Matte weather

In the mining industry, dull weather is the name given to the air that is spoiled and used up with too little oxygen. Dull weather contains admixtures of non-toxic gases. If the proportions of these gases such as methane , hydrogen , carbon dioxide and nitrogen are too high, the air can no longer be breathed by humans. In Silesian mining, the dull weather was called stifling weather or ordinary bad weather. In Scottish mining they called such weather Chokedamp (nitrogen steam).

Emergence

Dull weather is caused by the consumption of the oxygen contained in the breath. Some of the oxygen is consumed by the miners' breathing. During oxidation processes with types of rock containing iron oxide, part of the oxygen is chemically bound. Some of the oxygen is consumed by combustion processes, such as the earlier operation of the burning miner's lamps . Some of the oxygen is consumed by putrefaction processes in the pit wood. In hard coal mines, some of the oxygen is consumed by the oxidation of the coal and the pyrites it contains . Carbon dioxide is formed through breathing and the decomposition processes. In pits that are badly or not at all weathered , dull weather can accumulate more intensely. Due to the greater density of carbon dioxide, these gases first collect in the lower area of ​​a mine. If ventilation is not used for a longer period of time, the entire mine will gradually fill up with these gases. In potash mining , the accumulation of carbon dioxide in the rock can lead to dangerous CO ₂ outbreaks. However , if the special ventilation fails in certain mine structures, dull weather can also result from creeping weather currents from insulated mine structures.

Effects

Due to the strong reduction in oxygen, open mine lamps first burn dull and dark, later the light goes out completely. With an oxygen content of 16 percent, a person can still live in these types of weather. If the oxygen content is lower, the air can no longer be breathed by humans. If a person stays in this oxygen-poor environment for a long time, suffocation occurs. This manifests itself initially through accelerated breathing, tightness in the chest, anxiety, sweats and even death. The formation of dull weather can also lead to fatal accidents in modern mining. In 1988, for example, a weatherman had a fatal accident while traveling on a non- penetrable stretch . In 1999, a shaft hammer was killed while driving on a blind shaft head that was enriched with dull weather .

prevention

The best prevention is good and sufficient ventilation, so that dull weather cannot collect in the mine workings in the first place. After a business interruption, miners may only re-enter the mine workings, in which dull weather cannot be excluded, after a weather measurement . In areas with special ventilation, the required minimum amount of weather must be constantly monitored by weather measuring devices. When certain limit values ​​are reached, there must be an optical and acoustic warning signal in the security room. When driving into shaft sumps , depending on the local situation, it is often necessary to carry special handheld carbon dioxide meters and oxygen meters in order to check the weather in these mine structures. In potash mines, miners carry special breathing apparatus with them in order to be able to escape from the affected area in the event of a carbon dioxide outbreak.

See also

• Bad weather

Individual evidence

1. ↑ ^{a b} Explanatory dictionary of the technical terms and foreign words that occur in the mining industry, in metallurgy and in salt works, and technical art expressions that occur in salt works . Falkenberg'schen Buchhandlung publishing house, Burgsteinfurt 1869.
2. ^ ^{A b c} Walter Bischoff , Heinz Bramann, Westfälische Berggewerkschaftskasse Bochum: The small mining dictionary . 7th edition, Verlag Glückauf GmbH, Essen 1988, ISBN 3-7739-0501-7 .
3. ^ Carl Hellmut Fritzsche: Textbook of mining science. First volume, 10th edition, Springer Verlag, Berlin / Göttingen / Heidelberg 1961.
4. ^ Carl Johann Bernhard Karsten: Archives for Mineralogy, Geognosy, Mining and Metallurgy . First volume, printed and published by G. Reimer, Berlin 1829.
5. ↑ ^{a b c} Carl von Schauroth: The pit weather . at JCB Mohr, Heidelberg 1840.
6. ↑ Moritz Ferdinand Gätzschmann: Complete guide to the art of mining. Third part; The mining theory, published by JG Engelhardt, Freiberg 1846.
7. ^ Heinrich Veith: German mountain dictionary with evidence . Published by Wilhelm Gottlieb Korn, Breslau 1871.
8. ↑ ^{a b c} Landesoberbergamt NRW: Fatal accident due to dull weather in a blind shaft head with special weather (accessed on May 16, 2012).
9. ^ Gustav Köhler: Textbook of mining science. 6th improved edition, published by Wilhelm Engelmann, Leipzig 1903.
10. ^ Landesoberbergamt NRW: Fatal accident due to dull weather in a blind shaft head with special weather (accessed on May 16, 2012).
11. ↑ Albert Serlo: Guide to mining science. Second volume, 4th improved edition, published by Julius Springer, Berlin 1884.
12. ↑ General Mountain Police Ordinance Online ( Memento from June 7, 2012 in the Internet Archive ) (PDF; 233 kB).
13. ↑ Dräger Review 384: Protection for the City Underground . February 2010 Online  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (accessed on May 16, 2012; PDF; 3.2 MB).