnels, coal mines, and underground garages. The sensors in current use, in which CO is anodically oxidized or adsorbed onto coated piezoelectrodes, are relatively nonspecific, since H2S, N2O, and NO2 interfere. 

In general, radium in rock does not pose a health risk, but there are situations where radium is found in unusual abundance, and care must be taken with human exposure. Oil fields, coal mines, and phosphate mines generate hazardously high concentrations of radium as uranium and thorium deposits are disturbed underground. In Poland, for example, radium-containing water that was discharged from coal mines has been... 

Theodore Barry and Associates, Inc. (1971). Industrial engineering study of hazards associated with underground coal mine production. Los Angles, California Author, NTIS No. PB 207 226. 

The spot investigation about the relationship between K, and W of No.3 coal seam had been down at Daning coal mine for verifying the reliability and correctness of the above research results,. Because the gas occurrence is inhomogeneous and there are inevitable errors when measuring gas parameters underground, make the max gas parameters as the true value for objectively reflecting the coal and gas outburst hazard furthest. The results were drawn into K,-W curves in Fig. 3. 

The related theory about extenics is founded by the Chinese scholars Cai wen to solve the problem of subjective and objective contradictions in 1983 (Cai, 1983), it bases on the matter-element theory and extension set theory and does research on the influence degree of the described problems about quantity and quality , so as to completely know the system features (Guo et al., 2009). Due to the complexity production conditions of underground working face, there are a variety of factors that affect gas emission, how to quickly and accurately judge the reasons that why the gas emission is abnormal is an important task of gas early-warning, the extension theory can calculate the abnormal gas emission level by using the normalized correlation function. Under the condition of correct identification of gas hazard in coal mine. 

Coal mining has always been, and remains, a dangerous occupation. Mine atmospheres are hazardous in terms of the health and safety of miners and, although technological advancements and legislation have led to improvement in the environmental and safety aspects in mines, pollutants are still produced at significant levels from coal excavation in both surface and underground mines. 

I focus in what follows on the approved standard for a particular hazard, spontaneous combustion, since this phenomenon has been responsible for three major explosions in underground coal mines in Queensland in a space of 20 years. A total of 41 men were killed in these explosions. 

Coal workers pneumoconiosis is also a concern at surface coal mines and preparation plants, but not to the extent as in underground mines for high-risk occupations. Dust control measures for surface mines (primarily for dust generated from drilling, hauling, and crushing) are different from the ones implemented in underground mines, and these will be covered in the section on control of hazards. 

In underground coal mines, tens of thousands of intersections are driven each year. Intersections create diagonal spans of 8 to 12 m (25 to 40 ft), well over the normal width of an entry. The hazards of wide spans can be increased when pillar corners are rounded for machine travel (turnouts), or when... 

This chapter has presented an overview of the most significant ground control hazards facing todays mineworkers. Underground miners, particularly in coal mines, are at the greatest risk from ground falls. The six highwall and slope fatalities that occurred in the first half of 1999 show that surface miners are at risk as well. 

The hazards associated with continuous haulage systems underground have been described by el-Bassioni (1996) in an article that documents fatalities, injuries, safety issues, and safe work procedures. Continuous haulage systems, also known as bridge conveyors, are used with continuous miners. Concerns unique to continuous haulage systems include lack of communication between a miner and haulage operators, the lack of space around the systems, and Hmited visibiUty. Figure 26.6 illustrates an actual fatality in a coal mine. The operator was killed when his shuttle car bumped into the rib, and he was crushed between the rib and the car. 

In fact, coal-bed methane is an explosive hazard in underground mining operations and for safety reasons has traditionally been vented with mines fresh air circulation. Since the 1970s, methane captured from underground mining has increasingly been used to supplement local gas supplies (WEA, 2000). 

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