2 edition of Quantitating respirable dust levels generated during longwall mining operations found in the catalog.
Quantitating respirable dust levels generated during longwall mining operations
R. Lindsay Mundell
by Dept. of the Interior, Mining Enforcement and Safety Administration, Technical Support Center in Pittsburgh, Pa
Written in English
Bibliography: p. 27
|Statement||by R. Lindsay Mundell and Charles D. Taylor ; Technical Support Center, Pittsburgh, Pa|
|Series||MESA informational report IR ; 1061|
|Contributions||Taylor, Charles D. 1946-, United States. Mining Enforcement and Safety Administration. Pittsburgh Technical Support Center|
|The Physical Object|
|Pagination||, 27 p. :|
|Number of Pages||27|
Table 1 shows the mean dust concentration levels of five major mining regions. Heading faces were found to be the dustiest units producing a mean dust level of mg/m3 and a range of – mg/m3. Longwall faces are the next dusty units of the underground coal mining producing a mean dust level of mg/m3 and aFile Size: KB. The quartz content of the respirable dust was highest for the underground maintenance team (%), followed by the development team (%) and the mining team (%). In development the exposure to respirable dust and quartz was higher for drilling (GM and mg m −3, respectively) than for blasting ( and mg m −3 Cited by:
A Critical evaluation of dust sampling methodologies in Longwall Mining in Australia and the USA Brian Plush University of Wollongong The current testing regime in Australia provides the mine tested with a single figure for respirable dust exposure levels for five samples taken over a minimum of four hours during a production shift. GDKA INCLINE Two longwall sets were introduced with 4xT/4xT supports during , followed by 3rd Longwall unit with 4xT supports during First time longwall was introduced in No.1 Seam of Ramagundam.
A modern longwall is a long term commitment and flexibility is desirable because conditions may change greatly during the life of the equipment (financial conditions may vary and machinery developments may change constraints even if all mining conditions are well known in advance). new respirable dust concentration standards. “Representative samples” are deﬁned thus: Respirable dust samples that reﬂect typical dust concentration levels and normal mining activity in the active workings during which the amount of material produced is equivalent to a normal production shift
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Get this from a library. Quantitating respirable dust levels generated during longwall mining operations. [R Lindsay Mundell; Charles D Taylor; United States. Mining Enforcement and Safety Administration.
Pittsburgh Technical Support Center.]. In addition, MSHA inspector sampling results from show that longwall face workers were exposed to elevated levels of respirable silica dust. For MSHA occupation codes (tail-side shearer operator) and (jack setter) that were on reduced dust standards due to silica levels above 5%, 31% and 21% of the samples, respectively.
generate significantly more dust. Previous NIOSH research has shown that, on average, respirable dust levels generated by the shearer accounts for 50% of the airborne dust generated during longwall mining.
Ventilating air and water are primary controls being used in an effort to reduce longwall dust levels. Longwall operators are applying. Controlling Respirable Dust on Longwall Mining Operations.
– Direct or contributing cause of death underground Controlling Respirable Dust on Longwall Mining Operations Topics of Discussion •Dust levels as high as 20 –30 mg/m3 for a short durationFile Size: 4MB.
Dust on Longwall Mining Operations Statistics and Quantifying Dust Levels Minimize the quantity of respirable dust generated Face Ventilation – Principal method of controlling respirable dust on longwall faces 80 % > ft/min 30 % > ft/min, as high. Quantitating respirable-dust levels generated during longwall-mining operations Technical Report Mundell, R.L.
; Taylor, C.D. During the past 10 years use of longwall methods to mine coal in the United States has steadily increased. longwall mining ha s only recently become important in the industry, its share of total underground coal production having grown from less than 6% before to about 55% in Protecting against airborne dust exposure in coal mines In coal mining, both coal dust and respirable crystalline Open cut workers are possibly at risk during drilling and shot firing operations in the stone overburden if not protected by proper procedures or cabin Size: KB.
The most recently adopted method is the longwall face. The longwall method permits much higher productivity, although it often incurs much higher dust levels. In longwall mining, a machine removes a strip of coal from the coal-face, the roof being supported by jacks.
As the face moves forward, the mined-out area is left to collapse. Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically – m (2 ft 0 in–3 ft 3 in) thick).
The longwall panel (the block of coal that is being mined) is typically 3–4 km (– mi) long and – m (–1, ft) wide. Substantial dust can be generated during drilling operations, particularly if undertaken in dry conditions. The generation of dust needs to minimised as much as practicable.
Control measures include: fitting drills with a water injection or dust extraction system (or both). "These results show that the new dust rule is working, and miners should be breathing cleaner air at coal mines," said Joseph A. Main, assistant secretary of labor for mine safety and health."Despite concerns from some in the mining industry, most of the valid samples collected have met compliance levels.
LONGWALL MINING Overview. In the method of secondary extraction known as longwall mining a relatively long mining face (typically in the range to m but may be longer) is created by driving a roadway at right angles between two roadways that form the sides of the longwall block, with one rib of this new roadway forming the longwall face.
Coal Operators’ Conference The AusIMM Illawarra Branch February RESPIRABLE DUST RESULTS FROM NSW LONGWALL MINES Ken Cram 1 ABSTRACT: An outline of airborne dust sampling methodology, instrumentation and exposure standards in the New South Wales coalmining industry are presented combined with the results of dust monitoring of the mining.
The maximum concentration of dust types including respirable dust, quartz bearing dust and asbestos dust can be obtained from the WORKPLACE EXPOSURE STANDARDS FOR AIRBORNE CONTAMINANTS Dust can be generated during different stages of operations and therefore workplaces may need to determine personal exposure and what precautions may be.
During the continuous mining process, the ratio of total airborne float coal dust to respirable dust ranged from to The ratios measured on the longwall face were between and The total airborne float coal dust to respirable dust ratio observed during belt Cited by: 1.
Recent increases in coal production from the financial incentive of economic growth lead to higher respirable coal and quartz dust levels, often associated with mechanization of longwall coal mining.
The respirable dust limit formula suggests the first explanation: a mine with a high silica % in the dust is required to keep the dust concentration low under the reduced standard. Additional explanations are also proposed: the variability of the % of silica in the dust, the selective efficiency of control technologies, and different transport Cited by: 5.
(c) When the respirable dust standard is changed in accordance with §the new applicable standard shall become effective 7 calendar days after the date of notification of the change by MSHA. (d) If a normal production shift is not achieved, the DO or ODO sample for that shift may be voided by MSHA.
The standard limiting respirable dust in the mine atmosphere to mg/m 3 was retained in the Mine Act, which also required that “each operator shall continuously maintain the average concentration of respirable dust in the mine atmosphere during each shift to which each miner in the active workings of such mine is exposed at or below.
Longwall mining is the dominant form of underground coal mining methods in Australia. As production. increases there is also a need for increased face ventilation rate for gas dilution and dust mitigation.
The. behaviour of gas emission and respirable dust in a longwall face is a complex process because of the nature. of longwall operations.Respirable dust concentration is lower than MAC during longwall shearer cutting when using the air-and-water spraying system. Dust concentration at the operator’s workstation, when mining direction is against the flow of fresh air is given in Fig by: Longwall Mining Longwall mining has had the biggest impact on U.S.
underground coal operations over the past 20 years. Although the concept originated in Europe, modern longwall mining in the U.S. began in and as equipment improved, became more widely used in the 70's.