All the coal had been removed and the resulting space was termed a "goaf". When the props were withdrawn the roof was allowed to fall into the goaf.
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To avoid spontaneous combustion of coal in the goaf area, gases may be allowed to build up behind seals so as to exclude oxygen from the sealed goaf area. Where a goaf may contain an explosive mixture of methane and oxygen, nitrogen injection/inertisation may be used to exclude oxygen or push the explosive mixture deep into the goaf where there are no probable ignition sources. Seals are required to be monitored each shift by a certified mine supervisor for damage and leaks of harmful gases.
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He also worked in London for the Soviet trading mission and later Intourist. In 1934, his novel Goaf was released in English.
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Gannister :Gannister is siliceus fireclay which can be used to make firebricks. Garland :A garland was a water channel or gutter in the lining of a mine shaft. Gate :A gate is a tunnel serving the coal face, the maingate is where fresh air enters and the tailgate is where spent air exits. Goaf, gove or gob :The goaf, gove, gob, shut or waste is the void from which all the coal in a seam has been extracted and where the roof is allowed to collapse in a controlled manner.
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The Government Opium and Alkaloid Factories (GOAF) is an Indian government- owned organisation. Its headquarter is located in New Delhi. There are two factories under this organisation - Government Opium and Alkaloid Works, Ghazipur (U.P.) and Government Opium and Alkaloid Works, Neemuch (M.P.).
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Windblast is common in longwall coal mines, especially those whose roof strata are competent, and do not cave immediately behind the roof supports as the face advances. This results in the tendency for a large void to be created behind the roof supports in the goaf (or gob) which collapses when the overlying cantilevered strata can no longer support its own weight. When the collapse occurs, the air or gas occupying the void is displaced by rock, resulting in a pressure wave and windblast that propagates along the roadways (tunnels) of the mine. This may be followed by a "suck back" as the air pressure is equalised with the low pressure created higher up in the goaf.
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Pit props were progressively removed and the roof was allowed to subside into the goaf a short distance behind the working face. Woolley was removing pit props when the fracturing roof released firedamp. The flame in Woolley's Davy lamp turned blue indicating explosive gas. Instead of reporting it, work continued.
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At Easington in 1951 blunt picks hit a patch of pyrites and generated sparks. This time the firedamp leaking from the void above the goaf was ignited. The resulting explosion travelled down the south headings to the west roads. Such an explosion in a confined space causes a blast of air which can raise up any dust lying around.
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Eventually the whole district consisted of a grid pattern of passageways around stoops. The final stage in extraction was "stooping". The furthermost roof was supported by pit props and the stoops removed. Once a complete row of stoops had gone the props were removed from the furthest part which would collapse into the space ("goaf" or "gove") behind.
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In 1926, Heslop's first novel Goaf was published, but it was in a Russian translation as Pod vlastu uglya and did not appear in England until 1934. This novel, about mining in northern England, "sold half a million copies in Russia and made Heslop's name there", though he was only able to transfer a small part of his royalties to England.
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The Government Opium and Alkaloid Factories (GOAF) is an Indian government-owned organisation. Its headquarter is located in New Delhi. Each year the Central Government notifies the selected tracts where such cultivation will be permitted, and the general conditions for eligibility of the licence. The essential condition for issue of licence is, fulfillment of minimum qualifying yield (MQY) criterion, specified in number of kilograms per hectare.
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The commission concluded that no normal testing would have revealed the gas accumulation in the roof of the goaf. Rather than holding any individual official of the Mount Kembla Company responsible, the Commission stated that only the substitution of safety lamps for flame lights could have saved the lives of the 96 victims. However, flame lights continued to be used well into the 1940s.
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The tailgate road is formed behind the coal face by removing the stone above coal height to form a roadway that is high enough to travel in. The end of the block that includes the longwall equipment is called the face. The other end of the block is usually one of the main travel roads of the mine. The cavity behind the longwall is called the goaf, goff or gob.
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The coroner's inquest was not heard until 23 September 1886 so that John Woolley, who had survived the explosion, could give evidence. The coalface where the explosion occurred was being worked on the retreating principle. Headings had been driven into the coal and a working face established between them. As the coal was worked back along the headings, waste material accumulated in the goaf or gob behind it.
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It was allowed to gradually subside, crushing the pack walls down. To prevent subsidence beneath Agecroft Hall, a pillar of coal about square had been left some beyond the limit of the 1885 workings. In the goaf the roof broke away from the Trencherbone rock resulting in voids forming above the low grade coal. The tunnel to the five-quarters mine and on to the Agecroft Colliery was not in regular use.
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The cuts are made towards the roads, thus the face retreats from the where it started back towards the start of the headings. Behind the cut is a void (known as "goaf") into which spoil was placed and normally the roof is allowed to collapse upon this spoil as props are withdrawn. In the case of the 3rd south workings this collapse did not occur properly and a void developed above the spoil.
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As this wall retreated the roof was propped and the furthermost props removed, allowing the overburden to collapse into the goaf. With longwall the same fracturing and gas release that stooping could cause was always present. The ell coal was mainly worked by stoop and room, with longwall in the southern part only. The main was exclusively worked by longwall and the splint (apart from a trial section) worked by stoop and room.
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100 In 1934, the original English version of Heslop's novel Goaf was published, as well as The Crime of Peter Ropner, which is an "attempt at a crime novel from a left-wing perspective".H. Gustav Klaus, The Literature of Labour, p.102. Crime novelist Dorothy L. Sayers reviewed it, and while disliking much about it, found that it had "a crude and sordid power".H. Gustav Klaus, The Literature of Labour, pp.102–3.
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Previous depillaring had been done by caving method but later working goaf pillar method was being followed in one district. Another depillaring district was being worked with hydraulic sand stowing. One development section in the east of main dip section was being worked with SDL. 7\. Bejdih I UG mine, with normative annual production capacity of 0.04 mt and peak annual production capacity of 0.10 mt, had an expected life of over 20 years.
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A roof fall in the 4th Right goaf drove out a considerable amount of a fire-damp/air mixture. The Mixture passed along the 4th Right road crossing the No. 1 Right traveling road and bursting through the canvas doors into No 1 Right haulage road. As the mixture travelled it raised coal dust which was carried with it. The mixture started to travel outbye before being stopped by the ventilation air current and forced back inbye.
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Heslop's literary career began in 1926 with the Russian version of Goaf and then, starting with The Gate of a Strange Field, Heslop published five novels in England between 1929 and 1946, while his autobiography, Out of the Old Earth, was published posthumously. Harold Heslops's first novel published in England, The Gate of a Strange Field is about the General Strike of 1926, which he had witnessed in London.John Lucas, The Radical Twenties. Rutgers University Press 1999. (pp. 237–38).
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Here it is loaded on to a network of conveyor belts for transport to the surface. At the main gate the coal is usually reduced in size in a crusher, and loaded on to the first conveyor belt by the beam stage loader (BSL). As the shearer removes the coal, the AFC is snaked over behind the shearer and the powered roof supports move forward into the newly created cavity. As mining progresses and the entire longwall progresses through the seam, the goaf increases.
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The area above the goaf was inadequately ventilated and acted as a reservoir for firedamp. The origin of the firedamp is debatable: either the fractured roof allowed a sudden outburst from the seams above, or else the firedamp was gradually emitted from the waste into the void. Roberts discusses these possibilities in the report and comes down in favour of the latter. All collieries are susceptible to the build up of coal dust, not just at the face but along the roadways and conveyors.
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Harold Heslop (1 October 1898 – 10 November 1983) was an English author, left- wing political activist, and coalminer, from near Bishop Auckland, County Durham. Heslop's first novel Goaf was published in 1926, but it was in a Russian translation as Pod vlastu uglya and did not appear in England until 1934. In 1929, he also published his first novel in England, The Gate of a Strange Field, about the 1926 United Kingdom general strike. His last novel, The Earth Beneath, was published in 1946.
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After a further three fatalities in the early 1880s following roof falls, 53-year-old George Mosby was crushed to death by a stone on 6 September 1886. Fellow miner, Samuel Marriott heard his cry, and found him in the goaf, his legs crushed under the stone. Marriott and John Sutton, managed to free him after 15 minutes and put him in a corf, but Mosby died 15 minutes later. John Gerrard, Inspector of Mines attended the coroner's inquest.Major Thomas Taylor, Coroner’s Report, Wednesday 8 September 1886 Samuel Marriott would also survive the 1896 Disaster, as would George Mosby's son, Lot.
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South of the shafts the coal had largely been worked out back to the supporting pillar for about of the distance, that to the south was being actively worked at the time of the explosion. Headings were labelled numbers 1 and 2 east and west in the worked section, number 3 east and west and number 4 west in the southern extremity. The large areas to the east and the west of the central roads formed a large area known as the goaf. This space (up to across) was in part supported by pack walls and partially filled with waste.
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Typically, intake (fresh) air travels up the main gate, across the face, and then down the tail gate, known as 'U' type ventilation. Once past the face the air is no longer fresh air, but return air carrying away coal dust and mine gases such as methane, carbon dioxide, depending on the geology of the coal. Return air is extracted by ventilation fans mounted on the surface. Other ventilation methods can be used where intake air also passes the main gate and into a bleeder or back return road reducing gas emissions from the goaf on to the face, or intake air travels up the tail gate and across the face in the same direction as the face chain in a homotropal system.
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The commission came to a different verdict from the coroner's jury. In the first place they queried the meaning of "accelerated by a series of coal-dust explosions" pointing out that the coal-dust explosions were part of the initial blast and not a factor coming into play some time later. The Commission then disagreed over the seat of the explosion, placing it at the junction of the 4th Right road and the No. 1 Haulage road, whereas the Coroner's jury had placed it at number one main level back headings. Once the commission had decided that the likely cause of the explosion was the expulsion of fire-damp from the 4th Right goaf they considered whether blame could or should be attached to any person or persons.
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The day following the explosion the coroner at Wollongong opened an inquiry into the cause of death of the first of the miners brought out. Over the period from 1 August to 12 September 1902 the inquest sat on 22 days hearing evidence from 28 witnesses and visiting the mine. The Jury returned a verdict that the Meurant brothers and William Nelson "came to their death … from carbon monoxide poisoning produced by an explosion of fire-damp ignited by the naked lights in use in the mine, and accelerated by a series of coal-dust explosions starting at a point in or about the number one main level back headings, and extending in a westerly direction to the small goaf, marked 11 perches [] on the mine plan." A royal commission concerning the disaster was appointed on 6 November 1902 and held hearings in March, April and May 1903.
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